Chapter 12: Immunology

steps of inflammatory response

1) defense by tissue macrophages-they attack foreigners immediately and secrete cytokines 2) vasodilation to increase blood flow via histamine release from mast cells=more WBC and proteins for defense 3) localized edema: more protein= increase in ISF = increase in ISF colloid pressure and increase capillary blood pressure = fluid out of capillary = ultrafiltration and decrease reabsorption = edema(swelling)= red and heat from increase in blood flow 4) increase capillary permeability by increasing pores so plasma proteins can leave 5)thromboplastin->fibrinogen->fibrin(final clotting factor) that forms ISF clots and blocks injured area from healthy area to prevent spread of infection 6) emigration of leukocytes -neutrophils 1st-> then monocytes (8-12 hours later) which mature into macrophages (8-12 hours) and once neutrophils leave the blood, they never go back 1. Damaged tissues release histamines, increasing blood flow to the area. 2. Histamines cause capillaries to leak, releasing phagocytes and clotting factors into the wound. 3. Phagocytes engulf bacteria, dead cells, and cellular debris. 4. Platelets move out of the capillary to seal the wounded area.

Internal defense

1) phagocytes:macrophages and WBC (neutrophils and monocytes) 2) inflammatory reactions 3) fever 4) interferons 5) complement system 6) natural killer cells SECOND LINE OF DEFENSE (Innate immunity)

Monocytes

*A type of white blood cell that transforms into macrophages, extends pseudopods, and engulfs huge numbers of microbes over a long period of time *An agranular leukocyte that is able to migrate into tissues and transform into a macrophage.

NLRS

-"Nod like Receptors" -produce the induction of pro-inflammatory cytokines by creating inflammasomes -Production of IL-1 (activates T cells) -located in cytoplasm -detect peptidoglycan, cell damage, and flagellin -distinguish intracellular PAMPS like bits of bacterial cell wall engulfed by phagocyte or parasites.

IL-2

-Secreted by all T cells -Stimulates growth of helper, cytotoxic, and regulatory T cells, and NK cells. -IL-1 enhances B and T cell clones and stimulates IL-2 by activating helper T cells

IgD

Immature antibody that is embedded in the membrane of B cells and other immune cells dealing with phagocytosis (primarily B cells). Function unclear

cell-mediated immunity

type of immunity produced by T cells that attack infected or abnormal body cells -B cells recognize free-existing foreign invaders like bacteria and their toxins and a few viruses and attack via antibodies -t cells recognize and destroy body cells gone awry

antibody-mediated immunity or humoral immunity

Immunity that results from the presence of antibodies in blood and lymph.

Antigen-binding fragments

unique for each antibody, so each antibody can interact only with an antigen that specifically matches it, much like a lock and key.

IL-12

Induces differentiation of T cells into Th1 cells. Activates NK cells. -drives naive T cell to become TH1 cell but IL-4 favors naive T cell to T helper 2

endogenous pyrogen (EP)

Induces fever. Causes prostaglandins to release from hypothalamus to increase body temperature = fight infection

Primary response

Initial response to a specific antigen. During a primary response, T and B lymphocytes are activated and specific antibodies and memory cells to the antigen produced. During initial contact with antigen, the antibody response is delayed for several days until plasma cells are formed and doesn't reach peak for a couple of weeks; mediated by IgM antibodies

External Defences and internal defences

Innate immunity has ___ and ____ defences _

IgM

Is the BCR for antigen attachment and made in early stage of plasma cell response. Immature form of antibody. Large and nonspecific antigen. It's the first antigen producer during infection bc it's large and nonspecific. Not good at triggering an immune response, there to accumulate bacteria and keep them all in one place

B lymphocytes (B cells)

Lymphocyte that matures in the bone marrow and secretes antibodies. Antibody-mediated immunity

T lymphocytes (T cells)

Lymphocyte that matures in the thymus and acts directly against antigens in cell-mediated immune responses. Punch lethal holes in victim cells

natural killer cells (NK cells)

Lymphocyte-like cell that nonspecifically lyse(rupture) and destroy virus-infected host and cancer cells

T cell helper 17

Make IL-17 = promote inflammation and are effector cells in development of inflammatory autoimmune diseases. Like attack on myelin in multiple sclerosis

Phagosome

vacuole merged with a lysosome and degrades.

Innate Lymphoid Cells (ILCs)

Mirror helper T cells that spur other immune cells into action. Always ready but less powerful than helper T

T cell receptor (TCR)

Molecule on the surface of a T cell that can bind to a specific antigen fragment in combination with an MHC molecule. -unique receptor and get them in thymus. T cell is activated by antigen when the surface of the cell has both an individuals identity (self antigen) and foreign antigen.

Neutrophils

Most abundant white blood cell., The most abundant type of white blood cell. Phagocytic and tend to self-destruct as they destroy foreign invaders, limiting their life span to a few days.

natural killer cells (NK cells)

Naturally occur that nonspecifically destroy infected cells and cancer cells to rupture them in first exposure. After exposure, cytotoxic T cells have maturation period before they can launch lethal assault. these have immediate defense on infected and cancer cells before cytotoxic T cells become functional. Antibodies made via NK cells

Bacteria

Nonnucleated, single-felled microorganisms equipped with machinery essential for survival and reproduction. Can cause tissue damage by releasing enzymes or toxins

Inflammation

Nonspecific defensive response of the body to tissue injury, including dilation of blood vessels. Neutrophils and macrophages play a major role

Viruses

Not self-sustaining, only have nucleic acids (DNA or RNA) enclosed by a protein coat and can't metabolize or reproduce unless they invade a host cell and take over that cells biochemical facilities for their own uses. These can take energy of host cell to make proteins needed for viral replication. -the body may destroy cell because it can't recognize it as a normal self-cell.

Perforin

One of the proteins released by cytotoxic T cells on contact with their target cells. It forms pores in the target cell membrane that contribute to cell killing.

Spleen

Organ near the stomach that produces, stores, and eliminates blood cells. Largest lymphoid tissue that clears blood

external defenses of innate immunity

Physical barriers: skin, mucus, nasal hair, cilia Chemical barriers: oil and sweat, stomach acid or low ph, earwax, lysoszome in tears and tissue fluid, vaginal bacteria producing low ph FIRST LINE OF DEFENSE (Innate immunity)

acute phase proteins

Plasma proteins made by the liver whose synthesis is rapidly increased in response to infection. They include mannose-binding lectin (MBL), C-reactive protein (CRP), and fibrinogen. -aid in inflammation and repair

IgG

Primary specific antibody. Takes 7-10 days to make. Specific to a particular antigen. Produced by memory cells from previous infections. -made and secreted when body is re-exposed to same antigen, makes most specific immune responses against bacterial invaders -act as opsonins to promote phagocytosis

Receptor editing

Process by which the T- or B-cell receptor sequence is altered after the initial recombination event, in order to reduce affinity for self antigens. -B cell escapes death by changing its antigen receptor to non self version so it won't target body tissues

Plasma cells

Produces antibodies that can combine with specific type of antigen that stimulates activation of plasma cell. B cell swells as RER expands and plasma cells make proteins to antibodies but plasma cells die in 5-7 days

Active immunity

Production of antibodies from exposure to antigen

T helper 2

Promote antibody mediated immunity (especially IGE) by B cells to rev up eosinophil activity

Interferon

Protein produced by cells in response to being infected by a virus; helps other cells resist the virus. Activation of RLR= trigger making of ___:an innate mechanism that defends against viral invasions by telling neighbors its infected so they resist virus.

RLRs

Recognize viral DNA or RNA in cytosol

CD4+CD25+ T cells

Regulatory T cell receptors

Eosinophils

Secrete chemicals that destroy parasitic worms and involved in allergic reactions

Granstein cells

Serve as antigen presenting cells and work in conjunction with other cells to fight foreign bodies as a part of the body's immune defense system. Brake on skin activated immune responses. Immune suppressor

clonal selection theory

States that the antigen selects which lymphocyte will undergo clonal expansion and produce more lymphocytes bearing the same type of receptor. -proposes that B cells are made in fetal development and can make an antibody against antigen without ever being exposed to it. All offspring of old B cell form identical cells (clones) to make the same antibody -B cells are inactive until they bind with antigen

T-independent antigens

Stimulate the B cell without the help of T cells Provoke a weak immune response, usually producing IgM No memory cells generated -stimulates production of antibody without the help of T cells Ex: B cells bind and activate T independent polysaccharides

Directly

T cells bind __\ with their targets.

Inside

T cells defend invaders ___ cells where antibodies and complement system can't reach them. T cells directly contact invader by Cell mediated immunity -T cells are clonal and antigen specific

Thymus

T cells mature in the __.

Helper T cells

T cells that help the immune system by increasing the activity of killer cells and stimulating the suppressor T cells. Don't directly participate in immune destruction of pathogens, they modulate other immune cells. -the master switch to fully power other cells. Most numerous (60-80%). Receptors are CD4+ cells

Cytotoxic T cells

T cells, often called killer cells because of their capability to kill invading organisms. Destroy host cells harboring anything foreign and bearing a foreign antigen, like body cells invaded by viruses, cancer cells with mutated proteins, and transplanted cells. T cell receptors are coreceptors CD8 and are inserted into plasma membrane as these cells pass through the thymus

Histamine

TNF stimulates the release of __ = vasodilation and increases capillary permeability

Secondary 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. It's is same antigen re-appears, the memory cells launch a faster and stronger and longer response; mediated by IgM Ex: vaccination

Self-tolerance

The normal situation whereby a person's immune system does not respond to constituents of the person's body. Prevents immune system from attacking own tissue

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. -only function is to recognize one particular antigen

Clonal deletion

The process of destroying B and T cells that react to self antigens. Destroyed in the thymus

hygiene hypothesis

The proposition that increasing allergies among children are the result of decreased exposure to microbes, such as those found in dirt. suggests that limiting exposure to pathogens may lower immune tolerance and the ability to cope with harmless antigens

CD8 T cells

The subset of T cells that express the CD8 co-receptor and recognize peptide antigens presented by MHC class I molecules. cytotoxic T cells.

Lymphocytes

The two types of white blood cells that are part of the body's immune system: B lymphocytes form in the bone marrow and release antibodies that fight bacterial infections; T lymphocytes form in the thymus and other lymphatic tissue and attack cancer cells, viruses, and foreign substances.

activating complement system

This involves receptors on tail of antibody to activate C1-> form MAC—> attack membrane of foreign cell that has the antigen and the system enhances inflammation -all IgG antibodies activate the same complement system; all IgE activate same complement system

antibody-mediated immunity

This type of immunity is mediated by B cells and primarily protects against BACTERIAL invaders

cell-mediated immunity

This type of immunity is mediated by T cells and protects primarily against VIRUS infected host cells

FoxP3

Transcriptional repressor protein of regulatory T cells. turns T cells into T refs and let's them quiet other immune cells(NK, B,T, dendritic cells)

classical complement pathway

Triggered by antibodies (activated by the presence of antibody bound to microorganism). -an adaptive immune response that destroys cells by forming membrane attack complexes that punch holes in victim cells - usually dependent on antigen-antibody interactions - this is part of acquired immunity and not as fast as the other pathways - produces cleavage products that participate in opsonization, chemotaxis, and the membrane attack complex - can also be activated in response to some microbial products

TNF

Tumor necrosis factor Involved in the inflammatory process

DAMPs (damage-associated molecular patterns)

What endogenous molecules are produced or released from a damaged cell? -endogenous (like extracellular ATP released from trauma damaged cells) -aka alarmins

B cell

__ cell clones multiply into plasma or memory cells. Most multiply in plasma cells and have same binding sites as surface receptors and switch to produce igG antibodies that are secreted, not membrane bound. Short lived

Destruction of bacteria

__ of ___ is the main function of the inflammatory response

Bacteria and virus

___ and ___ are major targets of the immune system

Active immunity and passive immunity

___ and ___ immunity are part of acquired immunity and are third line of defense THIRD LINE OF DEFENSE

PAMPS and DAMPS

___ and ___ initiate innate immune response

Interferon

___ inhibit the multiplication of viruses in most cells. 3 related cytokines released from virus-infected cells and provides nonspecific resistance to viral infections by interfering with replication of viruses in other host cells

Macrophages

___ last longest but neutrophils die sooner

Glucocorticoids

___ suppress inflammatory response and decreases antibody production and destroy lymphocytes. Treat allergic reactions, asthma, but it decreases the ability to fight infection -Humira inhibits TNF

IL-1, IL-6, TNF(tumor necrosis factor)

___, __, and ___ all defend against infection/ injury and make you "not feel well" when you have an infection

B cell receptor (BCR)

a cell-surface antibody that acts as an antigen receptor on a B cell Molecule on the surface of a B cell that binds to a specific antigen.

Complement system

a defense mechanism with 20 different proteins brought into play nonspecifically and activated in 2 ways: 1)exposure to specific carb chains on microorganisms not found on human cells, a nonspecific innate response called alternate complement pathway 2)exposure to antibodies

Autoimmune disease

a disease in which the immune system attacks the organism's own cells Ex: Type 1 diabetes, multiple sclerosis

Memory cells

a long-lived lymphocyte capable of responding to a particular antigen on its reintroduction, long after the exposure that prompted its production. -small portion of B cells are this and they don't participate in active attack against antigen, they expand this clone so if person re-experiences antigen, these cells are ready for a more immediate action than their original clone was

Bradykinin

a powerful vasodilator that increases capillary permeability and constricts smooth muscle. Activates nearby pain receptors and makes soreness and dilated vessels and kinins enhance more neutrophils to join

Antigen

a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies. - a large molecule that triggers specific immune response against itself. An antibody generator. Foreign proteins are the most common ___ because of big size and complexity A protein that, when introduced in the blood, triggers the production of an antibody

Virulence

ability to produce disease. The power of the pathogen

IL-5

activates eosinophils

interferon gamma

activates macrophages and other immune cells. Released from NK cells-> binds to receptor on macrophage-> makes it go nuts-> super phagocytes

Granulocyte-macrophage colony-stimulating factor

acts on the one marrow to increase production of WBCs. Makes and released neutrophils and monocytes-macrophages

Selectins

allow cells to adhere to carbohydrates on the surfaces of other cells and are most commonly used in the immune system. -a type of cell adhesion molecule (CAM) protudes from vessel and causes WBCs in blood to slow down so neutrophils and monocytes can check for activating factors("SOS signals")

ADCC (antibody-dependent cell-mediated cytotoxicity)

antibodies attached to target cell cause destruction by macrophages, eosinophils, and NK cells In _____, the NK cell which expresses CD16 (an Fc receptor) binds to the Fc portion of an antibody, such as IgG, which has bound to the surface of a pathogen-infected target cell. The NK cell can secrete cytokines as well as induce apoptosis via perforins and granzymes.

T cell receptor (TCR)

antigen receptor on the surface of a T cell Molecule on the surface of a T cell that can bind to a specific antigen fragment in combination with an MHC molecule.

Dendritic cells

antigen-presenting cells in the skin

Dendritic cells

antigen-presenting cells in the skin. Macrophages and these are specialized APCs that act as a guard in almost every tissue. Lots in skin and mucosal linings in lungs and digestive tract because microbes enter here lots. They leave tissue home-> travel in lymph system to lymph nodes-> cluster and activate T cells

C-reactive protein (CRP)

blood test used to measure the level of inflammation in the body; may indicate conditions that lead to cardiovascular disease. Marker of inflammation and serves as nonspecific opsonin that binds to bacteria

T helper 1

cells responsible for vascular changes, recruitment and activation of inflammatory cells in type IV hypersensitivity -rally cell mediated cytotoxic T cell response for infections with intracellular microbes like viruses

Antigen-presenting cells (APCs)

cells such as B cells, macrophages, and dendritic cells that can present exogenous antigens to naive or memory T cells, activating them -they introduce T cells to antigens and T cells only respond to antigens by these!!!!!!!! cells that process protein antigens and present them on their surface in a form that can be recognized by lymphocytes (white blood cells)

Peter's patches

clusters of lymphatic tissue around small intestine to monitor digestive system

membrane attack complex (MAC)

complement system components assembled to form pores in membranes of invading cells. Embeds itself in surface membrane of nearby microorganism creating channel through the membrane ->makes the hole-> leaky membrane-> water into cell and swells and bursts. -MAC can muse microbe in 30 seconds!!

Regulatory T cells

control the T-cell response. Have cd4 and cd25, component of a receptor for IL-2 to promote T reg function. Known as cd4+CD25+ T cells

T follicular helper cells (Tfh)

effector CD4 T cell present in lymphoid follicles that cooperates with B cells to help antibody production -interact with B cells in lymph node follicles to secrete antibodies and promote memory B cell differation

Granzymes

enzymes that attack proteins of target cells and initiates apoptosis. Cell self destructs and virus released is directly destroyed in ECF by phagocytes, neutralizing antibodies, and complement system -cytotoxic T cell is unharmed but can kill other infected host cells and inferno and NK help in viral infections

MHC 1

expressed on almost all nucleated cells, not expressed on RBC, Binds to TCR and CD8; examples = HLA-A, B, C -suicide signal. Infected cells process proteins from infectious organism, present them on cell surface bound to MHC class I to tell immune system cells "hey I'm infected, kill me" -only ones without MHC are neurons and cardiac muscle cells bc they don't go through mitosis so we don't want them to die

Lactoferrin

found in milk, saliva, and mucus. Binds iron A protein found in secretory fluids and neutrophils that inhibits microbial growth via iron chelation. -tightly binds iron so iron can't be used by bacteria because bacteria multiply with iron

Langerhan cells

from bone marrow, provide immunity. Serve as antigen presenting cells

transplant rejection

identification of transplanted tissue as foreign by the recipient's immune system, which responds by attacking the tissue

immunodeficiency

immune system with decreased or compromised response to disease-causing organisms. Lack B and T cells and you live in a bubble

adaptive immunity

immunity or resistance to a specific pathogen; slower to respond, has memory component the ability to recognize and remember specific antigens and mount an attack on them -relies on SPECIFIC immune responses selectively targeted against a particular foreign material to which the body has already been exposed and can prepare to attack the enemy. Takes more time

Chemokines

induce migration of leukocytes A chemical secreted by blood vessel endothelium and monocytes during an immune response to attract phagocytes to an area -cytokines that act on chemotaxins are known as __. -chemotaxins bind with protein receptors to increase calcium entry=contraction= crawling

IL-4

induces differentiation into th2 cells; promotes growth of b cells; enhances class switching to igE and igG -promotes making of IgE antibodies for defense against parasitic worms

NSAIDS

medication that exerts analgesic and anti-inflammatory actions. Ex: aspirin and ibuprofen and glucocorticoids (cortisol) -aspirin decreases histamine release to decrease swelling, pain, and redness and fever by inhibiting prostaglandins

Chemotaxins

molecules that attract phagocytes to a site of infection

perforin and granzymes

natural killer cells use _____ and _____ to induce apoptosis of virally-infected cells and tumor cells.

Neutralization

occurs when a pathogen can no longer infect a host because it is bound to an antibody. Antibodies combine with bacterial toxins and antibodies bind to virus surface antigen so the virus can't enter cell and cause damage

innate immune system

part of the immune system designed to rapidly dispose of pathogens in a nonspecific manner. a collection of nonspecific barriers and cellular responses that serve as an inborn first and second line of defense against pathogens -nonspecific immune responses that come into play immediately on exposure to a threatening agent. They're built in and are the first line of defense. Everyone is born with the same innate immune response -neutrophils and monocytes (macrophages) important in innate defense

Diapedesis

passage of blood cells (especially white blood cells) through intact capillary walls and into the surrounding tissue. WBC crawls to injured area (NEUTROPHILS ARRIVE FIRST)

Clonal anergy

process whereby B cells that react to soluble antigens in bone marrow are made nonfunctional -clones that escape destruction in thymus are rendered nonfunctional in peripheral by anergy. Only on APC surface but antigen and co-signs are never present for self antigens because they aren't handled by cosignal bearing APCS. 1st signal turns off T cell= __ ___ and T cell is inscribed.

Interferon alpha and beta

produced by virally infected cells to prevent infection of adjacent cells. Tell neighboring cells it's infected and sets up an antiviral state -prevents spread of viral replication. Shuts down protein synthesis machinery in infected cells because viruses invade cells and take over protein machinery so they can make copies of themselves

Interleukins

proteins (cytokines) that stimulate the growth of B and T lymphocytes -between leukocytes

Skin-associated lymphoid tissue (SALT)

recognizes microbes that may slip past the physical barrier. Protective -in digestive tract: saliva and acid protect, acidic urine and vaginal secretions in urogenital system.

Kallikrein

secreted by neutrophils to change plasma proteins into kinins which help in inflammation

Inflammation, interferon, NK cells, complement system

4 innate defenses include:

malignant tumor

A cancerous tumor that is invasive enough to impair the functions of one or more organs. Multiply and form more tumors. Spread cancer (metastasis)

Basophils

A circulating leukocyte that produces histamine. And heparin and are involved in allergic reactions

Gut-associated lymphoid tissue (GALT)

A collection of lymphoid tissue in the gastrointestinal tract that includes the appendix, the lacteals, and Peyer's patches. Attack invaders before they spread too far

Major Histocompatibility Complex (MHC)

A family of genes that encode a large set of cell surface proteins called MHC molecules. Class I and class II MHC molecules function in antigen presentation to T cells. Foreign MHC molecules on transplanted tissue can trigger T cell responses that may lead to rejection of the transplant

Pus

A fluid created by infection. Contains white blood cells, bacteria, and dead cells. -collection of phagocytic cells

active immunity

A form of acquired immunity in which the body produces its own antibodies against disease-causing antigens. In contact with antigen: 1)t cells:cytotoxic, helper, suppressor, and memory 2) B cells: plasma and memory 3)antigen presenting cells= macrophages, B cells and dendritic cells

Immunological ignorance

A form of self-tolerance in which reactive lymphocytes and their target antigen are both detectable within an individual, yet no autoimmune attack occurs. -antigen sequestering self molecule hidden from immune system because it never comes into contact with ECF

complement system

A group of blood proteins that bind non-specifically to the surface proteins of foreign cells (such as bacteria), ultimately leading to the destruction of the foreign cell - part of the innate immunity. -inactive plasma proteins that destroy foreign cells by attacking their plasma membrane

AIDS

A serious (often fatal) disease of the immune system transmitted through blood products especially by sexual contact or contaminated needles. Acquired immunodeficiency syndrome caused by HIV that invaded CD4+ T cells and decreases the immune response

Integrins

A transmembrane protein that interconnects the extracellular matrix and the cytoskeleton. Ex: cytokines cause WBC to stick to endothelial lining by interacting with this CAM __.

Inflammasomes

Activated NLRS triggers formation of multi protein complexes called ___ which bring a strong inflammatory response complementing the actions triggered by activated TLRS

Antibody and cell mediated immunity

Adaptive immune responses include __ and ___ immunity

B and T cells

Adaptive immunity customized its defenses for specific pathogens and is mediated by __ and ___ cells. Whereas innate immunity is fast and nonselective when responding to foreigners and limits spread of infection

Benign tumor

An abnormal mass of cells that remains at its original site in the body. Slow growing and doesn't infiltrate surrounding tissue

Itself

An antigen induces an immune response against ___.

macrophage inhibition factor

Another cytokine released from helper T cells that keeps macrophages in the region by inhibiting their outward movement. Angry macrophages are gathered and have a more powerful destruction. Defend against bacteria that causes tuberculosis

Tail portion

Antibodies are Y shaped and classified based on properties of their __ ___ because their Y shape tells whether it's an IgG, IgA, or IgE. -variable region that will change in structure based on antigen.

Passive immunity

Antibodies artificially produced outside directly injected into the body -no contact with pathogen

Bacterial

Antibody mediated immunity protects primarily against ____ invaders

immune complex disease

Antibody mediated. Web of antibody and viruses together (immune complex), -too many antigen-antibody complexes and damages normal cells. Arteritis Glomerulonephritis: IC complex deposited Choroiditis

Thymosin

stimulates the maturation of lymphocytes into T cells of the immune system. Hormone that maintains T cell lineage. and secretion from this decreases with age (30 or 40)

PAMPs (pathogen-associated molecular patterns)

structures found on foreign microbes but NOT on self cells. Exogenous (like carbs found in bacterial cell wall, but not in human cells). Stimulates innate immune response

Antigen

Antigens amplify the innate immune responses to promote ___ destruction. -neutralization, aggulutination, activate complement system, stimulate NK

T-dependent antigens

Antigens that can stimulate antibody production only with help from T helper cells. Protein antigens, need helper T, most are T-dep.

Regulatory B cells

suppress helper T cells to prevent autoimmunity. Suppress harmful immune responses instead of turning into plasma cells to make antibodies (1-2%) of B cells

immunity

the ability of an organism to resist a particular infection or toxin by the action of specific antibodies or sensitized white blood cells. -1st like of defense is epithelial later on the outer surface of the body (skin)

Extravasion

Anytime something extra leaves tube(circulatory system) . Occurs via diapedesis. Diapedesis is when a WBC will send two pseudopods to either side to squeeze between the gap in the cell and neutrophils leave the site of circulatory system and enter the site of infection

ECF

B cells defend enemies in the ___. They secrete antibodies to attack at long distances

Bone marrow

B cells mature in the __.

Innate response activator (IRA)

B cells, part of adaptive immune system that recognize bacteria by TLRS and overlaps with innate system (make cytokines). Act slowly to make antibodies

Opsonins

Bind with microbes and enhance phagocytosis -tag particles to be ingested

Kinins

Blood proteins that help inflammation, blood pressure control, coagulation, and pain They reinforce inflammation

hybrid natural killer T cells and natural killer T cells(NKT)

Both NK and cytotoxic T cell characteristics (only 0.2%). Suppress autoimmunity and tumor rejection. Nervous system defense: antibodies target viruses in ECF and neurons

alternate complement pathway

By exposure to particular carbohydrate chains present on the surfaces of microorganisms but not found on human cells, a nonspecific innate immune response.

Antiviral effect

Cell warning other cells that a virus is attacking with interferons. Triggers virus-blocking enzymes and make enzymes that can break down RNA and inhibit protein synthesis = no viral replication. Enzymes activated by virus. Fast response.

Virus

Cell-mediated immunity protects primarily against __ infected host cells

Plasma cells

Cells that develop from B cells and produce antibodies.

Agglutination

Clumping of microorganisms or blood cells, typically due to an antigen-antibody interaction. Multiple antibody molecules cross link antigen molecules into chains of antigen-antibody complexes so foreign cells clump up Ex: differences in FC distinguish different subclasses. IgG tail region binds with phagocytic cells which serve as opsonin to enhance phagocytosis. IgE antibodies attach to mast cells and basophils and released histamine

Opsonins

Coating proteins that promote phagocytosis: IgG and C3b. They make cells more attractive for pathogens. (Like putting powder sugar on doughnut) -make bacteria more susceptible to phagocytosis "prepare for eating" -most important of these are antibodies and an activated protein of complement system. One part of this binds to surface of enemy and other portion binds to receptor sites specific for it on phagocytic cells membrane

Chemotaxins

Components of the activated complement system that attract leukocytes from the circulation to help fight infections. -WBC know where to go because they're attracted to these. They're chemical mediators released at the site of damage

Constant factor (FC)

Contains binding sites for particular mediators of antibody-independent activities which vary. This region binds to antigen and it changes because you have different antigens

Margination

the sticking of phagocytes to blood vessels in response to cytokines at the site of inflammation Ex: neutrophils and monocytes stick to inner endothelial lining of capillary I'm injured tissue

lymphoid tissues and organs

the tissues and organs that work with the immune system to defend the body, including the thymus, bone marrow, lymph nodes, spleen, tonsils, adenoids, and other structures

Passive immunity

Direct transfer of antibodies formed by another person, transfer of IgG class occurs from mom to fetus across placenta. Moms milk gives baby IgA

Lysosome

Engulfed bacteria fuses with ___-> protein fragments -> bind to MHC molecule —> MHC transports antigen to cell surface to T lymphocytes (presents cell) -> alerts immune system -> T cells only attack intracellular invader and must have self-antigen -> T cell binds with APC-> secretes cytokines to activate clonal expansion and acts as paracrine on B cells, cytotoxic T cells, and NK cells

Anti cancer effects

Enhances actions of cell-killing cells (natural killer cells) and cytotoxic T cells-attack and destroy virus-infected cells and cancer cells. Interferon slows cell division and decreases tumor growth

Interferon

Family of proteins produced by the T-cell whose specialty is fighting viruses by slowing or stopping their multiplication. They nonspecifically defend against viral infection

IgA

Found in the secretions of the digestive tract, respiratory tract, urogential system, milk, and tears. Found in saliva, nasal secretions -nonspecific to prevent infection and coat it. Tells macrophages to get rid of it before it causes a problem

MHC class II

Found on helper T cell. Recognized antigen presenting receptors on antigen presenting cells. Found on cells that recognize antigen on antigen presenting cells -helper CD4+ T cells, restricted to surface of few types of immune cells. Helper T cells bind with foreign antigen only when it's on immune cells with helper T cell and directly interacts with macrophages, dendritic cells, and B cells. -B cells don't phagocytize, they undergo receptor mediated endocytosis

Class I MHC molecules

Found on the surface of all nucleated body cells, T cells bind only with foreign antigens with self antigens. Deadly T cells can link with cancerous cells because class ___ have a foreign appearance. All cells can be invaded or be cancerous so they all display class ___ __ glycoproteins = cytotoxic T cells attack any invaded host cell or cancer cell. Normal cell bodies are safe from attack because they don't have foreign antigen

1) defends against pathogens 2) removes worn out cells and tissue damaged by trauma or disease 3) identifies and destroys abnormal cancer cells that have originated in the body (immune surveillance)

Functions of immune system

Major Histocompatibility Complex (MHC)

Group of genes that code for proteins found on the surfaces of cells that help the immune system recognize foreign substances. Has foreign and self antigens -wait a few days and then the activated T cells attack. Have a memory pool and primary and secondary responses. Primary response is initiated by lymphoid tissue. T cells die by suicide in a few days

Chemotaxins

Helper T cells can function as ___ to lure more neutrophils and macrophages to infection

Interleukins

Helper T cells secrete ___ (IL-4, IL-5, IL-6) serve as B cell growth factor which contributed to B cell function with IL-1 secreted by macrophages -antibody secretion decreases without helper T cells

CD4 cells

Helper T cells, turn response on, most numerous

IgE

Helps protect against parasitic worms and is an antibody mediator for common allergic responses (hives, fever). Lines respiratory tract

Mast

Histamine can be released from ___ cells to augment inflammation

Cytokines

Hormone-like chemicals facilitating communication between brain and immune system. They're protein signaling molecules that regulate immune responses and are secreted by WBCs. Ex: helper T cells, macrophages, monocytes, neutrophils, and fibroblasts all secrete this. -unlike antibodies they don't interact directly with the antigen, they activate other immune cells to thward off invader

Stress

IL-1 can turn on ___ response by activating neuro and endo systems. Stress suppresses immune system Ex: stimulates T cells in spleen -> ACH-> cytokine secretion decreases-> decrease inflammation. Ex: immune system to nervous system: immune secretions act on the brain to produce fever

B and T

IL-1 enhances proliferation of __ and __ lymphocytes = antibody production and cell mediated immunity

Iron

IL-1,IL-6, and TNF decrease the plasma concentration of iron by changing ___ metabolism in liver so less iron can bind with bacteria = less bacterial multiplication

Toll-like receptors (TLRs)

transmembrane protein of immune cells that recognizes pathogens and activates an immune response directed against those pathogens -on host cells that recognize and attach to pathogen-associated molecular patterns (PAMPs) -TLR engulf enemy and secrete a chemical from phagocytic cell = inflammation. -located at cell surface and can recognize pathogens in the ECF