BIOCHP15

Process: Local Inflammation

(1) Bacteria enters a break in the skin, (2) Initiated by (innate) nonspecific mechanisms of phagocytosis by toll-like receptors, (3) macrophages and mast cells release cytokines to attract phagocytic neutrophils, (4) complement proteins are activated (also attracts phagocytic cells), (5) inflammation progresses and B lymphocytes produce antibodies against bacterial antigens, (6) the formation of antigen-antibody complexes amplifies opsonization, (7) more phagocytic cells arrive via extravasation from nearby venules. T lymphocytes are the last to arrive. (8) neutrophils may spill protein-digesting enzymes into the surrounding tissues, causing pus. (9) Mast cells secrete heparin, histamine, prostaglandins, leukotrienes, cytokines, and/or TNF-α. (10) Secretions of the mast cells produce warmth, swelling, and pain (as well as recruiting more leukocytes).

Barriers to entry

(1) Epithelial membranes, (2) Mucus membranes, and (3) High Acidity in Stomach

PAMPs: List and describe the most well known type(s)

(1) Lipopolysaccharides (LPS) made from gram-negative pathogenic bacteria and often toxins. Usually found in the envelope of gram-negative bacteria. (2) Peptidoglycan: from gram-positive pathogenic bacteria. From the cell walls of gram-positive bacteria.

List: Major groups of phagocytes

Three major groups. (1) neutrophils, (2) cells of mononuclear phagocyte system, and (3) organ-specific phagocytes.

Interferons: How many are there and list them.

Three types. (1) alpha interferon, (2), beta interferon, and (3) gamma interferon

Describe the role of the thymus in cell-mediated immunity, and identify the different types of T lymphocytes.

Thymus is part of the primary lymphoid organs that play an important role in providing cell mediated immunity. This is the main area where T lymphocytes get matured. Different types of T lymphocytes are processed in the thymus that include killer, helper,, and regulatory. All these function in destroying cells in the body that promote foreign microbes or material in the body. These lymphocytes are cell-mediated (make physical contact with victim).

True or False: When cells are protected by alpha or beta interferons viruses still have the ability to penetrate those protected cells

True

How many categories of the immune system are there? Name them.

Two: Innate (Nonspecific) Immunity and Adaptive (Specific) Immunity

Define: Memory cells

Used in a later infection by the same pathogen. Visually indistinguishable from original cell and are important in active immunity.

Cytotoxic (Killer) T Cells function is to destroy body cells that harbor foreign molecules. What are these foreign molecules?

Usually a pathogen (virus or fungus), but can be due to a malignancy (cancer).

The maximum amount of air that can be expired after maximum inspiration is:

Vital capacity

Define: Active Immunity

When exposed to foreign antigens, immune cells respond by making many copies of themselves. This protects the body from future infections. Development of secondary response against specific pathogens and requires prior exposure.

Define: Extravasation/Diapedesis

Where phagocytic cells (neutrophils and monocytes) squeeze through tiny gaps between adjacent endothelial cells in the vessel wall and connective tissues.

Structure: Antibody

Y-shaped. 2 long, heavy (H) chains joined by 2 shorter, light (L) chains The bottom (Fc) is constant across different antibodies, whereas the top (Fab) varies and allows antigen specificity.

Common autoimmune diseases

rheumatoid arthritis, type 1 diabetes, multiple sclerosis, Grave's disease, pernicious anemia, thyroiditis, psoriasis, and lupus

Causing factors: Autoimmune Diseases

1. An antigen not normally exposed to the immune system becomes exposed. 2. Normally tolerated antigen is combined with a foreign hapten (aspirin combining with platelets). 3. Antibodies are produced aimed at other antibodies. 4. Antibodies produced against foreign antibodies cross-react with self-antigens and begin attacking self cells. 5. Self antigens may be presented to T helper cells along with Class-2 MHC molecules. 6. Inadequate regulatory T cell activity.

Function: Immediate Hypersensitivity

1. Dendritic cells stimulate a class of helper T (TH2) cells to secrete IL-4 and IL-13, which stimulate B and plasma cells to secrete IgE antibodies. 2. These antibodies do not circulate in the blood but attach to mast cells and basophils. 3. Re-exposure to the same allergen will cause these antibodies to bind with it and stimulate the production of histamine, leukotrienes, and prostaglandin D, producing allergy symptoms.

Function: Classic Pathway

1. IgG and IgM activate C1, which splits C4 into two fragments, C4a and C4b. 2. C4b binds to the cell membrane and becomes active, splitting C2 into C2a and C2b. 3. C2a attaches to C4b and cleaves C3 into C3a and C3b. 4. C3b converts C5 into C5a and C5b. 5. C5b and C6−C9 are inserted into the bacterial cell membrane, forming the membrane attack complex. 6. This creates a large pore in the membrane, causing influx of water into the cell (aka lysis).

Function: Alternative Pathway

1. The conversion of C3 is cleaved into C3a and C3b. 2. C3b converts C5 into C5a and C5b. 3.. C5b and C6−C9 are inserted into the bacterial cell membrane, forming the membrane attack complex. 4. This creates a large pore in the membrane, causing influx of water into the cell (aka lysis).

Define: Local Inflammation

A case of inflammation when bacteria/microbe enter a break in the skin. Resulting in warmth, swelling, and pain (red, swollen, pain, ooze: Fishwild lecture).

Define: Clonal selection

A theory. B lymphocytes inherit the ability to produce particular antibodies (and T lymphocytes ability to respond to particular antigens) where this ability is inherited NOT acquired so an individual can produce antibodies against a pathogen even though never previously exposed.

All of the following can bond with hemoglobin except a. HCO3- b. O2- c. H+ d. Co2 e. NO

A. HCO3-

Define: Opsonization

Ability of antibodies to stimulate phagocytosis

Define: Delayed Hypersensitivity

Abnormal T cell response that produces symptoms 24−72 hours after exposure. Cell-mediated. Secretion of lymphokines take place. Example: contact dermatitis caused by poison oak, ivy, or sumac

Define: Adaptive (Specific) Immunity

Acquired ability to defend against specific pathogens after exposure to these pathogens. Mediated by antigens and antibodies. Involves lymphocytes (white blood cells) and changes with exposure to pathogens. This is how we can use vaccines.

Interferons are used to treat what?

Alpha: Used to help treat hepatitis B and C, hairy-cell leukemia, virally induced warts, and kaposi sarcoma. Beta: Used to help treat relapsing reemitting multiple sclerosis. Gamma: Used to help treat chronic granulomatous disease.

Describe the sequence of events by which allergens can produce symptoms of runny nose, skin rash, and asthma.

An allergen produces an allergic reaction by immediate hypersensitivity by binding the allergen with B cells which are transformed into the plasma cells. IgE antibodies are then produced and get attached with the tissue mast cells. Mast cells produce histamines which cause the allergy/hypersensitivity.

B lymphocytes (B cells) produce __________.

Antibodies

What do plasma cells secrete?

Antibodies

Define: Natural Active Immunity

Antibodies are formed in the presence of active infection in body - Duration: lifelong

Define: Immunoglobulins

Antibody proteins. Five subclasses: IgG, IgA, IgM, IgD, and IgE.

Define: Immune Complex Diseases

Antigen-antibody combination that are free rather than attached to bacterial or other cells. These stimulate complement proteins and inflammation. (Usually) Self-regulating because complexes are removed via phagocytosis.

Cytotoxic (Killer) T cells are presented with an ______ and a _______________.

Antigen; class-1 MHC molecule

Define: Artificial Active immunity

Antigens (vaccines) are administered to the person to stimulate antibody production - Duration: many years

Describe properties of antigens

Antigens refer to any foreign material that stimulates the antibodies production upon entrance of the body - resulting in immune response initiation. Antigens include foreign materials such as bacteria, virus, toxins, cells of a transplanted organ or tissue or foreign blood cells.

Define: Interferons

Antiviral polypeptides produced by infected cells. There are three types. New antiviral drugs are being developed using these.

Define: Histocompatibility Antigens

Are on the surface of all body cells (except mature RBCs). Coded for by four genes on chromosome 6 called major histocompatibility complex (MHC). Also can be called HLAs

Function: T cells

Attack host cells that have become infected with a virus or fungus, transplanted human cells, and cancer cells. Do NOT produce antibodies. Must be in close proximity to the victim cell in order to destroy it (undergo cell-mediated immunity).

Distinguish between B and T lymphocytes in terms of their origins and immune functions.

B Lymphocytes: Produced and matured in bone marrow, differentiate to form plasma cells that produce immunoglobulins, provide humoral/antigen-mediated immunity by producing antibodies. T Lymphocytes: Produce in bone marrow from where they migrate to thymus for maturation. Differentiate and multiply to form memory, cytotoxic, regulatory, or helper T cells. Provide cell-mediated immunity. Primary lymphoid organs include the thymus and bone marrow where their main function is to produce B and T lymphocytes and allow them to mature. Secondary lymphoid organs include the spleen and lymph nodes and their function is in differentiation and proliferation of the B and T lymphocytes.

During exercise, which of these statements is true? a. The arterial percent oxyhemoglobin saturation is decreased b. The venous percent oxyhemoglobin saturation is decreased c. The arterial Pco2 is measurably increased d. The arterial pH is measurably decreased

B. The venous percent oxyhemoglobin saturation is decreased

Barriers to entry: Mucus Membranes

Barrier of entry like oil secretion of the skin, tears, sneezing.

Most of the carbon dioxide in the blood is carried in the form of

Bicarbonate

How are PAMPs recognized by cells?

By cells that have receptor proteins. Immune cells have toll-like receptors on their surface to help recognize.

Which of these offers a nonspecific defense against viral infection? a. antibodies b. leukotrienes c. interferon d. histamine

C. Interferon

Which of these statements about intrapulmonary pressure and intrepleural pressure is true? a. The intrapulmonary pressure is always subatmospheric b.The intrapleural pressure is always greater than the intrapulmonary pressure c. The intrapulmonary pressure is greater than the intrapleural pressure d. The intrapleural pressure equals the atmospheric pressure

C. Intrapulmonary pressure is greater than the intrapleural pressure

Which of these statements about the partial pressure of carbon dioxide is true? a. It is higher in the alveoli than in the pulmonary arteries b. It is higher in the systemic arteries than in the tissues c. It is higher in the systemic veins than in the systemic arteries d. It is higher in the pulmonary veins than in the pulmonary arteries

C. It is higher in the systemic veins than in the systemic arteries

If a person were to dive with scuba equipment to a depth of 66 feet, which of the statements would be false? a. The arterial Po2 would be three times normal b. The oxygen content of plasma would be three times normal c. The oxygen content of whole blood would be three times normal

C. Oxygen content of plasma would be three times normal

Which of these statements about class-2 MHC molecules is false? a. They are found on the surface of B lymphocytes b. They are found on the surface of macrophages c. They are required for B cell activation by a foreign antigen d. They are needed for interaction of help and killer T cells e. They are presented together with foreign antigens by macrophages

C. They are required for B cell activation by a foreign antigen

Which of these would be most affected by a decrease in the affinity of hemoglobin for oxygen? a. Arterial Po2 b. Arterial percent oxyhemoglobin saturation c. Venous oxyhemoglobin saturation d. Arterial Pco2

C. Venous oxyhemoglobin saturation

Define: Humoral/Antibody-mediated Immunity

Can be far from the victim

Explain why cancer cells are believed to be dedifferentiated, and describe some of the clinical applications of this concept.

Cancer cells have been believe to be dedifferentiated (can change into less specialized cells found in the embryo). The production of two antigens (that are released during dedifferentiation process) by cancerous cells plays a vital role in diagnostic testing of cancer. Two test based on this process are the carcinoembryonic antigen tests and alpha-fetoprotein antigen test.

The hypoxic ventilatory response occurs when low arterial PO2 stimulates the

Carotid bodies

Define: Autoreactive T Cells

Cells that attack self-antigens. Usually occurs if mutations happen in lymphocytes or if cells that are in particular organs are never exposed to the immune system.

Define: Pathogen-Associated Molecular Patterns (PAMPs)

Cells that distinguish "self" from "nonself".

Define: Endogenous pyrogen

Chemical that sets the body temperature higher and is produced as a cytokine by leukocytes.

Killer T lymphocytes can be activated to destroy a victim cell ONLY if the cell presents antigens to them in association of?

Class-1 MHC

What mechanisms stop lymphocytes from attacking the self-antigens?

Clonal deletion and clonal anergy

Define: Classic Pathway

Complement System that is part of the nonspecific defense system where activity is triggered by binding of antibodies (IgG and IgM) to antigens of the invading cells membrane.

Define: Alternative Pathway

Complement System that is part of the nonspecific defense system where activity is triggered by polysaccharides on bacterial membranes. More rapid and efficient.

Fever

Component of nonspecific immunity. A process that (to a certain point) helps kill of bacterial infection. Regulated by the hypothalamus. Endogenous pyrogens (chemical produced as a cytokine) sets our body temperature higher. This process induces sleepiness and a fall in plasma iron concentration

Active Immunity may be produced by

Contracting a disease and receiving a vaccine

Define the term cytokines, state the origin of cytokine molecules, and describe their different functions.

Cytokines are the polypeptides that are secreted from the T lymphocytes and some other types of cells such as macrophages. These are signaling molecules that help in inflammation, regulation and mediating immunity. Functions: - Inducing the activation and proliferation of T lymphocytes - Stimulating proliferation of mast cells and bone marrow stem cells. - Stimulating the activation and proliferation of B and T lymphocytes. - Promoting differentiation of eosinophil and inducing activation of cytotoxic T cells. - Promoting the production of antibodies (IgE mostly). - Stimulating proliferation and differentiation of macrophages, monocytes, eosinphil and neutrophils.

Define: Lymphokines

Cytokines specific to lymphocytes. Many stimulate B cell or Cytotoxic T cell activity.

Which of these occur(s) during hypoxemia? a. Increased ventilation b. Increased production of 2,3-DPG c. Increased production of erythropoietin d. All of these

D. All of these

If the transpulmonary pressure equals zero a. a pneumothorax has probably occurred b. the lungs cannot inflate c. elastic recoil causes the lungs to collapse d. all of these apply

D. All of these apply

Which of these statements about the Fab portion of antibodies is true? a. It binds to antigens b. Its amino acid sequences are variable c. It consists of both H and L chains d. All of these are true

D. All true

Which of these statements about gamma interferon is false? a. It is a polypeptide autocrine regulator b. It can be produced in response to viral infections c. It stimulates the immune system to attack infected cells and tumors d. It is produced by almost all cells in the body

D. It is produced by almost all cells in the body

Which of these statements about complement proteins C3a and C5a is false? a. They are released during the complement fixation process b. They stimulate chemotaxis of phagocytic cells c. They promote the activity of phagocytic cells d. They produce pores in the victim cell membrane

D. Produce pores in the victim cell membrane

Which of these statements about T lymphocytes is false? a. Some T cells promote the activity of B cells b. Some T cells suppress the activity of B cells c. Some T cells secrete interferon d. Some T cells produce antibodies

D. Some T cells produce antibodies

If a person with normal lung function were to hyperventilate for several seconds, there would be a significant

Decrease in the arteries

Complement System: Proteins

Designated C1 through C9. Are present in inactive state within plasma and other bodily fluids. Become activated by attachment of antibodies to antigens. C1: Serves as a recognition protein. C4, C2, and C3 (in this order): Serve as activators C5-C9: Attack by attaching to a cell membrane and destroying it.

During a secondary immune response, a. antibodies are made quickly and in great amounts b. antibody production lasts longer than in a primary response c. antibodies of the IgG class are produced d. lymphocyte clones are believed to develop e. all of these apply

E. All apply

The affinity of hemoglobin for oxygen is decreased under conditions of a. acidosis b. fever c. anemia d. acclimatization to a high altitude e. all of these

E. All of these

Describe complement fixation, and explain the roles of complement fragments that do not become fixed.

Essential process that occurs during a antigen-antibody reaction that helps complete the attachment of complement proteins to the cell membrane in order to destroy the pathogenic cell(s). Certain complement fragments the form during the complement process that don't get fixed, but remain in the surrounding fluid instead. Their roles include: - Opsonization that helps in facilitating phagocytosis - Chemotaxis by attracting the phagocytic cells towards the site where complement activation occurs. - Stimulating the basophils and mast cells to release histamine - increasing blood flow to the site of infection.

Function: B cells

Exposure to the specific antigen activates a this cell and causes it to undergo multiple cell divisions. Where some can become memory or plasma cells. Combat bacterial and some viral infections. They secrete antibodies into blood and lymph so they can be far from the victim (meaning they undergo humoral immunity or also known as antibody-mediated immunity).

True or False: The binding of antibodies to antigens destroys the pathogen.

False - the labels target for attack by phagocytic cells and stimulates opsonization.

IgD

Function as antigen receptors on lymphocyte surface prior to immunization; other functions unknown.

IgM

Function as antigen receptors on lymphocyte surface prior to immunization; secreted during primary response

Barriers to entry: High Acidity in Stomach

Gastric juice has strong acidity (pH 1-2) that helps kill many microorganisms before they can invade the body. This kills the majority of microorganisms/pathogens.

Define: Major Histocompatibility Complex (MHC)

Group of genes that code for the proteins of histocompatibility antigens. Many versions of each gene are possible, so most people have different combinations. An organ transplant requires an ____ match. MHC genes produce two classes of cell surface molecules: class 1 and class 2.

The chemoreceptors in the medulla are directly stimulated by

H+ in brain interstitial fluid derived from blood CO2

Define: Antigen-presenting cells

Help T cells bind to antigens Ex: dendritic cells and macrophages

Define: Complement System

Helps integrate innate and adaptive immune responses. Consists of a group of plasma proteins that become activated when antibodies bond with antigens.

What do mast cells secrete?

Histamine

Define the term histocompatibility antigens and explain the importance of Class-1 and Class-2 MHC molecules in the function of T cells.

Histocompatibility antigen refers to any located on the membrane surface of blood cells or tissues that can trigger immune response. These antigens are coded by a group of genes known as Major Histocompatibility Complex (MHC). Class-1 MHC Molecules: Associated with antigens and activate cytotoxic T lymphocytes that attack the vector cells and kill them. Class-2 MHC Molecules: Associated with certain antigens that allow the activation of helper T lymphocytes.

Define: Human Leukocyte Antigens (HLAs)

Histocompatibility antigens in humans like our white blood cells.

Define: Cytotoxic (Killer) T Cells

Identified by their surface molecule called CD8. Function to destroy body cells that harbor foreign molecules. Undergoes cell-mediated destruction and secretes perforins (to create large pore in cell) and granzymes (to trigger apoptosis in cell).

Mast cell secretion during an immediate hypersensitivity reaction is stimulated when antigens combine with

IgE antibodies

Distinguish between immediate and delayed hypersensitivity.

Immediate: B lymphocytes are involved, onset of symptoms occurs within several minutes after exposure, IgE antibodies act on the antigen, produces allergic condition including asthma, high fever, etc., and can be treated with adrenergic and antihistamine drugs. Delayed: T lymphocytes are involved, symptoms occurs within 1-3 days after exposure, provides cell-mediated immunity, produces contact dermatitis, and can only be treated by corticosteroids.

What drugs will effectively treat the immediate and delayed hypersensitivity allergy reactions?

Immediate: Antihistamines because of the secretion of histamine. Delayed: Corticosteroids are the ONLY drugs that can effectively treat this. Delayed secretes lymphokines not histamines, so taking antihistamines has little effect.

Define: Passive Immunity

Immune protection that can be produced by the transfer of antibodies to a a recipient. Can be from a human or animal donor. Provides temporary protection: from mother to fetus, from mother to child (breast milk), artificially via immunization (snake anti-venom) If lymphocytes do begin attacking cells,

Define: Immediate Hypersensitivity

Immune response to an allergen that can cause symptoms of rhinitis, conjunctivitis, allergic asthma, atopic dermatitis, and food allergies.

Define the term immunological surveillance, and identify the cells involved in this function.

Immunological Surveillance is a theory that suggest the immune system has a role in fighting against cancer along with its ability to recognize and kill pathogens that invade into the body. The production of immunosuppressive molecules by tumor cells that include transforming factor beta (TGFB) and FAS ligand. T lymphocytes producing IL-10 and TGFB have been identified in suppression of the immune responses to tumor cells as well.

Define: Helper T Cells

Improve ability of B lymphocytes to become plasma cells and enhance ability of cytotoxic T cells to kill targets. Secrete of lymphokines. Identified by surface molecule CD4.

When does the immune system develop immunological tolerance for self-antigens?

In the fetal period

Explain the possible relationship between stress and susceptibility to cancer.

Increased risk of cancer due to stress can be explained due to the increased secretion of corticosteroids that suppresses the function of the immune system.

Define: Secondary Response

Individual will likely not get sick. Later exposure to the same infection results in maximum antibody production in less than 2 hours. Antibody production is more rapid.

Define: Lysis

Influx of water into the cell

Define: Regulatory (Suppressor) T Cells

Inhibit response of B lymphocytes and cytotoxic T lymphocytes. Individuals with genetic deficiencies in this cells production may develop autoimmune diseases and allergies.

What do alpha and beta interferons do?

Inhibit the ability for viruses to replicate and form new viruses. Almost all cells in the body produce these in response to microbial infection. These polypeptides act as messengers that protect other cells in the vicinity from viral infection.

Distinguish between innate and adaptive immunity

Innate Immunity: Inherited from the parents (pass from one generation to the next), nonspecific (no specific memory associated), antibodies are NOT produced, acts by providing barriers that prevents the entry of pathogens in body. Adaptive Immunity: Acquired during the exposure to different pathogens and through vaccinations after birth, specific (memory associated), acts by production of specific antibodies against pathogens, primary and secondary immune responses are produced via T- and B-lymphocytes to kill the pathogen.

Clonal Deletion

Lymphocytes are destroyed via apoptosis

Define: B cells

Lymphocytes that come directly from bone marrow to seed other organs (not the thymus).

What do macrophages secrete?

Lysosomal enzymes

Helper T lymphocytes can ONLY be activated by antigens presented to them in association with what?

MHC-2 molecules

What cell aids the activation of T lymphocytes by antigens?

Macrophages

Define: Class 1 MHC

Made by all cells except RBCs. This subclass of MHC molecules and foreign antigens are presented together to activate cytotoxic T cells.

Define: Class 2 MHC

Made by antigen-presenting cells (dendritic cells and macrophages) and B cells. This subclass of MHC molecules and foreign antigens are presented together to helper T lymphocytes.

IgA

Main antibody type in external secretions, such as saliva and mother's milk

IgG

Main form of antibodies in circulation; production increased after immunization; secreted during secondary response.

Describe the events that occur during a local inflammation.

Major events that occur: - Binding of the antigens present on the bacterial cell surface to the antibodies surface - activating the complement system. - Neutrophils and macrophages start phagocytosis after activation of complement system. - Histamine is released from mast cells along with other inflammatory inducers. - Inflamed site is invaded by extravasation of leukocytes

Results: Immune Complex Diseases

May result from infections from bacteria, viruses, or parasites: Hepatitis B results in free complexes that cause damage to arteries due to inflammation. Also could result from complexes formed by self antigens and autoantibodies Rheumatoid arthritis and lupus If this is prolonged or spread to other organs it usually leads to prolonged inflammation.

Bicarbonate concentration of the blood would be decreased during

Metabolic Acidosis

Define: Antigens

Molecules that stimulate the production of specific antibodies and combine specifically with the antibodies produced. Are large molecules that have several antigenic determinant sites.

What cells are included in the grouping of the mononuclear phagocyte system?

Monocytes (in the blood), macrophages (derived from monocytes), dendritic cells (located in the connective tissues).

Define: Chemotaxis

Movement toward chemical attractants (or chemokines).

Define: Cell-mediated Immunity

Must be in close proximity to the victim cell in order to destroy it

Process: Phagocytosis in Tissues

Neutrophils and monocytes squeeze through gaps in venule walls to enter tissue via extravasation (also called diapedesis).

Define: Dendritic cells

Originates in the marrow and migrates to most tissues (especially where pathogens might enter the body). Engulf protein antigens, partially digest them, and display polypeptide fragments on surface for T cell to "see". These secrete cytokines to attract lymphocytes. Associated with histocompatibility antigens

Define: Allergies

Particular types of abnormal immune responses to antigens called allergens. Two major forms of allergy: (1) Immediate Hypersensitivity and (2) Delayed Hypersensitivity.

Describe passive immunity and give examples of how it may occur naturally and how it may be conferred by artificial means.

Passive immunity is immunity provided by transferring specific antibodies to the host from a donor (human or animal). Can be conferred by artificial means through immunization to individuals that have extreme exposure to some viral infections like the venom of a snake, rabies, hepatitis (B or C), or tetanus. There is an antitoxin that contains antiserum (serum possessing antibodies) which is injected into the body of host providing short-term passive immunity.

What do Killer T cells secrete?

Perforins

Define: Organ-Specific Phagocytes

Phagocytes located in liver, spleen, lymph nodes, lungs, and brain. These are embryonically and functionally related to macrophages and can be considered part of mononuclear phagocyte system.

Define: Fixed phagocytes

Phagocytes that are immobile in the walls of the liver, spleen, lymph nodes, lungs, and brain.

List the phagocytic cells found in blood and lymph, and indicate which organs contain fixed phagocytes.

Phagocytic cells found in the blood are neutrophils and monocytes. Tissue macrophages are found in the lymph, bone marrow, spleen, and other tissues. Fixed phagocytes are types of phagocytes that are fixed in the sinusoids of certain organs. These phagocytic cells are found in the liver (Kupffer cells), lymph nodes, and spleen. These cells prevent the organs from invading pathogens including debris and chemicals through phagocytosis.

Barriers to entry: Epithelial Membranes

Physical barrier that blocks entry. Secrete a variety of antimicrobial peptides.

Define: Phagocytosis

Plays a large role in both specific and nonspecific immunity. A form of endocytosis where pathogen becomes engulfed by pseudopods. Vacuole containing the pathogen fuses with a lysosome and the pathogen is digested. Involves phagocytic cells.

Examples: Immunoassays

Pregnancy tests, blood type determination, strep tests

Describe the actions of interferons.

Produce non-specific, short-acting resistance to viral infections. Alpha and Beta interferon respond to microbial infections where they inhibit viral assembly and replication by using polypeptides as messengers to protect the other cells that are in the vicinity of the infection. Gamma interferons are secreted and play a role of immunological defense against infection and cancer.

Define: Autoimmune Diseases

Produced by failure of immune cells to tolerate "self"-antigens. Resulting in autoreactive T lymphocytes and autoantibodies are produced, causing inflammation and organ damage.

Define: Plasma cells

Protein factories that produce ~2,000 antibodies per second.

What is the only cell you can get DNA from?

Red Blood Cells (RBCs)

Define: Cancer

Refers to malignant tumors. A Result from altered expression of oncogenes, tumor suppressor genes, and genes that code for microRNA

Define: Natural killer cells

Related to lymphocytes distinct from T cells and part of innate immune system without the ability to recognize specific antigens. Can recognize malignant cells and cells infected with a virus, but must be activated by pro-inflammatory cytokines from dendritic cells. Kill similarly to cytotoxic t cells. Cytokines released by this cell activate both innate and adaptive immune cells

IgE

Responsible for allergic symptoms in immediate hypersensitivity reactions

Define: T cells

Seed the thymus and become ____ lymphocytes. These then seed the blood, lymph nodes, and spleen.

Define: Innate (NonSpecific) Immunity

Serves as a "first line of defense" against pathogens. We are born with this.

Define: Haptens

Smaller, nonantigenic molecules that can become antigens when bound to other proteins. Useful for creating antigens for research and diagnosis.

Interleukin-1

Stimulates ACTH secretion

Interleukin-12

Stimulates formation of TH1 helper T lymphocytes

Interleukin-2

Stimulates proliferation

Define: Mast Cells

Store and release granules. Found in most tissues, especially concentrated in the skin, bronchioles, and intestinal mucosa. Identified by their content of heparin. Can secrete heparin, histamine, prostaglandins, leukotrienes, cytokines, and/or TNF-α.

Delayed hypersensitivity is mediated by

T cells

Define: Cell-mediated Destruction

T cells must touch the target victim.

Define: Immunoassays

Tests that use specific antibodies to identify specific antigens. Binding causes agglutination, which can be seen.

If the blood lacked red blood cells but the lungs were functioning normally

The arterial PO2 would be normal

Define: Immunological Tolerance

The immunological competence that is established by the ability to produce antibodies against non-self (foreign) antigens while tolerating "self"-antigens occurs. lIt is important to avoid attacking "self" cells.

Erythropoietin is produced by:

The kidneys

Clonal Anergy

The lymphocytes are prevented from becoming active. Regulatory T lymphocytes will likely do this.

The rhythmic control of breathing is produced by the activity of inspiratory and expiratory neurons in

The medulla oblongata

Define: Primary Response

The person gets sick. After infection, it takes 5−10 days before antibodies are detected in the blood.