innate defense, network of inactive serum proteins and cell surface receptors
Pattern recognition pathway
activation of compliment by molecules in microbes (usually carbs), activated innate immunity
associated with acquired immunity
compliment becomes activated when antibodies bind to surface, work with acquired to destroy microbe
function of complement system
alter cell membranes or induce inflammation
hastens elimination of invader
induces bacterial lysis, opsimization (makes pathogen more susceptible to phagocytosis)
makes pathogen more susceptible to phagocytosis
microscopic molecule can bind to surface of large pathogen so other cells can more easily eat invader
alter membranes (bacterial lysis, opsimization)
inflammation (mast cell degranulation, neutrophil chemotaxis to attract phagocytes)
other (immune regulation, angiogenesis, removal of apoptotic cells
acquired or adaptive immunity
antigen-SPECIFIC immune response to a particular substance that the body IDs as "non-self"
directed against specific pathogen
Slower, but LEARNS, long-lasting
does not fully develop unless body has been previously exposed to that specific pathogen
2 types: Cell-mediated (T and B cells) and Humoral (antibody-mediated)
auto-immune disease is a mistake in the
acquired immune system
cells of innate vs adaptive
innate: macrophages, dendritic, neutrophils, natural killers (sentinel and phagocytic)
adaptive: T and B cells
any substance that can induce a specific immune response
usually a large protein molecule recognized by cells of acquired
Antigen presenting cell
usually macrophage, dendritic cell, some B cells
Traps and processes antigen
presents antigen to immune system cells who take care of it.
Process antigen, present it on surface, T-helper recognizes, B cell coated in receptors binds to same antigen, tell B to become memory or plasma, plasma cell produces antibodies specific to antigen, make antibody-antigen complex.
Why do we need 2 types of acquired immunity?
exogenous antigens openly proliferate, can be found by antibodies (humoral)
intracellular pathogens proliferate in cell and are taken care of by cell-mediated immunity (not accessible to antibodies)
B-cells proliferate in
lymph nodes, sometimes in secondary lymph organs like spleen
Antigen-specific, usually not seen for at least a week after exposure (can't test right away)
Bind to antigen they are specific to, cause antigen/antibody complex
Serum protein electrophoresis
test. Apply electric field to sample, molecules separate by size and charge. Run when see hyperproteinemia characterized by hyperglobulinemia.
Albumin most negative, rest separate into alpha, beta and gamma.
Gamma is immunoglobulins.
Look for spike--is it one Ig or several? Monoclonal vs polyclonal gammopathy
highest concentration in serum, longest half life (in circulation longest), smallest molecule (escapes vaso in inflamm)
defense of tissues, can bind to pathogens and specific antigens, causes bacteria to clump and activates opsimization (more susceptible to phagocytes) in classical compliment pathway
Produced in spleen, lymph, bone marrow (1 and 2 lymph tissue)
Predominant transferred from mom to offspring in colostrum
2nd highest concentration in serum, largest molecule so stays in circulation
antibody produced on initial exposure to antigen
primary immune response (also 2 but less)
More efficient than IgG in activation of opsimization, activation of compliment and neutralizing viruses
produced by plasma cells in 2 lymph organs (NOT bone marrow)
Shaped like a polygon, not linear like other Igs
third highest concentration in serum, predominate Ig found in body secretions of nonruminents
produced in body surfaces (guard at the gate), makes pathogens and viruses clump to each other and body surfaces "not sticky", major in preventing pathogen invasion.
Bord IN (airborne pathogens)
NOT increase opsimization or activate compliment
produced in respiratory, skin, urogenital, GI, cornea, mammary glands
3. deposition of antibody/antigen complex in tissue creates inflammation (glomerulonephritis, for example)
4. delayed, very slowly developing, mediated by T cells and natural killer cells. Takes 24-96 hours to develop.
low concentration in serum (shortest half life)
mediate allergic reactions, especially type I. Causes degranulation of mast cells if cross-linked, more than 1 IgE on surface
enhances local defenses, triggers acute inflammation (FC on mast and basophils) and compliment in PARASITIC WORM IMMUNITY
produced by plasma cells beneath body surfaces (respiratory, skin, urogenital, GI, cornea, mammary)
monoclonal vs polyclonal gammopathy
LOTS of Igs.
monoclonal could be cancer
polyclonal suggests infection (FIP?)
FC stands for
fragment receptor crystallized.
Steadier part on stem of antibody, antigen binding sites can change, FC is more constant
Acquired passive immunity, artificial and natural
Administer pre-formed antibodies from another immune animal (inject Ig)
Immediate but not long-lasting
artificial: antiserum, antitoxin
natural: colostrum/placenta, from mom
acquired active immunity, artificial and natural
IV organism (killed or modified live if artificial), animal fights.
Takes longer to develop, lasts longer
Repeated exposure makes immunity stronger, booster vaccines
administration of antigen to stimulate immune so individual can develop immunity
1st: development of effector T and B cells (helper, killer, suppressor), temporary protection
2nd: development of memory T and/or B cells, re-exposure (3rd), recognition, clonal expansion and differentiation into effector T and B cells, kill invader.
T or B cell that stops allergic response from going on, spares "self".
Types of vaccinations
Inactivated vaccine: virus or bacteria grown in culture then killed (formaldehyde or heat). Proteins remain intact enough to be recognized by immune (exogenous antigen) and stimulate mostly T helper cells (CD4)
Modified live vaccine: attenuation (goldilocks) to reduce virulence, stimulates response of mostly cytotoxic T cells (CD8), act as endogenous, cell-mediated immunity.
viral purified subunit: inject into another species
viral recombinant product: inject into another species
viral DNA vaccine: most recent, protein off capsid, purified
viral DNA vaccine
DNA that encodes antigen is injected into the individual
viral recombinant product
take gene responsible for coding of antigen, inject into another species or virus (cat rabies = canary pox)
viral purified subunit
most recent, take protein off capsid, purify and make vaccine from that
modified live vaccine
attenuated, strong enough to stimulate, too weak to replicate.
Response primarily cytotoxic T cells (cell-mediated, get into cells and replicate, endogenous)
fewer smaller doses required, more effective, adjuvents unnecessary, less chance of hypersensitivity, cheaper, given with natural route, stimulate humoral and cell mediated response, lover-lasting (3 year)
killed with formaldehyde or heat, mostly T helper cell response (acts as exogenous)
Stable on storage, safer, unlikely to cause disease, do not replicate, will not spread, safe in immunodeficient patients, easier to store, no risk of reversion
process that reduces virulence of virus in vaccine (goldilocks).
additives to enhance effectiveness so you need less. Often causes reactions.
vaccine for bacteria, almost always killed
vaccines began in
1940s, with smallpox
Cell-mediated immune response
defense inside cells where antibody can't reach.
Eliminate abnormal cells and intracellular organisms (endogenous)
cytoxic T cells (CD8) cause forced apoptosis
Cells leave lymph organs and seek abnormal cells. Don't wait to be presented.
immunodiagnostic technique, ELISA
most common primary binding test
Detect and measure antibodies.
Well is pre-coated with antigen, serum goes in well, makes a/a complex if present. Add anti-globulin (protein that binds to Ig, which is bound to a/a complex, sandwich), causes color change.