Term
| what is a hypersensitivity reaction |
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Definition
| An exaggerated response or a response that causes tissues damage |
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Term
| Too little response results in |
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Definition
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Term
| Loss of tolerance to "self" tissue is called |
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Definition
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Term
| antigens that stimulate a destructive immune response |
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Definition
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Term
| which type of immuglobin typically involved in allergic response |
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Definition
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Term
| four types of hypersensitivites |
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Definition
| Immediate IgE mediated, cytotoxic, immune complex mediated, delayed cell mediated |
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Term
| Type 1: Immediate IgE mediated hypersensitivity, what is…the type of cell that is responsible for the reaction, |
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Definition
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Term
| • the type of antibody involved, |
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Definition
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Term
| • the host cells that are most likely to be involved, and |
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Definition
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Term
| • the time required for the reaction to occur after exposure to the antigen. |
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Definition
|
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Term
| example of this type of reaction |
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Definition
| hives, hay fever, asthma, anaphylactic shock |
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Term
| what do people with Type I hypersensitivities have |
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Definition
| IgE antibodies attached to mast cells throughout their bodies |
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Term
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Definition
| process in which at least 2 cell-bound IgE molecules react with antigens, and the IgE molecules cross-link, causes mast cell to release histamine and other inflammatory mediators |
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Term
| what do histamine and other inflammatory mediators cause |
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Definition
| capillary dilation, smooth muscle contraction, mucus secretion - direct cause of hives, hay fever, asthma, a. shock |
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Term
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Definition
| allergens absorbed in intestinal tract, carried to skin, & bind IgE carried by mast cells, mast cells degranulate releasing inflammatory mediators |
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Term
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Definition
| allergic rhinitis - an airborn antigen is inhaled, causes itching teary eyes, sneezing, same mechanism as hives, blocked by antihistamine |
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Term
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Definition
| immediate respiratory allergy - allergen reacting with IgE sensitized mast cells causes degranulation, releasing into lower respiratory tract causes bronchial tube spasms (eosinophils also contribute) |
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Term
| which mediators responsible for asthma, vs hay fever |
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Definition
| leukotriens, prostaglandins (lipids), vs histamine for hay fever |
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Term
| is antihistamine effective in treating asthma |
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Definition
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Term
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Definition
| rare serious form of IgE mediated allergy - antigens enter the blood stream and spread throughout the body, inflammatory mediators released extensively causes drop in blood pressure, can be fatal within minutes |
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Term
| what controls anaphylaxis |
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Definition
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Term
| immunotherapy treatment - desensitization does what |
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Definition
| diluted allergen injected to stimulate IgG production which binds antigen instead of IgE, activated regulatory T cells also play a role through release of cytokines that suppress IgE response |
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Term
| type II - cytotoxic hypersensitivity, what is…the type of cell that is responsible for the reaction, |
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Definition
| B cells, antibodies react with molecules on the surface of a cell and trigger its destruction |
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Term
| how are cells destroyed in Type II |
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Definition
| by the complement system or antibody-dependent cellular cytotoxicity |
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Term
| • the type of antibody involved, |
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Definition
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Term
| • the host cells that are most likely to be involved, and |
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Definition
|
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Term
| • the time required for the reaction to occur after exposure to the antigen. |
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Definition
|
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Term
| example of this type of reaction |
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Definition
| transfusion reaction, hemolytic disease of the newborn |
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Term
| what is a transfusion reaction |
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Definition
| when transfusion occurs and blood has different antigens than own, natural antibodies bind & results in agglutination (clumping) |
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Term
| which blood antigens are "natural" |
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Definition
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Term
| which antigen causes hemolytic disease of the newborn |
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Definition
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Term
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Definition
| Rh- means they do not have antibodies to RH |
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Term
| what is most common blood type of mother & father when hemolytic newborn disease |
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Definition
| Rh negative woman carrying Rh+ baby |
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Term
| what are steps in sensitization |
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Definition
| Rh- mother becomes sensitized to & produces antibodies to Rh+ cells, after exposure to babies blood (during birth)…with second baby her anti-RH IgG antibodies cross the placenta to baby |
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Term
| why not sensitized first time exposure |
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Definition
| IgM produced on first exposure, cannot cross placenta - |
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Term
| type III - immune complex mediated hypersensitivity, what is…the type of cell that is responsible for the reaction, |
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Definition
| IgG & IgM immune complexes, formed if slightly more antigen than antibody and smaller complexes formed, not completely eliminated - complexes lodge in blood vessel walls & elsewhere capillaries small/densely packed, B cell |
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Term
| htype III - immune complex mediated hypersensitivity, how are cells destroyed in Type III |
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Definition
| trigger blood clotting cascade & compliment system |
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Term
| • type III - immune complex mediated hypersensitivity, the type of antibody involved, |
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Definition
|
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Term
| • type III - immune complex mediated hypersensitivity, the host cells that are most likely to be involved, and |
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Definition
| blood vessels, skin, joints kidneys |
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Term
| •type III - immune complex mediated hypersensitivity, the time required for the reaction to occur after exposure to the antigen. |
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Definition
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Term
| example of this type of reaction |
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Definition
| serum sickness, farmers lung, disseminated intravascular coagulation |
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Term
| disseminated intravascular coagulation |
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Definition
| clots form in small blood vessels, leading to failure of vital organs |
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Term
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Definition
| localized immune complex reaction - if antigen injected to a previously immunized person, complex can form at the site of injection |
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Term
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Definition
| systemic immune complex disease caused by passive immunization - when antibodies introduced to human (from other animals) |
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Term
| type Iv- immune complex mediated hypersensitivity, what is…the type of cell that is responsible for the reaction |
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Definition
| due to antigen specific T cell responses, anywhere in body - helper T cells recognize antigens and release pro-inflammatory cytokines |
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Term
| • the type of antibody involved, |
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Definition
|
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Term
| • the host cells that are most likely to be involved, and |
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Definition
|
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Term
| • the time required for the reaction to occur after exposure to the antigen. |
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Definition
| peak 2-3 days after antigen exposure |
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Term
| example of this type of reaction |
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Definition
| tuburculin reaction, contact dermititis |
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Term
| sequence of events in type IV reaction - hypersensitivity - first exposure |
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Definition
| hapten from allergen combines with skin protein, dendritic cells present hapten:peptide complex to T cells, T cells activate & proliferate....next exposure -helper T cells activate macrophages, release inflammatory mediators, cytotoxic T cells destroy skin cells (presenting hapten:peptide), a rash appears after 24 hours |
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Term
| sequence of events in type IV reaction - hypersensitivity - second exposure |
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Definition
| .next exposure -helper T cells activate macrophages, release inflammatory mediators, cytotoxic T cells destroy skin cells (presenting hapten:peptide), a rash appears after 24 hours |
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Term
| rejection of transplanted tissue is a special case of what |
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Definition
| delayed-type cell mediated hypersensitivity |
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Term
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Definition
| tissue of donor and recipient are not genetically identical |
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Term
| what antigenic differences lead to rejection of grafts |
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Definition
| differences in major histocompatibility complexes (MHC's) |
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Term
| what cells cause tissue rejection |
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Definition
| cytotoxic T cells and Natural Killer (NK) cells |
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Term
| what is done to avoid rejection |
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Definition
| antigen incompatibilities minimized by using MHC tissue typing and ABO blood typing to match donor and recipient tissues |
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Term
| what must be done to avoid prevent graft rejection after, indefinitely |
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Definition
| immunosuppressant drugs - but make recipient more susceptible to infections and cancer (only limit T cells though) |
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Term
| what is an important transplant that saves lives with multiple myeloma and leukema |
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Definition
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Term
| what has to happen with bone marrow transplant |
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Definition
| bone marrow and active immune system destroyed completely - rebuilt with transfer of bone marrow |
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Term
| what is opposite of hypersensitivity or overreaction of immunity |
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Definition
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Term
| what are the two types of immunodeficiency |
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Definition
| primary (congenital) and secondary (acquired) |
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Term
| primary immunodeficiency caused by what |
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Definition
| result from genetic defect or from environmental factors that cause developmental abnormalities |
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Term
| secondary immunodeficiency caused by what |
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Definition
| result of infection or other stress on immune system (such as malnutrition) |
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Term
| which is generally rare - primary or secondary immunodeficiency, example |
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Definition
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Term
| categories of primary of immunodeficiencies (4) |
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Definition
| antibody deficiencies, lymphocyte deficiencies, defects in phagocytic cells, defects in complement system components |
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Term
| most common antibody deficiency - which antibody affected |
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Definition
| IgA - little or none produced, mucous membranes not protected, lots of infections there |
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Term
| key disease of lymphocyte deficiency (primary) |
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Definition
| SCID - sever combined immunodeficiency, bone marrow stem cell defect - no T cells or B cells produced, generally die unless bone marrow transplant |
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Term
| defect in phagocytic cells (primary) caused by |
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Definition
| (CGD - chronic granulomatous disease) - failure of lymphocyte to produce H2O2 and other active products, suffer from recurrent pus forming infections |
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Term
| defect in complement system (primary)- what type of infections caused |
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Definition
| neissaria - typically killed by MAC's, don't form properly |
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Term
| what factors can lead to development of secondary immunodeficiency (6)? |
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Definition
| malignancies, advanced age, pregnancy, infections (esp viral), immunosuppressive drugs, malnutrition |
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Term
| what is a virus that particularly causes secondary immunodeficiency |
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Definition
| measles - replicates in cells of immune system, depletes them, leaves body open to infection |
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Term
| besides AIDS, other key secondary immunodeficiency diseases |
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Definition
| syphilis, leprosy, malaria |
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Term
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Definition
| HIV retrovirus infects and destroys helper T cells, opportunistic infections attack |
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Term
| what is multiple myeloma (secondary) |
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Definition
| malignancy arising from single plasma cell that proliferates out of control and produces large quantity of immunoglobulin of one type, depletes stores of others |
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