*LECTURE EXAM 4* - MICRO 2420

What is a toxoid?

Inactivated toxin used in a vaccine

Toxoids

Inactivated toxins

Transmission of pathogen by doorknob or stethoscope is an example of what kind of transmission?

Indirect contact

Ways antibacterial drugs act against bacterial pathogens EXCEPT

Inhibitiion of endospore formation

What are DNA vaccines?

Injected naked DNA antigens which are carried to the red bone marrow and become part of the immune response

Where does digestion occur?

Inside phagolysosome

Infection

Invasion or colonization of the body by pathogens

IgE

Involved in allergy and anti-parasitic activity

Biological transmission of pathogens by vectors differs from mechanical transmission in that biological transmission

Involves reproduction of a pathogen in an arthropod vector prior to transmission.

What is inflammation?

Is a component of the second line of defense. It provides innate immunity by destroying the injurious agent and removing it if possible and also by limiting the effects on the body by confining the injurious agent. Another component of the second line of defense, damage to the body's tissues

How does a vaccine work?

It activates the body's primary immune response which then creates a secondary immune response

epidemic?

"out break" acquired by man people in a short period of time.

What is an antigen-antibody complex?

It forms when antibodies bind to antigens

What is an anaphylactic reaction?

It is a life threatening immediate allergic reaction that causes respiratory distress, severe bronchospasm, and cardiovascular collapse. Treat with epinephrine, bronchodilators, and antihistamines.

What is AIDS?

(acquired immune deficiency syndrome) : AIDS is not a single disease, but a syndrome-group of signs, symptoms, & diseases associated with common pathology. AIDS is characterized by the presence of several rare or opportunistic infections along with infection by human immunodeficiency virus (HIV) or as a severe decrease in CD4+ cells (<200/ul of blood) & a positive test showing the presence of HIV. A wide variety of opportunistic infections & rare cancers occur in AIDS patients. AIDS is the end stage of HIV infection. At this point, the virus has attacked and weakened a person's immune system

What are the production of Exoenzymes?

* Coagulase * Kinase * Hyaluronidase * Collagenase * IGA proteases

How does a microorganism adhere to the host cells?

* Mechanism of Adhesion * Between the adhesions of bacteria and receptor proteins on the surface of host cells

What are dendritic cells? (Experienced Paramedics)

*Agranulocyte* >Long extensions like nerve cells >Found in skin, mucous membrane, thymus, lymph nodes >Phagocytic >Initiate adaptive immunity (Experienced Paramedics because they can already take care of situations when they arrive at the scene)

What are monocytes? (Brand new Paramedics)

*Agranulocyte* >Phagocytosis is enabled once they leave the blood and enter tissue -> mature into *Macrophages* (Brand new Paramedics because they are immature but after they roll out, they're ready for action)

What are NK (natural killer) cells?

*Agranulocyte* (Lymphocyte) >Destroy target cells by cytolysis and apoptosis

What is an A-B toxin?

*Exotoxin* Consists of two-parts: The A subunit is the toxic (active/enzyme) portion and the B (binding) subunit binds to a specific surface molecule on cells.

What are eosinophils? (HAZMAT team)

*Granulocyte* >Lead the bodys counterattack against parasitic worms, >Lessen the severity of allergies by phagocytizing immune complexes. (Not often phagocytic) (HAZMAT because they are trained to answer only to very specialized calls)

What are basophils? (Switchboard Operator)

*Granulocyte* >Releases the histamine chemical to intensify the inflammatory response (so other white blood cells are attracted to the inflamed area.) (S/O because they direct other cells to the scene)

What are neutrophils? (Squad Car)

*Granulocytes* >Highly motile >Phagocytic >First to respond to infected tissues (Squad Car because they're the first on the scene)

Cell wall components

*M protein- resist phagocytosis/ Streptococcus pyogenes *Opa protein- allows attachment to the host cells/ Neisseria gonorrhoeae *Waxy lipid (Mycolic acid)- resists digestion/ Mycobacterium tuberculosis

What is the role of the following in the primary response (and in colonial selection of antibody-producing B cells)?

*MHC class II- round on the surface of antigens presenting cells (apc). During the colonial selection of antibody producing B-cells antigen fragments are typically displayed on these MHC class II molecules * APC- * Cytokines- signaling molecules * T helper cell- recognizes the antigen presented by the B cell (APC) and releases cytokines to activate the B cell to produce antibodies against the antigens.

What is IgG?

*Most common antibody* Found: Blood, lymph, intestine Function: Enhance phagocytosis, trigger compliment, and neutralize toxins

Which of the white blood cells are phagocytic? Which white blood cells become the macrophages? How do phagocytes attach to pathogens?

- All white blood cells are phagocytic - Neutrophils, eosinophils, and monocytes migrate into tissues and turn into macrophages. - Phagocytes attach to the pathogens thru adherence which is the attachment of the phagocytes plasma membrane to the surface of the microorganism.

Type 1 (anaphylactic) Preventing Anaphylaxic Reactions

- Antigens are inoculated beneath the epidermis to test for a rapid inflammatory reaction (wheal) - Desensitization: increasing doses of antigen injected beneath the skin. Then the body produces IgG, which act as blocking antibodies to intercept and neutralize antigens

Mechanism of Type 1 (Anaphylactic)

- Antigens combine with IgE antibodies - IgE attaches to mast cells and basophils - Mast cells and basophils undergo degranulation, which releases mediators a. Histamine- increases the permeability of blood capillaries b. Leukotrienes-cause prolonged contraction of smooth muscles c. Prostaglandins- affect smooth muscle and increase mucus secretion

How did our body acquire the microbiota?

- At birth-passage through the birth canal - From the environment

What are the symptoms associated with superantigens?

- Fever - Nausea - Vomiting - Diarrhea - Tremors - Shock

Review over different types of white blood cells, Granulocytes, and agranulocytes

- Granulocytes contain large granules in their cytoplasm. Includes neutrophils (stain pale lilac and also known as polymorphism, highly phagocytic and motile, initial stages of infection) - Basophils (stain blue-purple with basic dye methylene blue, release histamine) - Eosinophils (stain red or orange with acidic dye eosin, somewhat phagocytic and have the ability to leave the blood, they kill certain parasites such as helminths; can also attach to outside surface of parasites and discharge peroxide ions that destroy them. Numbers increase during certain parasitic worm infections and allergy reactions.) - Agranulocytes have granules that cannot be seen, they include Monocytes not actively phagocytic until they leave circulating blood, Exeter tissue, and turn into Macrophages.

Other Antifungal Drugs?

- Griseofulvin - Tolnaftate - pentamidine

What are interferons and what do they do?

- If a cell is infected, it can produce interferon and release it. It is taken up by cells around it to protect them from infection in other cells. WBC can produce interferon can activate macrophages to become more phagocytotic - Used in cancer therapy.

What are mechanisms of action for anti-fungal drugs?

- Inhibition of cell wall synthesis - Injure Plasma Membrane - Inhibition of nucleic acid replication

When are endotoxins like Lipid A released from the bacteria?

- Lipid A portion of LPS (lipopolysaccharides) of gram negative bacteria; released during bacterial multiplication and when gram negative bacteria die - Stimulates macrophages to release cytokines; cause disseminated intravascular coagulation

What are the different portals of entry of pathogens?

- Mucous membranes (respiratory, GI tract, genitourinary) - Skin - Parenteral route- deposited directly into tissues when barriers are penetrated

Agents affecting fungal sterols (plasma membrane)

- Polyenes - Azoles - Allylamines

How does the body benefit from the normal microbiota in terms of disease?

- Protects the body from invading microorganisms through microbial antagonism. - Producing substances harmful to invading microbes. - Affecting pH and available oxygen.

How does vaccination confer adaptive immunity?

- Provokes a primary immune response - Leads to the formation of antibodies and memory cells

What are the 4 signs of inflammation?

- Redness (rubor) - Heat(calor) - Swelling (tumor) - Pain (dolor)

What are the major reservoirs of pathogens, and in what ways diseases are transmitted?

- Reservoirs of infection, the sources of infection; these are needed for the continuous presence of the disease. 1. Human reservoirs 2. Animal reservoirs 3. Non-living reservoirs

What are the 5 portals of exit?

- Respiratory tract - Gastrointestinal tract - Genitourinary tract - Skin - Blood

What are the portals exit of pathogens?

- Respiratory tract- Coughing and sneezing - Gastrointestinal tract ( hi tract)- Feces and salvia - Genitourinary tract- Urine; secretions from the penis and vagine - Skin - Blood- Arthropoda that bite; needles or syringes

Type 1 (Anaphylactic) systemic anaphylaxis (anaphylaxis shock)

- Results when an individual sensitized to an antigen is exposed to it again - May result in circulatory collapse and death - Treated with epinephrine

Nucleic Acid Synthesis Inhibitors

- Rifamycin - Quinolone - Fluoroquinolones

Assembly & Exit inhibitors

- Saquinavir - Boceprevir - Zanamivir - Oseltamivir - peramivir

What are the chemical factors involved in providing innate immunity?

- Sebum- forms a protective film and lowers the pH (3-5) of skin. - Lysozyme- in perspiration, tears, salvia, and urine destroys bacterial cell walls - Low pH (1,2,3,0) of gastric juice- destroys most bacteria and toxins - Low pH(3-5) of vaginal secretions- inhibit microbes

What are the physical factors involved in providing innate immunity?

- Skin- shedding and dryness of skin inhibits microbial growth - Mucous membrane - traps microbes and prevent tracts from drying out - Lacrimal apparatus- tears wash eyes - Salvia- prevent colonization of bacteria on mouth - Ciliary escalator- transport microbes trapped in mucus away from lungs - Ear wax- prevents microbes from entering the ear - Urine- cleans the urethra via flow - Vaginal secretions- move microorganisms out of a vaginal tract Peristalsis, defecation, vomiting, diarrhea

What are the three types of lymphocytes?

- T cells - B cells - Natural killer cells

Type 4: what happens as a result of this hypersensitivity?

- This involves T-cells & macrophages; EX: transplant rejections, antibody-dependent cell mediated toxicity (ADCC), & complement-mediated lysis - Cell-mediated immune responses caused by T-cells, causing sensitization Reexposure to antigen causes memory cells to release destructive cytokines - Allergic contact dermatitis: haptens combine with proteins in the skin, producing an immune response; Allergic response to poison ivy, cosmetics, metals, & latex

Type 1 (anaphylactic) Localized anaphylaxis

- Usually associated with ingested or inhaled antigens - Symptoms depend on the route of entry - Hives, hay fever, and asthma

What are the stages involved in inflammatory process? Know what happens in each stage!

- Vasodilation occurs which is responsible for the redness. Increased permeability is responsible for the edema. - Blood clots form to prevent the spread of the microbe an abscess may occur. - Final stage is tissue repair

Which of these are examples of local infections? Check all those that apply.

- athlete's foot - conjunctivitis - pimples

How are the outcomes of activating the complement system involved in providing innate immunity?

- create a membrane attack system (MAC), cell lysis - Promote attachment of phagocyte (opsonization) - Cause inflammation, bind to mast cells, releasing histamines

In which of the following stages of disease progression does the patient experience no signs or symptoms? Check only those that apply.

- incubation - covalence

One will get sick only when the infecting pathogen undergoes rapid multiplication within the body. The rapid increase of a bacterial pathogen occurs during the ______________ phase of the bacterial growth curve; corresponding to the ______________ period of disease progression or development.

- log - illness

What are the types of cytokines?

- lymphokines - Interleukins - Tumor necrosis factor - Interferons - transforming growth factor

What is the alternative pathway?

-C3 present in the blood combines with factors B, D, and P on microbe surface -C3 splits into C3a and C3b, functioning the same as in the classical pathway

Which of these infectious diseases are both contagious and communicable? Check all those that apply.

-COVID-19 -tuberculosis -gonorrhoea

How are interferons involved in providing innate immunity?

-IFN-a and IFN-B stimulate NK cells, which produce IFN-y. -IFN-y is produced by lymphocytes and induces neutrophils and macrophages to kill bacteria.

How is fever involved in providing innate immunity?

-Interleukin 1 helps step up production of T cells -Intensifies the effects of antiviral interferons -Increases production of transferrins that decrease the iron available to microbes -High temp speeds up the body reaction to repair damage. -High temp slows down growth of same bacteria.

What are inactivated (killed) vaccines?

-Non-living virus is killed with chemicals or heat Ex: Rabies, flu *shot*

Most of the exotoxins produced by toxigenic bacteria come in the form of A-B toxin. The A component does ______________, while the B component does.

-cause the disease by inibiting protein synthesis -allow toxin to bind to target cell

Zoonotic infections are cases in which pathogens spread from nonhuman animals to humans. Which of the following are considered as zoonotic diseases? Check all those that apply:

-malaria -Lyme disease -rabies -tetanus

In which ways one can get healthcare-associated infections or nosocomial infections? Check of all those that apply.

-using unsanitized bed pan -nurse shaking hand with the patient -a doctor not changing gloves in palpating/examining one patient after another

Which of these pathogens can escape from the host immune responses by being able to survive inside the phagocytes? Check all those that apply

.Plasmodium Coxiella burnetti Mycobacterium tuberculosis Rickettsia species

What are the 4 main phases of phagocytosis? Know what happens in each phase!

1 - Chemotaxis and Adherence- the chemical attraction of phagocytes to microorganisms and the actual attachment 2 - Ingestion- pseudopods engulf microorganisms that surround it with a sac called phagosome 3 - Phagosome & lysosome membranes fuse to form a single layer called phagolysosome 4 - After those contents are digested it is brought into the cell by ingestion and is called a residual body. This residual body discharges it's waste outside the cell.

What are the 5 steps to an A-B toxin working? (RAEPS)

1) *R*elease from bacterium 2) B component *A*ttaches (binds) to host cell receptor 3) Host plasma invaginate the toxin via Receptor-mediated *E*ndocytosis 4) Host cell isolates toxin via *p*inocytosis 5) A-B parts *s*eperate A part: Alter cell function B part: Exits Receptor: Returns to Plasma membrane

What are the three types of membrane-disrupting toxins?

1) - Leukocidins* Kill phagocytic WBC's 2) - Hemolysins* Kill RBC's by forming protein channels 3) - Streptolysins* Hemolysins produced by streptococci

What are 5 examples of antibacterial drugs that inhibit protein synthesis?

1) Aminoglycosides 2) Pleuromutilins 3) Tetracyclines 4) Erythromycin 5) Zyvox

What are the physical factors of innate immunity?

1) Barriers to entry 2) Processes that remove microbes from surface of body

What are the 3 classes of autoimmune diseases?

1) Cytotoxic Autoimmune Response 2) Immune complex response 3) cell-mediated response

What are cytotoxic reactions?

1) Hemolytic Transfusion Reactions (when recipient receives ABO-incompatible blood from donor) 2) Thrombocytopenic purpura (platelets combine with drug to form antigen)

What is ingestion?

1) Ingestion of microbe by phagocyte 2) Process of opsonization 3) Formation of phagosome 4) Phagosome + Lysosome = Phagolysosome

What are the 6 ways pathogenic microbes evade phagocytosis?

1) Inhibit Adherence 2) Kill phagocyte 3) Lyse phagocyte 4) Escape phagosome 5) Prevent creation of phagolysosome 6) Survive in phagolysosome

What are the major modes of actions of antibacterial drugs?

1) Inhibition of cell wall synthesis 2) Inhibition of protein synthesis 3) Inhibition of nucleic acid replication 4) Injure Plasma Membrane 5) Inhibition of essential metabolite synthesis

How can you prevent anaphylactic reactions?

1) Introduce small amount of antigen below skin to cause localized reaction 2) *Desensitization* = increasing dosage of antigen beneath skin. This will produce IgG that intercepts and neutralizes antigens

What are the types of vaccines?

1) Live Attenuated 2) Inactivated Killed 3) Subunit 4) Conjugated 5) DNA vaccine

What are 5 classes of antibacterial drugs that inhibit cell wall synthesis?

1) Natural Penicillin 2) Semisynthetic Penicillin 3) Cephalosporins 4) Polypeptide antibiotics 5) Antimycobacterial antibiotics

How does the body benefit from the normal microbiota in terms of disease prevention? Benefits in two ways:

1) Protection from invading microbes (through competitive inhibition or microbial antagonism) 2) Produce vitamins

What are the chemical factors of innate immunity?

1) Sebum 2) Perspiration (Lysozyme) 3) Earwax 4) Saliva 5) Gastric Juice 6) Vaginal secretions 7) Urine

What is the mechanism involved in the development of fever? Endotoxins and the pyrogenic response. Place in order: 1. Macrophage ingests a gram-negative bacterium 2. Bacterium degraded and endotoxins released macrophage produce cytokines, interleukin-1, and tumor necrosis factor alpha (TNF-a). 3. cytokines induce the hypothalamus to produce prostaglandins, which reset the body's "thermostat" to a high temperature, producing fever. 4. cytokines are released in to the blood stream by the macrophages through which they travel to the hypothalamus, the temperature control system.

1, 2, 4, 3

What are the 3 ways normal microbiota provide resistance to diseases?

1. *Competitive exclusion* with invading pathogenic microbes 2. Produce substances that *kill* invading pathogenic microbes 3. Aid in *development* of immune system

What are the types of exotoxins?

1. A-B toxins 2. Membrane-disrupting toxins 3. Superantigen 4. Genotoxins

What are the 4 stages of an inflammatory response?

1. Acute Vascular Response 2. Acute Cellular Response 3. Chronic Cellular Response 4. Resolution

What are the 5 results of an antigen-antibody complex?

1. Agglutination 2. Opsonization 3. Antibody-dependent cell-mediated cytotoxicity 4. Neutralization 5. Activation of compliment system

How is adaptive immunity acquired?

1. Artificially = Vaccination 2. Naturally = Illness

What are the 5 steps of APC selection?

1. B cell receptors recognize and attach to an antigen 2. Antigen is internalized to B cell 3. Fragments of the antigen are presented on MHC II proteins on the surface 4. T (helper) cells recognize and contact the displayed antigen on the surface and release cytokines that activate B cell 5. B cell undergoes proliferation --> Memory B cells and Plasma B cells

What are the two structures which help pathogens evade host defenses?

1. Capsule 2. Cell Wall Components

What are the 4 mechanisms of phagocytosis?

1. Chemotaxis 2. Adherence 3. Ingestion 4. Digestion

What are conjugate vaccines?

1. Created by attatching bacterial capsule polysaccharides to a toxoid. 2. elicit a strong immune response for children

What are the functions of inflammation?

1. Destroy and remove the injuring agent, if possible 2. Contain the infection (wall it off) to limit damage 3. Repair or replace damaged tissue

How is inflammation involved in providing innate immunity?

1. Destroys injurious agent, and removes it (agent and its by products. 2. Limits its effect on the body by walling off. 3. Repairs and replaces tissue damage by the injurious agent.

What works do epidemiologist perform?

1. Determine etiology of disease 2. Identify important factors concerning the spread of the disease 3. Develop methods for controlling a disease 4. Assemble data and graph to outline the incident (& prevalence) of the disease

What is the role of the lymphatic system?

1. Drains excess fluid from ECF to blood vessels 2. Destroys pathogen germs and foreign substances 3. Provides immunity

What are the drugs used in the treatment of AIDS?

1. Fusion/ cell entry inhibitors: Enfuvirtide, Maraviroc 2. Reverse Transcriptase inhibitors: NRTIs ( Tenofovir, Emtricitabine); NNRTIs: ( Efavirenz) 3. Integrate Inhibitors: Raltegravir 4. Protease Inhibitors: Atazanavir, Indinavir, Saquinavir 5. Maturation Inhibitors 6. Tetherins

What are the 4 classes of drugs used to inhibit HIV life cycle?

1. Fusion/entry inhibitor 2. Reverse transcriptase inhibitors 3. Integrase inhibitors 4. Protease inhibitors

What are the different types of antibodies?

1. IgG 2. IgA 3. IgM 4. IgE 5. IgD

List the 5 different stages of disease progression:

1. Incubation 2. Prodromal 3. Illness 4. Decline 5. Convalescence

What are the different types of vaccines and their characteristics? Be able to identify these types of vaccines from a set of examples.

1. Live attenuated vaccines - weakened pathogens; closely mimic an actual infection; confers lifelong cellular and humoral immunity 2. Inactivated killed vaccines - safer than live vaccines; require repeated booster doses; induce mostly humoral immunity 3. Subunit vaccines - use antigenic fragments to stimulate an immune response

What players are involved in clonal selection of APC?

1. MHC 2. APC 3. Cytokines 4. Helper T-Cells

Examples of Autoimmune responses and their causes?

1. Multiple Sclerosis 2. Graves Disease 3. Myasthenia Gravis 4. Systemic Lupus Erythematous 5. Rheumatoid Arthritis 6. Insulin-Dependent Diabetes Mellitus 7. Psoriasis & Psoriatic Arthritis

types of adaptive immunity

1. Naturally-acquired a. Active- getting infection b. Passive- Ig passed from mom to fetus (or baby thru milk) 2. Articifially-acquired a. Active- getting shots b. Passive- injection of Ig

What are the three types of granulocytes?

1. Neutrophils 2. Eosinophils 3. Basophils

How is a fever initiated?

1. Pyrogens reset the hypothalamus to a higher setting

What are the 3 regions of an antibody?

1. Stem Region 2. Hinge Region 3. Antigen Binding site

In which ways pathogens escape from the host defenses?

1. Structure which help pathogens evade host defenses 2. Cell wall components 3. Antigenic Variation 4. Penetration into Host Cytoskeleton

What are the 7 principal cells that function in cell-mediated immunity?

1. T Helper Cell (T_H_1) 2. T Helper Cell (T_H_2) 3. T Helper Cell (T_H_17) 4. Cytotoxic T Lymphocyte (CTL) 5. T regulatory Cell (T_reg) 6. Activated Macrophage 7. Natural Killer Cell (NK cell)

What are the different classes of T cells?

1. T Helper Cells (CD4+ T cells) - T helper cells (TH) - Cytokines signaling with B cells; interact directly with antigens - Bind MHC class 11 molecules on B cells and APC's

In which ways pathogens can make the body sick?

1. Using host nutrients 2. Causing direct damage 3. Producing toxins (Exotoxins & Endotoxins) 4. Inducing hypersensitivity reactions

What are the 4 types of hypersensitivity?

1. anaphylactic 2. cytotoxic 3. immune complex 4. delayed cell-mediated

What do activated macrophages do?

1. phagocytize invader through endocytosis 2. digest invader with enzymes 3. present pieces of invader to other cells using MHC protein

What happens in the *third stage* of an inflammatory response? (Chronic Cellular Response)

>Occurs days after *severe* injury Macrophages appear Macrophages are involved in microbial killing, in clearing up cellular and tissue debris, and remodeling the tissues.

What happens in the *second stage* of an inflammatory response? (Acute Cellular Response)

>Occurs hours after injury 1) Appearance of granulocytes, particularly neutrophils, in the tissues A) margination = Attached to cells in blood vessels B) diapedesis = Crossing into other tissues

What happens in the *first stage* of an inflammatory response? (Acute Vascular Response)

>Occurs within seconds to minutes after injury >Vasodilation and increased capillary permeability which leads to: 1) increased blood flow 2) redness ( erythema) 3) the entry of fluid into the tissues

What is the compliment system?

A cascade of reactions occur in response to stimuli which indicate foreign material - Serum proteins produced by the liver that assist the immune system in destroying microbes.

What is an autoimmune disease?

A disease in which the body's immune system attacks healthy cells.

What is selective toxicity?

A drug that kills harmful microbes without damaging the host

Syndrome?

A group of specific symptoms typical of a particular disease or condition

What is localized anaphylaxis?

A reaction limited to the site of allergen exposure (usually oral or nasal routes)

What is commensalism?

A relationship in which one organism benefits and the other is neither helped nor harmed

What is a retrovirus?

A retrovirus is an RNA virus that replicates in a host cell through the process of reverse transcription

Phagocytes

A type of white blood cell that ingests invading microbes

What are barriers to entry?

A) Skin - Dermis and epidermis B) Mucous Membranes - line internal organs C) Defecation (diarrhea incl.) and vomiting

What is toxigenicity?

Ability of a microorganism to produce a toxin.

What is immunity?

Ability to ward off disease

Contagious?

Able to be passed easily from one person to another.

Graves disease

Abnormal antibodies in the thyroid produce excessive amounts of hormones

What is fever?

Abnormally high body temperature, a component of the second line of defense.

How is the complement system involved in Type 2 reaction?

Activation of complement by the combination of IgG or IgM antibodies with an antigenic cell, which causes cell lysis or damage by macrophages

The difference between innate immunity and adaptive immunity is that?

Adaptive immunity has a memory component while innate immunity does not

How do phagocytes attach to pathogens?

Adherence

Bloodtype B transfused to patient with bloodtype A Which is NOT true this case

Agglutinated blood cells will trigger phagocytosis

Uncoating, genome integration, and nucleic acid synthesis inhibitors

Amantadine/ Zimantadine, Zidovudine ' AZT'/ Tenofovir/ Emtricitabine, Acyclovir/ Ganciclovir/ Ribavirin/ Lamivudine Adefovir/ Dipivoxil, Cidofovir

Inhibitors of protein synthesis?

Aminoglycosides Tetracyclines Chloramphenicol Macrolides

Disease

An abnormal state in which the body is not functioning normally

What is a lysozyme?

An enzyme capable of breaking down cell walls of bacteria found in saliva, mucous secretions, and tears

Type 3: what is an immune complex?

An excess amount of antibodies (usually IgG) relative to the antigens cause formation of complement-fixing complexes that can be removed from the body by phagocytosis. However, when there is an excess of antigens, some of the soluble complexes fix with complement & are not removed by phagocytosis, they circulate through the blood, & become attached to the basement membrane of endothelium.

What is sebum?

An oily substance secreted by sebaceous glands to moisturize skin. *Creates an acidic environment on skin*

What is a cytokine storm?

An overreaction of the immune system caused by a virus or bacteria that causes shock in the patient, and can cause death

Vectors

Animals or insects that carry pathogens from person to person

May be involved in providing innate immunity to the body EXCEPT

Antibodies

What is an antitoxin?

Antibodies against a specific toxin

Myasthenia gravis

Antibodies coat acetylcholine receptors; muscles fail to receive nerve signals

What is a Cytotoxic Autoimmune Response?

Antibodies react with cell-surface antigens (Graves disease + Myasthenia gravis)

What is the classical pathway?

Antibody bound to pathogen binds complement

What are plasma cells?

Antibody producing B cells

Type 2: what happens when there is incompatible blood transfusion?

Antigen- antibody reaction causes agglutination (clumping) & activates complement, which in turn causes lysis of the donor's RBC's as they enter the recipient's system. Therefore, whole blood whole blood is not used in transfusion.

What is the stimulus or trigger for The Classical pathway?

Antigen-Antibody reaction

Know the general structure of an antibody. Which part in the antibody the antigens binds to?

Antigens bind to the epitope of the antibody

Haptens

Antigens too small to provoke immune responses; attach to carrier molecules

These events will occur resulting to the destruction of the pathogens except?

Apoptosis

Virus infected cells tagged as targets for cytotoxic T Lymphocytes will be destroyed or killed through?

Apoptosis

TLR (toll-like receptors)

Are attached to the phagocyte, they adhere to the PAMPs (pathogen-associated molecular patterns) on the microbe. This adherence initiates phagocytosis and induces the phagocyte to release cytokines that recruit additional phagocytes.

What is an endotoxin?

Associated with some Gram-negative bacteria. - An "endotoxin" is a toxin that is a structural molecule of the bacteria that is recognized by the immune system.

What is adherence?

Attachment of a phagocyte to the surface of the microorganism (PAMP + TLRs)

IgD

B cell receptor

Bacteremia

Bacteria in the blood

Why is the secondary immune response quicker?

Because *memory B-cells* and *memory T-cells* can recognize the antigen and produce the correct antibodies quicker.

What is chill?

Body constricts the blood vessels, and shivering occurs, raising body temperature.

What is crisis?

Body temperature falls, vasodilation and sweating occur.

Which of the following diseases is NOT spread by droplet infection?

Botulism

Collagenase

Breaks down collagen

How do vaginal secretions aid in innate immunity?

By moving microorganisms out of the vagina.

How does an endotoxin cause fever?

By stimulating macrophages to release cytokines in high concentrations, especially interleukin 1. Interleukin 1 travels to hypothalamus, causing production of prostaglandins.

During inflammation stimulated by compliment , what triggers release of histamine?

C3a and C5a bind to mast cell

What does a helper T cell do?

Can "read" these signals and tell what kind of particle the macrophage has eaten! if the T cell determines that the macrophage has eaten something harmful, it can trigger a powerful reaction towards the specific pathogen

Contagious

Can be directly transmitted from human to human Examples: influenza, measles, tuberculosis, syphilis

Non-communicable

Cannot be transmitted (can be infectious and noninfectious)

Which structure prevents pathogenic bact being engulfed by macrophages

Capsule

What is the lectin pathway?

Carbohydrate components of microbes bind complement

What is cytolysis?

Cell bursting.

Endotoxins like lipid A are found in which part of pathogenic bacteria

Cell wall

What is T Cells function?

Cell-mediated immunity

Antigen-presenting cells (APCs)

Cells such as B cells, macrophages, and dendritic cells can present exogenous antigens to naive or memory T cells, activating them

Plasma cells

Cells that develop from B cells and produce antibodies.

Symptoms?

Changes people feel that are not measurable or observed by others.

What is chemotaxis?

Chemical signals attract phagocytes to microorganisms

Antigens (aka immunogens)

Chemicals (mostly proteins) that stimulate antibody production

What are Adjuvants?

Chemicals added to increase effective antigenicity Added substances that increase the antigenicity of the vaccine

Leucocytes to site of injury, this response to the leucocytes is called

Chemotaxis

Which of these factors increases the risk for an individual to get nosocomial infections?

Chemotherapy

What are the classes of MHC (Major histocompatibility complex) ?

Class I: Play a KEY ROLE in cytoxic cell function (CD8) *Identify Self* Class II: PRESENT ON ANTIGEN-PRESENTING cells (CD4)

Coagulase

Coagulates fibrinogen

What is the stroma?

Connective tissue of an organ that is replaced in Resolution

Which one exemplifies type IV hypersensitivity reaction?

Contact dermatitis

Communicable include:

Contagious & Noncontagious

A-B toxins

Contain an enzyme component (A part) and a binding component (B part)

What are cytokines and their role in humoral adaptive immunity?

Cytokines are chemicals released by cells for intercellular communication (signaling molecules) they function as chemical messengers

"Aids drug cocktail" may inhibit any these stages of virus life cycle EXCEPT

DNA unpacking

Genotoxins

Damage DNA (causing mutations, disrupting cell division, and leading to cancer)

What is innate immunity?

Defenses against *any pathogen* that are rapid and present at birth

IgA proteases

Destroy IgA antibodies (N. Gonorrhoeae and N. meningitidis)

Kinase

Digest fibrin clots

Hyaluronidase

Digests polysaccharides that hold cells together

Disruption to host cell function, using host cell nutrients, producing waste products, and multiplying in host cells causing rupture are examples of?

Direct damage to host cells

What do cytotoxic T cells do?

Directly attack and kill other cells *on contact*

Zoonotic

Disease that can be transmitted between animals and humans

What are examples of Syndromes?

Down Syndrome, AIDS

Agents affecting fungal cell walls?

Echinocandins

Who completed the first immunization?

Edward Jenner

CTL destroys virus infected cells, what serves as "surface tag" marking target cells?

Endogenous antigens presented on the self cells surface by MHC class I protein

How is digestion of microorganisms achieved during phagocytosis?

Enzymes (lysosomes) digest microbe in the phagolysosome

Specific portion of the antigens These portions are called

Epitopes

What is a superantigen?

Exotoxin that activates T cells in a nonspecific and uncontrolled manner

What is a Genotoxin?

Exotoxin that causes damage to DNA (leads to mutations that cause cancer)

How does peristalsis, defecation, vomiting, and diarrhea aid in the innate immunity?

Expels microbes

Primary infection

Exposure of the body to pathogens for the 1st time results to a disease Ex: chicken pox, tuberculosis, abscess

IgA

Expressed in mucosal tissues. Forms dimers after secretion, secreted into mucus, tears, and salvia

A person with an autoimmune disease is considered as immunocompromised? True or False

False

Antibacterials that inhibit cell wall synthesis can be used to treat mycoses TRUE or FALSE

False

Autoimmune diseases result hypersensitivity reactions of immune system to antigens True or False

False

Gram positive bacteria may produce endotoxins.

False

HIV AIDs immunes system has been prviously exposed/sensitized to? True or False

False

The antiviral proteins (AVPs), produces by cells responding to interferons, will be effective in removing the virus in cells from the cells that have been actively infected with the virus.

False

Signs and Symptoms of inflammation EXCEPT/ Activation of the complement system may produce these outcomes EXCEPT?

Fever

What is a fever? How is a fever involved in providing innate immunity?

Fever is a systemic response that is an abnormally high temperature in the body which is another component of the secondary line of defense.

innate immunity

First and second line of defense. Rapid response. No memory. Present at birth. Prevents microbes from entering the body and helps eliminate them if they do. defenses against any pathogen

Agents affecting Nucleic Acids?

Flucytosine

Indirect contact

Fomites (through surgical instruments, stethoscopes, cuffs, etc.), or airborne ( ventilation system)

How does sebum defend against bacteria?

Forms a protective film and lowers skin pH, making it inhibitory for some bacteria

What are Endotoxins?

Found in gram-negative bacteria as part of the bacterial cell wall.

What is IgA?

Found: Mucous membrane (saliva, tears), GI tract, Breast milk Dimer in secretions --> has 8 binding sites Function: Prevents microbial attachments to mucous membranes

What is IgE?

Found: On mast cells and in blood Functions: Cause release of histamines in allergic reactions

What are the portals of exit?

Generally the same as the portals of entry for given microbe. -mucous membranes -skin -parenteral route

Major Histocompatibility Complex (MHC)

Genes encode molecules on the cell surface

What is the role of the capsule?

Glycocalyx around cell wall impairs phagocytosis

Capsule

Glycocalyx around the cell wall impair phagocytosis *Streptococcus pneumoniae- pneumonia *Haemophilus influenzas- pneumonia meningitis *Bacillus anthracis- anthrax *Yersinia pest is- plague

What are the two main categories of leukocytes?

Granulocytes and Agranulocytes

Syndrome

Group of signs and symptoms suggesting the presence of defense Examples: -AIDS -SARS -MERS -ARDS

Which cases shows case of permanent acquired immunodefieciency?

HIV AIDS

Whch will not confer adaptive immunity?

Having fever and inflammation

Direct contact

Healthcare workers to patient; patient to patient

IgG

Highest opsonization and neutralization activities, classified into four subclasses (1,2,3,4). Main blood antibody

Which of these chemical substances is involved in causing inflammation?

Histamines

Mechanical transmission

Houseflies physically carrying pathogens on their legs will transmit or transfer the pathogens when they touch food items.

How does gastric juice defend against bacteria?

Hydrochloric acids low pH destroys most bacteria and toxins

Which of these human interferons has an antibacterial activity?

INF gamma

Type 2: what happens in Hemolytic disease of the new born?

If whole blood from a type O donor were given to a type B recipient, the anti- B antibodies in the donor would immediately react with the recipient cells (that have B antigens), fixing complement & lysis cells.

Which antibodies protect the fetus and newborns?

IgG

What are the 5 types of antibodies?

IgG IgM IgA IgD IgE

Type 2: which antibodies are involved?

IgG or IgM

What is opsonization?

Immune adherence promotes the attachment of a phagocyte to a microbe by coating the microbe with certain serum proteins; making ingestion easier

Systemic lupus erythematosus (SLE)

Immune complexes form in the kidney glomeruli

Which one evokes the child's primary immune response?

Immunogens

Bacteriocidal?

Kills bacteria

What is susceptibility?

Lack of resistance to a disease

A disease in which the causative agent remains inactive for a time before producing symptoms is referred to as

Latent

What is the stimulus or trigger for The Lectin Pathway?

Lectin binds to mannose on surface of microbe

Which bacterial pathogen is considered highly infectious _______________ and which one is least infectious _____________ ?

Legionella pneumophila Treponema

Examples of Membrane-disrupting toxins?

Leukocidins - kill phagocytic leukocytes Hemolysins - kill erythrocytes by forming protein channels Streptolysins - hemolysins produced by streptococci

What test is used to detect endotoxins?

Limulus amebocyte lysate assay

What is the stimulus or trigger for The Alternative Pathway?

Lipid carbohydrate complex

Injury to plasma membrane?

Lipopeptides Polymyxin B

? Which phase of bacterial growth curve more exotoxins are produced and released by the pathogens? ? In which phase of the bacterial growth curve, the pathogens produce and release high amount of exotoxins?

Log phase

Memory cells

Long-lived lymphocyte capable of responding to a particular antigen on its reintroduction, long after the exposure that prompted its production.

Which white blood cells are non-phagocytic?

Lymphocytes

What are the three types of agranulocytes?

Lymphocytes Dendritic cells Monocytes

What does a membrane-disrupting toxin do?

Lyses host cell by disrupting plasma membrane

The antigen gragment on surface of its plasma membrane thru which protein?

MHC class II

These events result to the production of fever in a patient following infection with gram negative bacterial pathogens

Macrophage digests bacterial cell Lipid A released from the bacterial cell wall Macrophage releases interleukin 1 and tumor necrosis factor alpha to the bloodstream Interleukin-1 and tumor necrosis factor alpha stimulate the cells in the hypothalamus to release prostaglandins Prostaglandins reset thermostat to higher tempature

Penetration into the Host Cell Cytoskeleton

Major component of the cytoskeleton is a protein called actin, which is used by some microbes to penetrate host cells and by others to move through and between host cells. Bacteria may produce proteins that alter the actin of the host cell's cytoskeleton allowing bacteria into the cell

Entry and fusion inhibitors?

Maraviroc Enfuvirtide

Cell releases histamines and other mediator molecules resulting to a localized anaphylactic reaction?

Mast cells

Psoriasis and psoriatic arthritis

Mediated by T cells that attack tissues; autoimmune disorders of the skin

What is normal microbiota?

Microbes normally present in and on the human body

Prevent the invasion of the body by the pathogens during infection?

Microbial antagonism

What is the body's normal microbiota?

Microorganisms found colonizing the body without causing a disease

Pathogen-associated molecular patterns (PAMPs)

Molecules present on pathogens and not self

What is IgD?

Monomer attached to surface of B cells Function: B cell receptor

Illness period

Most severe signs and symptoms

What are different portals of entry?

Mucous Membranes Skin Parenteral Route

Which is NOT considered part of 2nd line defense providing body innate immunity?

Mucous membrane

Which of these pathogens can escape from the host immune responses by being able to survive inside the phagocytes? check all

Mycobacterium tuberculosis Plasmodium Rickettsia species Coxiella burnetti

Multiple sclerosis

Myelin sheath destruction. disruptions in nerve impulse conduction

Which of the following is NOT an antigen presenting cell?

Natural cell killer

Which of these white blood cells are not capable of phagocytosis? Check all those that apply. neutrophils eosinophils Natural killer cells basophils lymphocytes dendritic cells

Natural killer cells, basophils, lymphocytes

Different types of Granulocytes?

Neutrophils Eosinophils Basophils

The different types of white blood cells

Neutrophils Lymphocytes Basophils Eosinophils

Which white blood cells are active in phagocytosis?

Neutrophils, Eosinophils, Macrophages, and Dendritric cells

Which one exemplifies naturally acquired passive adaptive immunity?

Newborn receiving antibodies from moms milk

What is the difference between transient and normal microbiota?

Normal is permanent while transient is temporary (could include the pathogen)

Pseudomonas bacteria colonized the bile duct of a patient following his liver transplant surgery. This is an example of a

Nosocomial infection

Noninfectious

Not resulting from infections Examples: cancer, osteoarthritis

Mortality rate

Number of deaths from the disease in relation to the population in a given time in relation to the total population

Morbidity rate

Number of people affected in relation to the total population in a given time period

Signs

Objective(measurable), evidence of disease Examples: -Erythema -Changes in blood pressure -Fever -Blood in stool -Change in blood counts -Swelling -Weight loss

What is a secondary response?

Occurs after the second exposure with an antigen

Type 1 (Anaphylactic) Reactions

Occurs minutes after a person sensitized to an antigen is reexposed to that antigen; Antigens combine with IgE antibodies

Which of these bacterial structures are associated with the pathogenicity of some bacteria? check all that apply

Opa protein myocolic acid toxins capsule

What is opsonization? How does opsonization facilitate phagocytosis?

Opsonization is the process of coating the microorganism with a serum which allows it to be more readily phagocytize by promoting the attachment of the microorganism to the phagocyte.

How is ingestion of microorganisms achieved during phagocytosis?

Opsonization, microorganism is coated with serum proteins, making ingestion easier

What happens in the *fourth stage* of an inflammatory response? (Resolution)

Over the next few weeks, resolution may occur, meaning that the normal tissue architecture is restored.

Epitope (aka antigenic determinant)

Part of antigen where antibodies attach to

What is a PAMP? What are TLRs?

Pathogen Associated Molecular Pattern Toll Like Receptors

Antigenic variation

Pathogens alter their surface antigens (and antibodies are rendered ineffective)

Local infection

Pathogens are limited to a small area of the body Ex: boils, appendicitis, pharyngitis, etc.

What is IgM?

Pentamer(10 binding sites)- Largest and heaviest First to respond to infection - First to die too Function: Cause clumping of cells and viruses

In which period of disease development, the high amount of exotoxins are released by the pathogens?

Period of illness

What are the Second Line of Defenses?

Phagocytes, inflammation, fever, and Antimicrobial substances.

What are toxins?

Poisonous substances produced by microorganisms.

The United States has topped, in terms of the highest cases of COVID 19 infections/diseases, throughout the world. Everyday, new cases of infections are being reported. The total number of cases including both the new and old cases reported each day represents the

Prevalence of the disease

What do fusion/entry inhibitors do?

Prevent HIV from binding to receptors on T cells, or entering the cell

Bacteriostatic

Prevent microbes bacterial growth

What is apoptosis?

Process of programmed cell death

What does T Helper Cell 1 do?

Produce IFN_g that: --activates macrophages --enhances compliment --stimulates antibody production --promotes phagocytosis

What is the B cells function?

Produce antibodies

What do NK (Natural Killer) cells do?

Produce perforins (pore-forming proteins) that target cancer & virus cells. Perforins cause cells to lyse

IgM

Produced first upon antigen invasion, increases transiently, primary response fixes complement, monomer serves as a B-cell receptor

Substance responsible for re-setting bodys thermostat during fever production?

Prostaglandin

Antibodies (aka immunoglobulins)

Proteins produced in response to certain antigens

What are Exotoxins?

Proteins produced inside by both gram positive and negative bacteria, as a metabolic by product.

Exotoxins

Proteins secreted by certain bacteria, soluble in bodily fluids, destroy host cells and inhibit metabolic functions

What does T Helper Cell 17 do?

Recruits neutrophils Stimulates production of antimicrobial proteins

What does a T regulatory cell do?

Regulates immune response --maintains self-tolerance

Endotoxins

Released only when bacteria die and their cell walls break down

What are the sources of pathogens/infections?

Reservoirs of infection-the source. These are needed for continuous presence of disease.

Immunity

Resistance or protection against pathogens, ability to ward off disease.

What is the role of M protein?

Resists phagocytosis (Streptococcus pyogenes)

The ciliary escalator is a defense system of which tract?

Respiratory tract by moving trapped microbes in the mucus away from the lungs.

What are the different mucous membranes?

Respiratory tract, gastrointestinal trac, genitourinary tract, conjuctiva

Infectious

Resulting from infections (pathogen invading the body) Examples: tetanus, botulism

Selective toxicity?

Selectively finding and destroying pathogens without damaging the host

Type 3: what are the consequences resulting from presence of immune complexes in certain parts of the body?

Serum sickness, systemic lupus erythematous Antibodies against soluble antigens in the serum form immune complexes that lodge in the basement embrace beneath the cell; then activate complement, causing inflammation Ex: of consequence due to immune complexes: Glomerulonephritis (inflammatory damage to the kidney glomeruli due to immune complexes as a result of infection)

What is the role of CDC (Centers for disease control and prevention) in epidemiology?

Serves as the central source of epidemiological information in the U.S. It publishes the Morbidity and Mortality Weekly Report (MMWR). The MMWR contains data on morbidity and mortality, also includes reports of disease outbreaks, case histories of special interest, and summaries of the status of particular diseases during a recent period. Often includes recommendations for procedures for diagnosis, immunizations, and treatment.

Proteins that can "snatch" iron from iron-transport proteins in the body are called?

Siderophores

What are haptens?

Small molecules that become antigenic only when they bind to red blood cells or platelets

What are immune complex reactions?

Soluble antigens combine with IgG and IgM forming complexes too small to be removed by phagocytes; release chemotactic factors leading to inflammation and tissue destruction (Ex: sickle cell)

Epidemic

Sometimes referred to as an outbreak. When a significant number of individuals in a location develop the disease at numbers higher than the expected normal occurrence. Ex: flu, measles, Zika, etc..

Subacute disease

Somewhat between acute and chronic, symptoms are less pronounced and more prolonged than acute. Ex: subacute endocarditis, diminished intellectual function and loss of nervous function

A community celebrates the victory of Kansas City Chiefs in the recently concluded Superbowl 52, with a bash, partying in salads, burgers, hotdogs, ceviche, and a lot more. The following day, many individuals especially the elderly who attended the party, were hospitalized for common symptoms of diarrhea, vomiting and fever. What type of disease occurrence does this demonstrate?

Sporadic

Focal infection

Starts with local infection then the pathogen spreads systemically Ex: appendicitis is a local infection but when the inflamed appendix ruptures, bacteria are spread out within the peritoneum resulting in peritonitis, a systemic infection.

What does T Helper Cell 2 do?

Stimulates production of eosinophils, IgM, and IgE

Symptoms

Subjective; felt by the patient Examples: -Paresthesia (tingling, pricking, or buming sensation in the skin) -Nausea (ibs food poisoning, dehydration) -Tiredness or weakness

What are antigens?

Substance that evoke production of antibodies (Parts of a microbe, not the whole thing)

Vaccine which contains only the antigen of the pathogen is called

Subunit vaccine

What are subunit vaccines?

Subunit vaccines do not use whole cells; they use only the *most antigenic components of a pathogen* Hepatitis B HPV (Human papillomavirus) Whooping cough Shingles

Recombinant vaccines

Subunit vaccines produced by genetic modification

What is systemic anaphylaxis?

Sudden respiratory and circulatory disruption that can be fatal Treat w/ epinephrine (*anaphylactic shock*)

Competitive inhibitors of synthesis of Essential Metabolites

Sulfonamides

What are vaccines?

Suspension of organisms or fragments of organisms that induce immunity

Acute?

Symptoms develop rapidly but the disease lasts only a short time.

Chronic?

Symptoms develop slowly. Body's reactions are less severe, but disease is likely to continue to recur for long periods.

Antimicrobial drugs

Synthetic substances that interfere with the growth of microbes

Insulin dependent diabetes mellitus

T cell destruction of insulin-secreting cells

What are the principal cells involved in cell-mediated immunity?

T cells or T lymphocytes - To fight against intracellular pathogens

Surface of its plasma membrane for the ______ cell to recognize it

T helper

Deletion of immature T cells b4 released from the Thymus to bloodstream?

T regulatory cells

When the phagocyte adheres to the pathogen, this is possible because of the interaction between their PAMP (pathogen-associated molecular pattern) with the host cells' ______________.

TLR (toll-like-receptor)

Chronic disease

The disease that develops gradually, the reduce may reoccur from time to time Ex: chronic bronchitis, hepatitis B, tuberculosis

What is a primary immune response?

The first time the immune system is triggered against a foreign substance. An antigen is encountered by the host for the first time, naive B cells need to be activated and proliferate before an effective antibody response can be generated. Mainly produces IgM antibodies

What is the parenchyma?

The functional tissue of an organ that is replaced in Resolution

What is a secondary immune response?

The immune response generated upon secondary and subsequent encounters with a pathogen. It is *faster* and *more effective*

Why is the secondary immune response more rapid compared to the primary response?

The initial encounter of a naive immune-competent lymphocyte with an antigen induces a primary immune response; but a later contact of the host with the same antigen will induce a more rapid and heightened secondary response, because of the memory cells. The amplified population of the memory cells accounts for the rapidity and intensity that distinguishes a secondary response from the primary response.

What vitamins are produced by bacteria?

The large intestine contains E. coli that synthesizes vitamin K and some B vitamins.

Mortality

The number of deaths caused by a particular disease, illness, or other environmental factors.

Prevalence

The number or proportion of cases of a particular disease or condition present in a population at a given time.

What is an epitope?

The part of an antigen molecule to which an antibody attaches itself (Think LEGO pieces)

Incidence

The ratio of new cases of the diseases in the population Ex: number of new COVID 19 cases reported daily

What is epidemiology?

The studies of when and where diseases occur and how these diseases are transmitted in the population.

What is Chemotherapy?

The use of drugs to treat a disease

What do reverse transcriptase inhibitors do?

They act against an enzyme HIV uses in its replication cycle.

What are live attenuated vaccines?

They are weakened but still active organisms Smallpox yellow fever chickenpox (VZV) Sabin polio virus MMR Influenza (intranasal).

adaptive immunity

Third line of defense . Has memory component. Specific response to a specific microbe. immunity or resistance to a specific pathogen

What is humoral immunity?

This is when antibodies attack antigens that are free in the plasma *Antibody-mediated immunity*

What are Delayed Hypersensitivity Reactions?

Tissue damage occurs from sensitized T-cells that attack antigens or release cytokines (Ex: poison ivy, transplant rejections, TB skin test)

What is an Exotoxin?

Toxin produce and secreted by bacteria that destroy host cells and inhibit metabolic functions

Antimicrobial substances confer innate immunity to the body EXCEPT

Toxins

Toxemia

Toxins in the blood (as occurs in Tetanus)

Vaccines against exotoxins produced by pathogens such as tetanus, pertusses and diphtheria givn to young adults form of ?

Toxoid vaccines

Toll-like receptors (TLRs)

Transmembrane protein of immune cells that recognizes pathogens and activates an immune response directed against those pathogens

Animal reservoirs

Transmitted by sick animals, or animals harboring the pathogen as intermediate hosts Ex: rabies, Lyme disease, COVID 19, malaria, etc.

Human reservoirs

Transmitted by sick people; may be asymptomatic

Humoral immunity may involved in protecting body against extracellular pathogens? true or false

True

Immunity against specific diseases can only be acquired? True or False

True

Which of these pathogens undergo antigenic shift in order for them to circumvent or evade the host defenses? Check all those that apply.

Trypanosoma brucei Neisseria gonorrhoeae influenza virus

Number of antigen binding sites in antibodies represent the _____ of the antibodies

Valence

Noncontagious

Vector borne, or vehicle borne Examples: malaria, Zika virus disease

Viremia

Viruses in the blood

How do antibodies work in providing immunity? Clue: results of antigen-antibody binding.

When antibodies are bound to antigens of pathogens 1. Agglutination- reduce number of infectious units 2. Opsonization- leads to phagocytosis 3. Antibody- dependent cell-mediated cytotoxicity 4. Neutralization- prevents adhesion to host cells/ mucosa 5. Activation of the complement system ** Antibodies attached to target cell cause destruction by macrophages, eosinophils, and NK cells

Matching Diapedesis Plasma cells Epitope

When monocytes and ne... Antibody producing cells... binding site of antibodies

Systemic infection

When pathogens or their products spread throughout the body through the lymph or blood Ex: sepsis, septicemia, bacteremia, toxemia, viremia

Sporadic

When the disease occurs occasionally. There is no specific pattern in terms of occurrence, as the disease comes and goes. Ex: typhoid fever

Lysogenic cycle of T-even bacteriophage

When the viral DNA integrates into the bacterial host chromosome

What are phagocytes?

White blood cells that ingest pathogens like bacteria.

What are antibodies?

Y-shaped proteins that are produced by B-lymphocytes

Non communicable?

a disease that is not transmitted from one host to another

What are interferons?

a family of cytokines the infected host cell produces to counter viral infections.

Biological transmission

a rabid dog bites a person; mosquito carrying Plasmodium bites a person.

What is an antibiotic?

a substance produced by a microbe that, in small amounts, inhibits another microbe

After the blood clot forms during the inflammation process _______________ forms and is filled with dead cells and body fluids called ________________ this causes swelling.

abscess and pus

What does the A component of the exotoxin do?

active portion, inhibiting protein synthesis

Primary infection?

acute infection that causes the initial illness

What is the role of Opa protein?

allow attachment to host cells (Neisseria gonorrhoeae)

subclinical infection?

an infectious disease not detectable by the usual clinical signs

Which of the following is not a part of the innate immune response?

antibody production

What are cytokines?

any of a number of substances, such as interferon, interleukin, and growth factors, that are secreted by certain cells of the immune system and have an effect on other cells. chemical messengers produced in response to a stimulus

What does the B component of the exotoxin do?

binds to the host cell receptor

What do integrase inhibitors do?

blocks integrase from inserting the viral genome into the DNA of the host cell

Match the exoenzymes with their effects on how they allow bacteria to evade the host defenses: Coagulases Kinases Hyaluronidases

blood clot formation walling off bacteria breaks down blood clot that isolated inf... breaks down polysaccharide that hold..

How does coagulases allow bacteria to evade host defenses?

blood clot formation walling off bacteria from phagocytosis

How does kinases allow bacteria to evade host defenses?

breaks down blood clot that isolated infection

How does hyaluronidases allow bacteria to evade host defenses?

breaks down polysaccharide that holds adjacent cells allowing bacteria to move from cell to another

The potency for a particular bacterial toxin is evaluated in this study. Which one is the LD50 of the toxin?

c

These events result to production of fever in a patient following infection with gram negative bacterial pathogen. a. Lipid A released from the bacterial cell wall b. interleukin-1 and tumor necrosis factor alpha stimulate the cells in the hypothalamus to release prostaglandins c. macrophage digests bacterial cell d. prostaglandins reset thermostat to higher temperature e. macrophage releases interleukin 1 and tumor necrosis factor alpha to the bloodstream Question: what is the correct chronological order of these events?

c a e b d

Communicable

can be transmitted; includes both contagious and noncontagious; mostly infectious

In which ways the pathogen can escape from the host defenses?

capsules, M protein, Opa protein, mycolic acid

human reservoirs

carriers may have inapparent infections or latent diseases

Compliment activation acts in what kind of pattern?

cascade

Latent disease

causative agent remains inactive for a time but then becomes active to produce symptoms of the disease Ex: shingles the virus (varicellovirus) stays dormant in the body

Superantigens

causes an intense immune response due to release of cytokines from host cells (T cells), cytokine storm.

What are the 4 main phases of phagocytosis?

chemotaxis, adherence, ingestion, digestion

Which of these diseases are caused by A-B toxins? Check all those that apply.

cholera, tetanus, diphtheria

How does urine act as a physical factor in the first line of defense?

cleans urethra via flow

Matching Tetanus Striptolysin Diptheria toxin

clostrodium streptococcus corynebacterium

endemic?

constantly present in a population (common cold)

nonliving reservoirs

contaminated food, water, soil, and air

Fever is considered as a protective response. It may result from_____.As one develops fever, the body attempts to increase the temperature in a condition called_____, by shivering and constriction of blood vessels circulating blood to the skin. Once the fever is reached the body undergoes_______which is characterize by excvessive sweating in order to lower the bodys temperature back to normal.

cytokine storm chill crisis

Which T cells serve as the effectors for cell-mediated immunity?

cytotoxic T lumphocytes

These events occur during inflammation. a. injured tissue releases chemical signaling molecules b. regeneration or replacement of injured tissue c. localized edema (or swelling) on the site of injury d. damage or injury to tissue occurs e. blood clot formation What is the correct sequence or or of occurrence of these events?

d a e c b

These events occur during inflammation

damage or injury to tissue occurs injured tissue releases chemical signaling molecules blood clot formation localized edema or swelling on the site of injury regeneration or relpacement of injured tissue

Several inherited deficiencies in the complement system occur in humans. Which of the following affects the most in the body's innate immune response?

deficiency of C3

Epidemiologist

determine etiology, develop methods for controlling the spread, gather data to graph and outline.

Kissing is an example of what kind of transmission?

direct contact

Which of the following is an effect of opsonization?

enhanced phagocytosis

Which of these white blood cells are involved in the body's fight against larger pathogens line parasites?

eosinophils

Which of these do not result or occur when the complement system is activated? fever apoptosis antibodies production lysis of pathogens inflammation

fever, apoptosis, antibodies production

? What is the doorknob or stethoscope called in an indirect contact transmission? ? A needle stick is an example of which type of transmission?

fomite

Pathogens transmitted through the fecal-oral route prefer which mucous membrane as portal of entry?

gastrointestinal tract

streptolysins

hemolysins produced by streptococci

What chemical causes vasodilation and increased permeability in the blood vessels?

histamine- kinins - prostaglandins leukotrienes, and cytokines.

Rheumatoid arthritis

immune complexes form in the joints

latent?

inactive or dormant for a long time then becomes active

Systemic?

infection throughout the body. Spread by blood and lymph.

Hospital acquired infections (HAIs) a.k.a Nosocomial infections are?

infections acquired while receiving treatment in a healthcare setting

Which of these cytokines have antiviral property or characteristics

interferons

incubation period

interval between initial infection and first signs and symptoms

Activation of the complement system can be achieved by these pathways Except?

intrinsic

hemolysins

kill erythrocytes by forming protein channels

leukocidins

kill phagocytic leukocytes

Susceptibility

lack of immunity

What is shock?

life threatening drop in blood pressure

What stimulates the alternative pathway in the complement activation?

lipid-carbohydrate complexes bound to C3

Reservoir of infection?

living or nonliving continuous source of infectious disease

Different types Agranulocytes?

lymphocytes and monocytes

What do membrane disrupting toxin do?

lyse host cells by disrupting plasma membranes

MAC as of consequence of activation of complement system may result to

lysis of pathogens

This chemical found in urine, saliva and sweat can destroy the cell wall of gram positive bacteria?

lysozyme

Endotoxins cause release of massive amount of cytokines, called cytokine storm. Which cells release these cytokines following exposure to endotoxins?

macrophages

What is the major significance of the Koch's work postulates?

microorganisms cause disease.

What is Gastric juice?

mixture of mucus, enzymes, and hydrochloric acid

period of illness

most severe signs and symptoms, now have disease

Inhibitors of cell wall synthesis?

natural penicillins, semisynthetic penicillins, cephalosporins, polypeptide antibiotics, antimycobacterial antibiotics

period of covalence

no signs or symptoms, body returns to its prediseased state

Incubation period?

no signs or symptoms, infected but no disease

Prevalence?

number of new and old cases

Incidence?

number of new cases

Signs?

objective changes that a clinician can observe and measure

Sporadic?

occurring at irregular intervals, No pattern, comes and goes

Secondary infection?

opportunistic infection after a primary infection

On of the consequences of complement system activation is the formation of MAC (membrane attack complex) which will create hole on the surface of pathogens resulting to ___________________.

osmotic lysis of pathogens

In the news recently: Nearly 900 children under 12 are among 1112 cases of HIV infection now confirmed in an outbreak linked to a pediatrician in Rato Dero, Pakistan, who reused syringes and IV drips. Question: What is the portal of entry of the virus to these children?

parenteral

Matching PAMPs TCR TLR

pathogen T cells macrophages

Local?

pathogens are limited to a small area of the body

In which period of disease progression or development, massive amounts of exotoxins are released into the body by toxigenic pathogens?

period of illness

How could encapsulated pathogens escape from the action of phagocytes?

phagocyte cannot attach to the pathogen

What happens during Diapedesis?

phagocytes squeeze between endothelial cells

What happens during margination?

phagocytes stick to endothelium

A child falls and suffers a deep cut on her leg. The cut went through her skin and she is bleeding. Which of the following defense mechanisms will participate in elimination contaminating microbes?

phagocytosis in the inflammatory response

What is toxemia?

presence of toxin in the blood

What is intoxication?

presence of toxin without microbial growth

In the second stage of inflammation why does a blood clot form?

prevent the microbe from spreading

How does earwax act as a first line defense?

prevents microbes from entering the ear by trapping them.

What are siderophores?

proteins secreted by pathogens that bind iron more tightly than host cells

direct contact transmission

requires close association between infected and susceptible host

Virus-like particle (VLP) vaccines

resemble intact viruses but do not contain viral genetic material

What is the role of Waxy lipid (mycolic acid)?

resists digestion (Mycobacterium tuberculosis)

What is an example of subacute?

sclerosing panencephalitis, a rare brain disease characterized by diminished intellectual function and loss of nervous function.

Pathogens that are sexually transmitted leave the body through ________ "secretions of penis and vagina", "conjunctiva", "parenteral route", "kissing"] , while bloodborne pathogens like malaria leave the body through _________ "gastrointestinal tract", "sexual intercourse", "parenteral route", "respiratory droplets"] .

secretions of penis and vagina parenteral route

How does the skin provide defense against pathogens?

shedding and dryness inhibit microbial growth

prodromal period

short period after incubation; early, mild symptoms

Which structures are used by pathogens to sequester iron from host cells?

siderophores

One of the effects of cytokine storm is shock, which is described as

significant reduction in the pressure of the blood.

period of decline

signs and symptoms subside

First line of defense against pathogens

skin and mucous membranes

Communicable?

spread person to person

indirect contact transmission

spreads to a host by a nonliving object called a fomite

Which of these toxins may have pyrogenic (fever producing) effect? check all

superantigens Lipid A

Subacute?

symptoms and signs that are less severe in intensity than acute symptoms

Focal?

systemic infection that began as a local infection

Which of these diseases are caused by A-B toxins? check all

tetanus diphtheria cholera

Attachment of phagocyte to pathogen Attachment is formed by?

the PAMPs of the pathogen and TLR of the phagocyte

In the process when the body, especially the extremities, feels cold chill, during fever development, the chill is a sign that

the body temperature is rising

What is adaptive immunity?

the body's ability to recognize and defend itself against distinct invaders and their products (Memory component)

What is the Endotoxin?

the lipid A found in the lipopolysaccharide (LPS) of the outer membrane of gram negative cell walls

Pathogenesis

the manner in which a disease develops

Pathology

the scientific study of disease

Etiology

the study of the causes of diseases

Epidemiology

the study of when and where diseases occur and how they are transmitted

Convalescence period

tissues are repaired, healing takes place, and body regains strength and recovers

What is the role of the CDC?

to serve as a central source of epidemiological information in the US

Sepsis

toxic inflammatory condition arising from the spread of microbes, especially bacteria or their toxins, from a focus of infection

vehicle transmission

transmission by an inanimate reservoir (food, water, air)

droplet transmission

transmission via airborne droplets less than 1 meter

How does the Mucous Membranes provide defense against pathogens?

traps microbes and prevents tracts from drying out. Lacrimal apparatus creates tears to wash eyes. Saliva prevents colonization.

Match the cases on the left with the type of disease transmission involved *drinking water harboring cyst of E. histolytica ---> *Zika virus-carrying mosquito biting a toddler ---> *inhaling COVID 19 containing respiratory droplets found in cell phones --->

vehicle transmission vector transmission contact transmission

What is the description of chemotaxis?

when a macrophage moves toward a microorganism

What is the description of Diapedesis?

when monocytes leave the blood vessel by squeezing through the endothelial cells.

Match these characteristics of WBC with their description? Diapedesis Margination Chemotaxis

when monocytes leave the bloodstream.. when neutrophil sticks to the endothelium.. when a macrophage moves to the direction...

What is the description of margination?

when neutrophil sticks to the endothelium lining

When are Endotoxins released?

when the cell wall is damaged

Pandemic?

worldwide epidemic

animal reservoirs

zoonoses are diseases transmitted from animals to humans

Limitations of the Koch's Postulates:

1) Some pathogens can cause several disease conditions 2) Some pathogens cause disease only in humans 3) Some microbes have never been cultured

Koch's postulate Finding the cause of the disease (4steps):

1) The same pathogen must be present in every case of the disease 2) The pathogen must be isolated from the diseased host and grown in pure culture 3) The pathogen from the pure culture must cause the disease when it's inoculated into a healthy, susceptible laboratory animal 4) The pathogen must be isolated from the inoculated animal and must be shown to be the original organisım

Multiplication of Animal viruses steps:

1. Attachment: viruses attach to the cell membrane 2. Entry by receptor-mediated endocytosis or fusion 3. Uncoating by viral or host enzymes 4. Biosynthesis: production of nucleic acid and proteins 5. Maturation: nucleic acid and capsid proteins assembly 6. Release by budding (enveloped viruses) or rupture

Epidemiologists conduct 3 basic types of investigations in analyzing the occurrence of the diseases. What are they?

1. Descriptive 2. Analytical 3. Experimental

Describe the events in the one step viral growth curve (3 steps):

1. Inoculation, during which the virions attach to host cells 2. Eclipse, during which entry of the viral genome occurs 3. Burst, when sufficient numbers of new virions are produced and emerged from the host cell

Bacteriophage can multiply by what two alternative mechanisms?

1. Lytic cycle 2. Lysogenic cycle

Sub-clinical infection

(Inapparent infections) asymptomatic infections, the infectious agent does not cause any noticeable illness Ex: varicellovirus (shingles), hepatitis A

Secondary infection

(Opportunistic infections) not from second exposure. These are caused by opportunistic pathogens, usually following a primary infection. Ex: candidiasis, bacterial pneumonia when a patient has the flu, or pneumocystis pneumonia in persons with AIDS (NOTE! when the immune system is down in chemotherapy, or when a person is sick with AIDS' secondary infections will most likely occur)

Define Experimental. One of the 3 types of investigations epidemiologist used in analyzing diseases.

(Started by Florence Nightingale) begins with a hypothesis about a particular disease; experiments to test, the hypothesis are then conducted.

Define Analytical. One of the 3 types of investigations epidemiologist used in analyzing diseases.

(Started by Ignacio Semmelweis) analyzes a particular disease to determine it probable cause. It can use different variables to discover possible routes and rates of infection.

Define Descriptive. One of the 3 types of investigations epidemiologist used in analyzing diseases

(Started by John Snow) entails collecting the data that describe the occurrence of the disease under study

Septicemia

(blood poisoning) is a systemic infection arising from the multiplication of pathogens in the blood

HAIs results from the interaction of what 3 factors:

1. Microorganisms in the hospital environment 2. The compromised or 'weakened' status of the host 3. The chain of transmission in the hospital

Compare: Lytic and Lysogenic life cycles in viruses

1. More viruses are produced within the lytic cycle compared to the lysogenic cycle; which hardly produces less viruses. 2. Undergoes both to reproduce

Lytic cycle of T-bacteriophage steps:

1. Phage attaches the host cell and injects DNA 2. Phage DNA circularizes and enters either Lytic or Lysogenic pathway 3. New phage DNA and proteins are synthesized and assembled into virions 4. Bacterial cells lysis, and virions released

What is HAI

A Healthcare Associated Infection, also called a nosocomial infection

Pandemic

A disease can considered a pandemic if it spreads out to different regions in the globe. Ex: COVID 19 virus which is making people from all over the globe Ill, AIDS, H1N1 (swine flu), SARS, the bubonic plague or Black Death

Endemic

A disease that is constantly present in the population, for this reason a traveler planning to visit to places where a disease is endemic is advised to get a shot against the disease prior to visiting the place. Ex: Malaria, dengue fever, typhoid

Acute disease

Disease develops quickly and it last within a short period of time Ex: acute pneumonia, acute pharyngitis, acute conjunctivitis, etc

The antiviral proteins, produced by cells responding to interferons, will be effective in removing the virus in cells from the cells have been actively infected with the virus? true or false

False

How do you describe the distribution of the microbiota in the body?

Found everywhere in the body, outside the body-skin, mucosa; mouth, etc.

What is a disease?

Impairment of health; abnormal state in which the body is not functioning normally

Morbidity

Incidence of a specific notifiable disease

Non-communicable include:

Infectious & Noninfectious

Which of these WBC are not capable of phagocytosis? check all

Natural killers lymphocytes basophils

What are notifiable infectious diseases?

To gather the accurate information and in order to establish the chain of transmission of a disease- case reporting is required by healthcare workers to report specific diseases to local, state, and national health offices. Ex: Anthrax, Chlamydia, Gonorrhea, HIV, Malaria, Salmonellosis, etc.

Non-living reservoirs

Transmitted by contaminated food, water, or air

Which of these do not result or occur when the complement system is activitate? Check all

apoptosis antibodies production fever

In order for the bacteria to enter into the body they should be able to attach to the host tissue. How do some bacteria attach themselves to the host tissue

binding of ligands or invasins in the surface of pathogen with the receptors on the host cell membrane