Adaptive Immunity

Why is it important to tell your doctor if you’re on steroids?

because it suppresses your immune system

What did Edward Jenner do?

variolated a boy using cowpox scab for small pox

What are the two kinds of acquired immunity?

natural and artificial immunity

What is natural immunity?

acquired through normal life experiences and not induced through medical means; active or passive

What is natural active immunity?

consequence of a person developing his own immune response to a microbe (infection)

What is natural passive immunity?

consequence of one person receiving preformed immunity made by another person (breastfeeding)

What is artificial immunity?

produced purposefully through medical procedures

What is artificial active immunity?

consequence of a person developing his own immune response to a microbe (immunization)

What is artificial passive immunity?

consequence of one person receiving preformed immunity made by another person (antibody transfer)

What are the two branches of adaptive immunity?

humoral (b cells) and cellular (t cells)

What does the complement system do with innate immunity?

opsonization, lysis of pathogens, chemotaxis, inflammation, cell activation

What does the complement system do with the disposal system?

clearance of immune complexes and apoptotic cells

What does the complement system do with adaptive immunity?

augmentation of antibody response, promotion of T cell response, elimination of self-reactive B cells, enhancement of immunologic memory

What are the three major functions of adaptive immunity?

recognize non-self, respond to non-self, remember non-self (immunological memory)

What is a superantigen?

microbial toxin that causes non-specific T cell activation, lots of inflammation, toxic shock syndrome

What are antigens?

foreign proteins, nucleic acid, some lipids, and large polysaccharides over 1000 Da

What is alpha-gal?

sugar polysaccharide from ticks recognized by T cells; same thing in red meat

What are haptens?

small molecule that cannot trigger an immune response on its own but can prompt immune system to make antibodies (penicillin)

How do cells identify each other?

different types of receptors, cytokines, and chemokines

What kind of cells have MHC Class I?

all cells

What kind of cells have MHC Class II?

antigen presenting cells and B cells

What is MHC Class III?

rare; in organ transplants and HLA (human leukocyte antigens)

T-independent stimulation of B cells means?

no memory cells produced

How are T cells differentiate?

stem cells develop in bone marrow or in fetal liver, goes to thymus to differentiate into T cell; migrates to lymphoid tissues (spleen or lymph nodes)

How do B cells differentiate?

stem cells develop in bone marrow or in fetal liver, goes to red bone marrow to differentiate into T cell; migrates to lymphoid tissues (spleen or lymph nodes)

What are cytotoxic T cells?

produce toxic agents to kill their targets

What are helper T cells?

stimulate B cells to make antibodies; stimulate T cells to become active

What are regulatory T cells?

suppress immune responses

What is the difference between cytotoxic T cells and NK cells?

one recognizes ID and NK doesn’t

What is clonal selection?

B cells needs to be exposed to antigen to become plasma cell

What is the structure of an antibody/immunoglobulin?

Fc is the stick, arm tips have variable region and everything else is constant; light and heavy chain on each side so four chains on each; crystallizable

What is GAMDE?

antibody classes that are the highest to lowest percentage in the body

What is IgA?

helps prevent the attachment of pathogens to membrane surfaces; dimer

What is IgD?

important in B cell activation

What is IgE?

binds to mast cells and basophils, causing histamine release during allergies

What is IgG?

the most abundant and diverse antibody; memory antibodies

What is IgM?

pentamer released by plasma cells during the primary immune response

What are the consequences of antigen-antibody binding?

precipitation, opsonization, agglutination, complement fixation, neutralization

How does our immune system resist bacterial infection?

opsonins, IgM and IgG agglutinate, MAC, complement proteins attract phagocytic cells, neutralize bacterial exotoxins, cytokines attract and stimulate macrophage, cytokines stimulate T cells cell-mediated response

How does our immune system resist viral infection?

neutralize viruses, viruses opsonization, INFs cause the death of infected cells and stimulate the activity of T cells, NK cells stimulated by interferons and antibodies, cytotoxic T lymphocytes destroy virus-infected cells are also involved in the destruction of cancer cells by a process known as immune surveillance

Why do we get mosquito bug bites?

female mosquitos need extra proteins from blood because they lay eggs; blood will clot, mosquito has anticoagulant that is what we react to

What are the symptoms of anaphylaxis?

loss of consciousness, hives, swelling of tongue, rapid swelling of throat tissues

What is differences between systemic and localized anaphylaxis?

whole body reaction vs standard allergic reactions

How does epinephrine work?

relaxes smooth muscle in the airways, counteracts histamine and other cytokines, raises blood sugar level, raises heart rate, BP, and myocardial oxygen demand

What is type I hypersensitivity?

IgE bound to mast cells; causes localized and systemic anaphylaxis, seasonal allergies, and food allergies

What is type II hypersensitivity?

cells are destroyed by bound IgG either by cytotoxic T cell or complement; red blood cells destroyed by complement and antibody during a transfusion of mismatched blood type or during erythroblastosis fetalis

What is type III hypersensitivity?

antigen-antibody complexes deposited in tissues, causing activation of complement which attracts neutrophils to the site; causes immune complex disease

What is type IV hypersensitivity?

Th1 cells secrete cytokines which activates macrophages and cytotoxic T cells and can cause macrophage accumulation at the site; contact dermatitis, tuberculin reaction, autoimmune diseases

What are T memory cells?

antigen-experiences cells that mediate a faster and more potent response upon repeat encounter with antigen; generated from effector T cells; occur in the mucosal tissue sites of the gut and lungs; react to the antigen-bearing pathogens in the mucosal tissue sites

What are B memory cells?

generated in response to T-dependent antigens; occur in blood stream; produce antibodies against the antigen

What is autoimmunity?

immune system doesn’t know the difference between self and non-self; influenced by environmental factors, genetics, immune system, and hormonal factors

What is an isograft?

tissue or organ transplant between two individuals who are genetically identical

What is an autograft?

transplant within an individual

What is an allograft?

transplant with a non-identical individual

What is a xenograft?

transplant between species

What is type I diabetes treatment?

have insulin producing cells without HLA so T cells don’t recognize it

Why is neutralization important for tetanus?

make antibodies beforehand with the vaccine to work against the toxin

What are the different types of immune disorders?

hypersensitivities, autoimmune diseases, transplantation rejection, immunodeficiencies