Chapter 21 The Immune System Innate and Adaptive body Defenses
Phagocytosis steps
1)Adherence to pathogen or debris 2)Phagocyte forms pseudopods & Engulfment 3) Lysosomes fuses with the phagocytic vesicle (breaks it down) forming Phaglyosome 4) Toxic compounds and lysosomal enzymes destroy 5) Sometimes exocytosis of the vesicle removes indigestible & residual material
How does that adaptive immune system work?
- Amplifies inflammatory response (cascade reactions) -Responsible for most complement activation
Other inflammatory mediators besides histamine
- Kinins, prostaglandins (PGs), and complement • All cause vasodilation of local arterioles • All make capillaries leaky • Many attract leukocytes to area • Some have other inflammatory roles, such as triggering pain receptors, or prompting release of more inflammatory chemicals
Inflammation
- The inflammatory response is triggered whenever body tissues are injured Injuries can be due to trauma, intense heat, irritating chemicals or infections by microrganisms such as viruses, fungi or bacteria
Shortcoming
- must be primed by initial exposure to specific foreign substance - priming takes time
What are the benefits to moderate fevers?
-Causes liver and spleen to sequester iron & zinc that is needed by microorganisms to reproduce. -It increases metabolic rate, which increases rate to repair. (tissues that were destroyed
Helper T cells(part of adaptive system) help Phagocytosis by
-Docks with macrophage and activated B cells and T cells triggering macrophages to produce to lysomal enzymes by respiratory burp, which kills pathogens resistant to lysosomal enzymes by: -Releasing cell-killing free radical -Produces oxidizing chems(H2O2) -Increases pH & osmolarity of phagolysosome
What are adaptive defenses?
-Humoral immunity (B cells) -Cellular immunity (T cells)
Adaptive defense
-Humoral immunity (B cells) travels in fluid called humerus like lymph or plasma -Cellular immunity (T cells) attack effected cells
What are the 4 immune response characteristics that's sets adaptive apart from innate
-It involves lymphocytes B & T cells (not involved with innate defense) -It is specific (recognized and identifies target) -It is systemic (not restricted to the initial infection site) -It has "memory" (after initial exposure it recognizes and mounts stronger attacks on previously seen antigens)
Surface barriers are skin and mucous membranes, along with their secretions
-Physical barrier to most microorganism -Keratin is resistant to weak acids and bases, bacterial enzyme and toxins -Mucosae provide mechanical barriers
What are the benefits of inflammation
-Prevents spread of damaging agents -Disposes of cell debris and pathogens -Alerts adaptive immune system -Sets the stage for repair -starts the reaction to replace the cells if they are destroyed
What is part of the innate defenses?
-Surface barriers (skin and mucous membranes) -Internal defenses ( phagocytes, Natural killer cells, inflammation, antimicrobial proteins and fever)
What are the benefits of edema?
-Surge of fluid in tissue sweeps foreign material into lymphatic vessels for processing in lymph nodes -Delivers clotting proteins and complement to area (clotting factors from fibrin mesh that acts as scaffold for repair) Mesh also isolates injured area so invaders cannot spread (repair the wall)
Vasodilation and increased vascular permeability
-Vasodilation causes hyperemia—congestion with blood—which leads to redness and heat -Increased capillary permeability causes exudate(fluid containing clotting factors and antibodies)to leak into tissue
proliferation (mitotic division) and differentiation
-activated lymphocytes proliferate (multiply) and then differentiate into effector cells and memory cells -memory cells and effector T cells circulate continuously in the blood and lymph and throughout the secondary lymphoid organs
innate and adaptive defenses are intertwined
-both release and recognize many of the same defensive molecule -Innate defenses do have specific pathways for certain substance -Innate responses realize proteins that alert cells of adaptive system foreign molecules -cascade of reactions
Natural killer cells attack
-cells that lack "self" cell-surface receptors -kill by inducing apoptosis in cancer cells and virus-infected cells before the adaptive immune system has been activated -secrete chemicals that enhance inflammatory response
What are the two means of cellular immunity
-directly -indirectly
Vasodilation and increased vascular permeability results in
-local selling (edema) -Swelling also pushes on nerve endings, resulting in pain -Pain can also result from release of toxins from bacteria or released prostaglandins and kinins
C3b
-opsonization -coats bacteria to enhance phagocytosis by making the macrophages recognize they need to be destroyed
antigenic determinants
-parts of antigen that antibodies or lymphocyte receptors bind to -specific part of an antigen that are immunogenic and bind to free antibodies or activates lymphocytes -most naturally occurring antigens have numerous antigenic determinants that mobilize several different lymphocytes (different types of antibodies can bind) -They form different kinds of antibodies
3 Important Aspects of the Adaptive Immune Response
-the adaptive defense recognize & destroy the specific antigen-initiate the response -immune response is a synthetic response, not limited to initial infection site -immune system has memory- can respond faster 2nd time around
How do interferons work?
-viral infected cells are activated to secrete IFNs (small proteins) -IFNs enter neighboring cells that have not been infected -neighboring cells produce antiviral proteins that block viral reproduction -used in hep B and C, genital warts and MS
What is the most abundant antibody group
IgG
Seeding secondary lymphoid organs and circulation
Immunocompetent B and T cells not yet exposed to antigen called naive Exported from primary lymphoid organs (bone marrow and thymus) to "seed" secondary lymphoid organs (lymph nodes, spleen, etc.) Increases chance of encounter with antigen
What are the two functional properties of antigens?
Immunogenicity or reactivity
leukocytosis
Injured cells release chemicals. (leukocytosis-inducing factors) abnormal increase of white blood cells (inflammation). Neutrophils to blood from bone marrow increase 4 to 5 fold in few hours.
What are the two intrinsic systems if the immune system?
Innate (nonspecific) defense system Adaptive (specific) defense system
What protein can be released by infected cells to help protect cells that have not yet been infected?
Interferon is a small protein that can stimulate nearby healthy cells to defend themselves against viral infection.
How many types of antimicrobial proteins are there?
Interferons and complement proteins
What innate internal defenses work by interfering with viral replication?
Interferons are antimicrobial proteins that interfere with viral replication. They are produced by a virus-infected cell. Although the infected cell will die, it sends out interferons that protect the neighboring cells from the
Interferon is a small protein that can stimulate nearby healthy cells to defend themselves against viral infection.
Interferons encourage the production of antiviral proteins. These antiviral proteins are coded in the cell's DNA. These proteins can degrade viral RNA and interfere with viral protein synthesis.
What is the area lymphocytes proliferate (multiply) and differentiate(become effector T cells or memory cells)?
Lymph node
What is the area seeded by immunocompetent B and T cells
Lymph node
What is the areas where antigens challenged and clonal selection are most likely to occur?
Lymph node
Antigen encounter and activation happens in the
Lymph node when a lymphocyte's antigen receptors bind its antigen, that lymphocyte can be activated
T lymphocytes (T cells)
Lymphocyte that originates in bone marrow matures in the thymus and acts directly against antigens in cell-mediated immune responses. Attacks Intracelluar paths like virus infected and cancer. Effector cells are Cytoxic T cells, Helper Cells, Regulartor cells Memory cell formation Immune response cellular
Which leukocytes are sometimes referred to as "housekeeping" phagocytes because of their role in clearing (cleaning up) cell debris?
Macrophages
What type of immune system cell performs the most phagocytosis in the body?
Macrophages, or "big eaters," perform most of the phagocytic activity in the body: they ingest bacteria, cellular debris, and aging blood cells, among others.
Which of the following is NOT a property of mucous membranes? A)Mucous membranes produce defensins that can damage pathogen cell membranes. B)Mucus contains macrophages that attack invading pathogens. C)Mucin in mucus allows it to trap pathogens. D)Mucus contains lysozymes that destroy bacteria.
Mucus contains macrophages that attack invading pathogens. Mucus itself does not typically contain macrophages.
Which of the following is NOT a characteristic of Natural Killer (NK) cells? A)NK cells recognize abnormal or cancer cells by a specific antigen on their cell membrane. B) NK cells attack infected or cancerous cells. C) NK cells induce the target cell to undergo "apoptosis" (cell suicide). D)NK cells attack transplanted organs.
NK cells recognize abnormal or cancer cells by a specific antigen on their cell membrane. . NK cells do not recognize abnormal or cancer cells by a specific antigen on their cell membrane. NK cells to do not have specific antigen receptors - like T cells do. NK cells look for the absence of normally occurring "self" proteins on infected or cancerous cells.
what can kill cancer cells & virus -infected cells before adaptive immune system is activated?
Natural killer cells -nonphahocytes that price blood & lymph
Naturally acquired vs. Artificially acquired
Naturally- formed in response to actual bacterial or viral infection Artificially acquired- formed in response to vaccine of dead pathogens
Phagocytes- 2 type &what do they do?
Neutrophils and & macrophages -confront microorganisms that breach the external barriers -Phagocytes must be able to adhere to counter pathogens coat with compliment protein-opsonins Neutro & macro engulf pathogen and digest the contents with lysosomal enzymes and when they can't release chemical lethal to pathogens (respiratory burst)
Diapedesis
Neutrophils flattens and squeeze between the endothelial cells of the capillary walls
Phagocycte mobilization
Neutrophils flood to the area first; then macrophages follow -If inflammation is due to pathogens, complement is activated; adaptive immunity element arrive
What are some physical factors that will help get rid of bacteria?
vomiting and diarrhea
free macrophages (wandering)
wander through tissue spaces, example: areolar macrophages
Natural Killer (NK)
Nonphagocytic, large granular lymphocytes that police blood and lymph -Can Kill Cancer and Virus-infected cells before adaptive immune system is activated and they secrete chemicals that enhance the inflammatory response
With what does our immune system coat pathogens to facilitate their capture and accelerate phagocytosis?
Opsonins are needed to provide a gripping point on some cells that have capsules or other defenses against adherence by phagocytes.
How do WBC recognize it's not our cell?
Or carbohydrate signature
What characterizes the chemotaxis phase of phagocyte mobilization?
Phagocytes move up concentration gradients of attractive chemicals (chemotactic agents) released from damaged tissue and inflammatory cells.
What are some of the cells that are involved in the second line of defense?
Phagocytes: Neutrophils , macrophages
Dendrites
Phagocytize pathogens that enter tissues, then enters lymphatics to present antigens to T cells in lymph node. - -act as mobile sentinel and can be located in tissues and epidermis. -very efficient -presents part of the molecule to MHC cell and activate complement system and inflammatory response and stimulate more production of WBC -happens in lymphocytes or spleen -presenting on MHC -happens inside of spleen or lymph nodes -takes it to secondary lymphatic organs (lymph nodes or spleen )
Immune system major function
Provides resistance to disease. To protect our body against micro organisms
How do pyrogens work?
Pyrogens act on body thermostat in hypothalamus, raising body temp. They activate prostaglandins to reset the hypothalamic temperature-regulating center in the brain to a higher level
Which of the following should produce naturally acquired, active immunity? A)getting a flu vaccine B)injections of antibody produced by a goat C)drinking breast milk D)recovering from the chicken pox
Recovering from the chicken pox Exposure to an antigen and the subsequent immune response provides naturally acquired active immunity
Tuberculosis Bacilli (TB)
Resists digestion by macrophages and will remain alive and can form tumor like growths called granulomas. Area of infected macrophages surrounded by uninfected macrophages and outer capsule that protects itself and will reproduce. Bacteria may remain inactive forever or if persons immunity decreases, may become activated and cause disease
Haptens (Incomplete Antigens)
Small molecules (peptides, nucleotides, and hormones), not immunogenic by themselves, are immunogenic when attached to body proteins, cause the immune system to mount a harmful attack. Ex: Poison ivy, animal dander, detergents, and cosmetics.
Interferons (IFNs)
Small proteins released by infected cells to help protect cells that have not been infected yet -interferes with virus reproduction -helps protect heathy cells
Phagocytosis and Tuberculosis
Some pathogens are not killed with acidified lysosomal enzymes. Ex: TB
When you inject a serum, a vaccine, in to healthy animals what happened?
Start an immune reaction by injecting an antigen, that facilitates the production of the B cells which then mature into plasma cells to release antibodies that will react with that first antigen
Self-Antigens: MHC Proteins
your bodies antigens that are not antigenic to you, only others and are identified as "self" by MHC (major histocompatibility complex) proteins on the surface of cells unique to you -example blood -coded by genes of major histocompability complex (MHC) -cell surface proteins that identify (glycoproteins) -contain groove that can hold each individual antigen or foreign antigen
complement system consist of
~20-30 blood proteins that circulate in blood in inactive form. The proteins include C1-C9, factors B, D, and P and regulatory proteins
basic antibody structure
T- or Y-shaped antibody monomer of four looping polypeptide chains linked by disulfide bonds Two identical heavy (H) chains with hinge region at "middles" Two identical light (L) chains Variable (V) regions at one end of each arm combine to form two identical antigen-binding sites
secondary immune response
The adaptive immune response provoked by a second exposure to an antigen. It differs from the primary response by starting sooner and building more quickly. memory cells facilitate a faster, more efficient response -sensitized memory cells provide immunological memory respond within hours and peak 2 to 3 days -antibodies bind with greater strength -Antibodies level can remain high for weeks to months
Which of the innate defense mechanisms can lyse bacteria and mark cells for phagocytosis?
The complement proteins can lyse microorganisms using the MAC (membrane attack complex) system to form pores, mark cells for phagocytosis (opsonization), and promote inflammation.
What part of the antibody's structure determines its class?
The constant region, which includes parts of each heavy and light chain, is identical to other molecules in its class but differs between classes.
What happens if surface barriers are breached?
The internal second line of defense will be triggered. This line of defense protects deeper tissues
How do phagocytes recognize foreign cells or bacteria?
The phagocytes recognize molecules on pathogens not normally found on body cells. They use mannose and Toll-like receptors to bind to the molecules found on pathogens.
clonal selection
The process by which an antigen selectively binds to and activates only those lymphocytes bearing receptors specific for the antigen. The selected lymphocytes proliferate and differentiate into a clone of effector cells and a clone of memory cells specific for the stimulating antigen.
When tissue is damaged, what activated the arterioles to dilate?
The release of inflammatory chemicals (histamine, complement, kinins, prostaglandins)
Which is a part of the innate immune defenses? A)T cells B)B cells C)antibodies D)skin
The skin is the first innate barrier that works to prevent entry of any pathogens into the body.
In certain classes of antibody, the monomeric versions join to form dimers. What portions of the molecules adhere to each other to form these dimers?
The stem region of one monomer may bond to the stem region of one or two other antibody molecules. Return to Assignment
How is the adaptive third line of defense able to target specific pathogens?
The third line of defense responds to antigens on the pathogen. All foreign invaders of the body present antigens that can activate the adaptive immune response. The adaptive immune response can then produce antibodies that bind to the antigens to help identify, disable, and destroy the pathogens.
Why are antibodies specific for certain pathogens?
Their antigen binding site is complementary to the shape of an antigen. So they only bind to one type of pathogen
Adaptive (specific) defense system
Third line of defense attacks particular foreign substances (takes longer to react than innate) most complex takes time to attack specific antigens
What is the area where T cells become Immunocompetent?
Thymus
What is one example of a bacteria that is not digested by phagocytes.
Tuberculosis bacilli
Which of the following best illustrates artificially acquired active humoral immunity? A)vaccines B)antibodies received in breast milk C)infection D)antivenoms
Vaccines induce the patient to produce antibodies, so the resulting immunity is active, but it is artificially acquired since it was injected during a medical procedure.
Which of the following is NOT one of the effects produced by the release of inflammatory chemicals? A)vasoconstriction B)attraction of neutrophils C)redness D)increased access of clotting chemicals
Vasoconstriction Inflammatory chemicals dilate, rather than constrict, local arterioles and make local capillaries more permeable.
Neutralization
When antibodies block all binding sites on a virus
When can haptens induce an immune response?
When attached to an immunogenic substance called a carrier protein from our own body Hapten + Protein -causes immune response to mount attach that is harmful to person because it attacks self-proteins to happen
phagosome
When the cell picks up a foreign body pulls it inside to a membrane-line vesicle
C3 complement protein
Where the three pathways converge. Splits and initiates a common terminal pathway that enhances inflammation, promotes phagocytosis and can cause lysis
What can act as opsonins on bacteria, thus enhancing phagocytosis?
Yes, both antibodies and complement proteins can act as opsonins on bacteria
Complement
a group of blood borne proteins, which, when activated enhance the inflammatory and immune responses and may lead to cell lysis
Adaptive immune system (third line of defense)
a specific defensive system that eliminates almost any pathogen or abnormal cell in body -will also attack our own abodes abnormal cells -takes time
Reactivity
ability to react with activated lymphocytes and antibodies released by immunogenic reactions
Fever
abnormally high body temperature; systemic response to invading microorganisms -leukocytes and macrophages exposed to foreign substances secrete pyrogens
Acid Mantle (acid)
acidity of skin and some mucous secretions inhibits the growth
What is the name of the unique area (specific region) that a lymphocyte recognizes and binds to?
an antigenic determinant(epitope), is the specific part of an antigen that the antibody or lymphocyte antigenic determinant receptor binds to.
antigens generate
antibodies
artificially acquired active immunity
antibodies are made due to exposure to a vaccine (dead or attenuated pathogen) -provide antigenic determinate that are immunogenic and reactive -spare us symptoms of primary response
Which of the following best describes humoral immunity? A)antibodies being released in the body fluids B)edema and formation of exudate C)mobilization of phagocytes D)activation of T cells in the lymphatic fluid
antibodies being released in the body fluids Humoral immunity refers to the presence of specific antibodies in the body fluids
Defensins
antimicrobial peptides that inhibit microbial growth
Second line of defense (innate immunity)
antimicrobial proteins, phagocytes, fever, natural killer cells and other cells (inhibit the spread of invaders) Inflammation most important mechanism
antimicrobial proteins enhance the innate defenses by
attacking microorganisms directly or hindering their ability to reproduce with Interferons and Complement
What is the area where B cells become Immunocompetent?
bone marrow
Where do B cells mature?
bone marrow
primary immune response (humoral immunity)
cell proliferation and differential upon exposure to antigen for first time. Lag period 3 to 6 days Peak levels reached at 10 days -Antibodies levels then decline ones antigens are gone.
When you increase temperature you increase
cellular activity of repair inflamed tissue
Inflammatory chemical release
chemicals are released into ExtraCellular Fluid by injured tissues, immune cells, or blood proteins Ex: histamine realized by Mast cells(WBC that travel inside connective tissue, outside of blood vessels) is key to inflammatory chemical
abscess
collagen fibers are laid down, walling off sac of pus these may need to be surgically removed
classical pathway of complement activation
complement binds to an antibody that is bound to a foreign substance.
Antigens can be ____ or ____
complete or incomplete
Innate (nonspecific) defense system
constitutes first and second lines of defense
Pus
creamy yellow mixture of dead neutrophils, tissue/cells, and living/dead pathogens
Chemicals like bacterial toxins that poison cells are described as being
cytotoxic
Cancer cells would be attacked by which of the following cells?
cytotoxic T cells attack cancer cells, since they are part of cell-mediated immunity.
What is the strongest APC
dendritic cell
What are the 3 antigen presenting cells (APCs)?
dendritic cells, macrophages, B cells
lysis
destruction
Macrophages
develop from monocytes and are chief phagocytic cells; most robust phagocytic cell * VERY BIG CELL
naturally acquired active immunity
develops after exposure to antigens in environment
What characterizes flattening of neutrophils to squeeze between the endothelial cells of the capillary walls?
diapedesis The flattening of neutrophils and subsequent movement through the vessel wall is in response to cell adhesion molecules on endothelial cells.
Cellular Immunity
direct attack of microorganisms by lymphocytes and has living cells rather than free proteins as its protective factor Indirect by releasing chemicals inside/outside that enhance inflammatory response or activating other lymphocytes or macrophages to kill cell
Anti-presenting cells (APCs)
engulfs antigens and then present fragments of them, like signal flag on their own surfaces where T cells can recognize them. Naive T cells can only be activated by antigens that are presented to them on MHC protein by APCs
Antimicrobial proteins
enhance innate defense by attacking microorganisms directly or hindering microorganisms ability to reproduce Interferons & complement proteins
activated macrophages
enhanced to increase their phagocytic capabilities
C3a
enhances inflammation: Stimulates histamine release, increases blood vessel permeability, attacks phagocytes by chemotaxis
Another way to destroy bacteria is by
fever
What are the two types of macrophages?
fixed and free
MAC (membrane attack complex)
forms and stabilizes a hole in the membrane that allows a massive influx of water, lysing (destroying) the target cell
Inflammation results from
from a release of inflammatory chemicals from damaged cells that cause vasodilation, & increase capillary permeability, which allows for more fluid containing clotting factors and antibodies to enter the tissues
Immune system is a __________ ________ rather than organ system
functional system
What determines the foreign substance the immune system will recognize?
genes of DNA, not antigens we encounter, determine which specific substances our innate system will be able to recognize and resist.
The respiratory system also has modification to stop pathogens like
hair, cilia, mucous
What are the 4 signs of inflammation?
heat, pain, redness, swelling -sometimes fifth, impairment of function is seen if movement or use of area is hampered -causes vasodilation which Increase capillary permeability which allows fluid w/ clotting factors to enter the tissue
Skin
highly keratinized epithelial membrane, and mucous membrane represent a physical barrier to most micro organized and enzymes and toxins low pH
What inflammatory chemicals is/are released by mast cells?
histamine is one of the products produced by mast cells to moderate inflammation. It is also released by basophils, which are similar to mast cells but reside in the blood.
What type of immunity can be transferred by bodily fluids from one person to another, thus conferring immunity to the recipient?
humoral immunity involves antibodies that can be transferred from one person to another.
Glycoproteins are important for
immune recognition
Antibodies facilitate
immune response
Naive cells
immunocompetent (mature) B & T cells that have never encountered antigen
Immuno means
immunology or physical immunity
Chemotaxis
inflammatory chemicals act as chemical trails that promote positive chemotaxis of neutrophils and other WBC toward injured area
interferon and complement are antimicrobial proteins that enhance
innate defenses by attacking microorganisms
Tears and mucus membranes would be a part of which defense system?
innate external defenses (surface barriers) are the first line of defense and include tears, mucus membranes, and the skin.
lectin pathway of complement activation
lectin binds to specific sugars on microorganisms surface
What are some other chemicals that are part of you innate defenses?
lipids in sebum and dermicidin in sweat are toxic to some bacteria
B lymphocytes (B cells)
lymphocytes which originate and mature in the bone marrow and that are involved in the production of antibodies that attack extracellular pathogens (bacteria, fungi, parasites and some virus.) Memory Cell formation and and effector cells are plasma Immune response humoral
Enzymes
lysozyme of saliva, respiratory mucus, and lacrimal fluid kills many microorganism enzymes in stomach kill many microorganism
What is the most important reason you should not try draining an abscess by pressing on it?
may spread infection to deeper tissue
Clone cells that do not become plasma cells become
memory cells
More Edema =
more fluid= more WBC
Neutrophils
most abundant phagocytes, but die fighting; become phagocytic on exposure to infectious material develop from stem cells in the bone marrow
What are the two types of active humoral immunity
naturally acquired and artificially acquired
Neutr means
neutral or neutrophil
Active humoral immunity
occurs when B cells encounter antigens and produce specific antibodies against them
passive humoral immunity
occurs when ready-made antibodies are introduced into body -B cells are not challenged by antigens -Immunological memory does not occur -protection ends when antibodies degrade
The antivenom used to treat a venomous snake bite is an antibody produced in an animal such as a horse. Suppose these antibodies are injected into a patient who has been bitten by a venomous snake. How would you classify the resulting humoral immunity?
passive immunity, artificially acquired The immunity to venom (usually short lived--the protection ends once the antibodies are naturally degraded by the body) is passive because the patient did not produce the antibodies, and it is artificially acquired since it was injected during a medical procedure.
phagolysosome
pathogen-containing vesicles associated with a lysosome within the phagocyte When a cell eats, and the "food" joins with a lysosome prior to digestion
Innate system uses the first and/or second lines of defense to stop attacks by
pathogens (disease-causing microorganisms) ex: virus bacteria fungi
Phagocytes must be able adhere to a pathogen before it can engulf it. How does it do this?
pathogens are coated with complement proteins called opsonins
fixed macrophages
permanent residents in tissues and organs; ex: stellate macrophages (liver) and microglia(brain)
Margination
phagocytes cling to the inner walls (margins) of the capillaries and post capillary venues. It allows for the neutrophils to bind to endothelial cells tightly, creating initial foothold.
What cells make antibodies?
plasma B cells - the plasma B cells make antibodies in response to specific antigens.
Toxic means
poison
inflammatory response
prevents injurious agents from spreading to adjacent tissues, disposes of pathogens and dead tissue cells promotes tissue repair, released inflammatory chemicals attract phagocytes (and other immune cells) to the area
B cells think
production of antibody
mucous membranes (wet layer)
protective chemical of the epithelial tissue include acid to inhibit bacterial growth, enzyme (lysine) to destroy microbes, mycin-sticky traps defense- defend
skin and mucous membranes produce
protective chemicals that inhibit or destroy microorganisms Acids, enzymes, mucin and defensins
MHC or Major Histocompatibility complex
proteins are responsible for displaying antigens to immune cells.
antibodies (immunoglobulins Igs)
proteins secreted by B cells -make up gamma globulin portion of blood -capable of binding specifically with antigen detected by B cells -Grouped 1 of 5 Ig classes
What causes the most reaction (immunogenicity)
proteins. Amino aids have the least
Many second-line cells have pattens recognition receptors that
recognize and bind tight to structures on microbes, disarming them before they do harm
What is the area the B and T cells form?
red bone marrow
What are the steps in the phagocyte mobilization?
1. Leukocytosis 2. Margination 3. Diapedesis 4. Chemotaxis
What are the 3 pathways of complement activation?
1. classical pathway 2. alternative pathway 3. lectin pathway
How many sites on this antibody molecule have potential to bind to a non-self molecule?
2- Each antigen-binding site has potential to attach to a non-self molecule.
effector cells
short-lived cells that take effect immediately, fighting the infection
Phagocytes
A type of white blood cell(neutrophil and macrophages) that ingests invading microbes that have breached the external barriers
What is the first line of defense in the innate defense system?
skin(dry layer) and mucous membranes (wet layer)
What are some of the protective chemicals that are produced from your skin and mucous membranes as part of your innate defenses.
Acid, enzymes, mucin, defense and other chemicals
alternative pathway of complement activation
Activated spontaneously. lack of inhibitors on microorganisms surface allows to proceed
Humoral immunity (antibody mediated immunity)
specific immunity produced by lymphocytes (B cells) that produce antibodies that circulate freely in body fluids like blood or lymph (humoral). They will them bond primarily to extracellular targets like bacteria, bacterial toxins and free viruses inactivating them and marking them for destruction by phagocytes or complement
Mucin
sticky mucous that line digestive respiratory system straps microrganisms ex: traps and ejects microorganisms that are stuck in the respiratory system
complete antigens
substances that can mobilize the adaptive defenses, with both immunogenicity and reactivity functional properties
Innate defenses
surface barriers and internal defenses surface: skin and mucous Internal: phagocytes, NKC, Inflammation, Antimicrobial proteins Fever
Immunogenicity
the ability to stimulate specific lymphocytes to proliferate (multiply) -able to mount immune response
non-self antigens
Any substance capable of promoting the immune system and provoking an immune response
What are the 3 crucial types of cells in the adaptive immune system?
B-Cells, T-Cells and antigen presenting cells
Which letter represents the formation of a phagolysosome resulting from the fusion of a lysosome with the phagocytic vesicle?
C - The lysosome fuses with the phagocytic vesicle, forming a phagolysosome
C3a and C3b are the products of
C3 being spit
If a virus attacks a cell, which type of immunity would be activated?
Cell-mediated immunity(cellular immunity) involves an intracellular pathogen such as a virus. (already infected cells)
What are the two branches of the adaptive system?
Cellular and humoral immunity
Phagocytotic cells such as macrophages identify a variety of enemies by recognizing markers unique to pathogens. They would be classified as which type of defense system?
the macrophage recognizes many molecules found on pathogens that are not present on normal body cells.
Pyrogens
Chemicals that are releases when leukocytes and macrophages are exposed to foreign substances like Bacteria and viruses, they elevate body temperature
What is/are the specific target(s) of interferons?
the membrane receptors on healthy cells Interferon binds to membrane receptors in healthy cells and triggers a response inside the cell that leads to the production of chemicals that interfere with virus manufacture.
classical vs. alternative pathway (complement system)
Classical have antibody tat will cover bacteria Alternative -has cascade (c3-c9) that will help to form channel in membrane (bacteria)
Phagocytic
the process by which cells surround and digest certain particles
innate defense system is they system that is
there and what is immediate ready for you
Complement provides a major mechanism for
Destroying foreign substances in the body Activation enhances inflammation and also directly destroys bacteria Nonspecific defensive mechanism that Enhances both INNATE and ADAPTIVE DEFENSIVES
What happens if temp is to high
Destruction of health tissue
When do neutrophils enter the blood from the red bone marrow in response to leukocytosis-inducing factors?
During leukocytosis, neutrophils enter the blood from the red bone marrow in response to leukocytosis-inducing factors from damaged cells.
What specific sign of inflammation is the result of exudate in the tissue spaces?
Edema is caused when release of fluids from blood vessels exceeds their uptake. Not only is blood flow increased to inflamed areas, but capillaries are made more permeable to fluid, resulting in loss of fluid from the blood and tissue swelling
Where do T cells mature?
thymus
Antigens
Foreign material that invades the body and can mobilize the adaptive defenses or immune response -targets of all adaptive immune responses -Most are large, complex molecules not normally found in body -can be complete or happen(incomplete)
hist means
tissue
Where do T and B cells develop?
From stem cells in the red bone marrow
Antibody groups
GMADE IgM, IgG, IgA, IgD, IgE
Antigen Receptor Diversity
Genes, not antigens, determine which foreign substances the immune system will recognize varsity of immune cell receptors are result of acquired genetic knowledge -different gene codes for up to a billion different types of lymphocyte antigen receptors
phago means
to eat or feeding