CPA #19 Questions Flashcards
Define: active immunization
administering antigens to a patient so that the patient actively creates an adaptive immune response
define: passive immunotherapy
patient acquires temporary immunity through the transfer of antibodies formed by other individuals or animals
who developed vaccines?
Edward Jenner
where does the name vaccine come from?
vaccina, another name for cowpox
define: vaccine
protective, antigenic inoculum
define: immunization
the administration of a vaccine
how do you measure the effectiveness of a vaccine?
measuring the antibody level (titer) in the blood.
what happens if the effectiveness of a vaccine is low?
administration of more antigen (booster immunization)
what are the 5 types of vaccines?
- attenuated
- inactivated
- toxoid
- combination
- recombinant gene
define: attenuated (modified live) vaccines
reducing the virulence of a microbe so that it is less likely to cause disease; attenuation; due to being a live pathogen, vaccinated individuals can infect those around them (contact immunity)
define: attenuation
the process of reducing virulence of a microbe
define: contact immunity
immunity beyond individual receiving the vaccine due to infection of the live pathogen from the modified live vaccine
what are the pros and cons of attenuated vaccines?
pro: usually very effective
con: may retain enough residual virulence to cause disease in immunosuppressed individuals
define: adjuvants
substances that increase the effective atigenicity of the vaccine by stimulating immune cell receptors and their actions
define: toxoid vaccine
chemically or thermally altered toxins that are used in vaccines to stimulate active immunity
pros and cons of toxoid vaccines
pro: few antigenic determinants
cons: multiple does and boosters every 10 years
define: combination vaccines
combine antigens from several attenuated and inactivated pathogens and toxoids are administered simultaneously; ex MMR
Define: recombinant gene vaccine
genetically altered vaccines
how are vaccines made
grow bacteria in a lab or a virus in a chicken egg
who cannot receive. vaccines?
people allergic to eggs
define: herd immunity
protection provided to all individuals in a population due to the inability of a pathogen to effectively spread when a larger proportion of individuals are resistant
who contributes to herd immunity? how?
CDC; recommended immunization schedules for children, adults, special populations to increase the number of individuals with the vaccine at one time
what are risks associated with vaccines?
mild toxicity; anaphylactic shock; residual virulence;
what diseases are claimed to be caused by vaccines?
autism, diabetes, asthma
what are 3 limitations of passive immunotherapy?
repeated injections of animal-derived antisera can trigger an allergic response (serum sickness); patient may degrade the antibodies relatively quickly (protection is short-lived); body does not produce memory B cells in response to passive immunotherapy
define: serum sickness
recipient mounts an immune response against animal antigens
when is passive immunotherapy preferred over active immunization?
when immediate protection is needed
what are precipitation tests?
serological test; when antigens and antibodies are mixed in proper proportions, the form precipitates
define: immune complex
precipitation test; soluble antigen is mixed with antiserum against the antigen; mixture quickly becomes cloudy because of formation of precipitate
define: immunediffusion
wells in agar plate; one well is filled with serum; one well is filled with antigen solution; antigens and antibodies if present diffuse in all direction; where they meet in perfect combination = precipitation line
what are similarities of turbidimetric and nephelometric tests
used to quantify amounts of proteins in serum
define: turbidimetric
light detector measures the amount go light passing through a solution
define: nephelometric
machine measures the amount of light reflected from the antigen-antibody complexes
define: agglutination testing
adding antibodies to sample; clumping occurs when reacting to certain antigens; titration
define: titration
measuring antibody levels; serum being tested undergoes a regular series of dilutions, and each dilution is then tested for agglutinating activity
define: neutralization tests
antibodies can neutralize the biological activity of many pathogens and their toxins; viral neutralization & viral hemagglutination tests
define: labeled antibody tests
serological test that use antibody molecules that are linked to a molecular “label” that enables them to be detected easily; radioactive chemicals, florescent dyes, and enzymes
define: direct fluorescent antibody tests
identify the presence of antigen in a tissue
define: indirect fluorescent antibody tests
presence of specific antibodies
why do we use indirect and direct antibody tests?
direct: to detect small number of bacteria in patient tissue
indirect: antibodies against many viral, protozoan, or bacterial pathogens
define: ELISA’s
enzyme linked immunosorbent assay; label is an enzyme; reacts with substrate and produces a colored product if positive
define: western blot
aka immunoblot; used to detect specific protein (antibody)
how is a western blot different than a Northern/southern?
western used proteins; northern = RNA, southern = DNA
define: immunofiltration assays
rapid ELISAs; antibodies bound to membrane filter
define: immunochromatographic assays
used for pregnancy testing;
define: immune hypersensitivities
allergies
define: autoimmune disease
immune system attacks own tissues
define: immunodeficiency disease
immune system fails
define: type I hypersensitivity
localized or systemic reactions that result from release of inflammatory molecules in response to antigen; immediate hypersensitivities (develop within seconds)
define: allergies
aka type I hypersensitivities
define: allergens
antigens that cause allergies
define: mast cells
specialized WBCs; distributed throughout body in connective tissues other than blood
define: histamine
stimulates strong contractions in smooth muscles of bronchi, GI tract, uterus, and bladder; dilates RBCs
what cells secrete histamine?
mast cells, basophils, eosinophils
define: hay fever
local allergic reaction; runny nose, sneezing, itchy throat/eyes, watery eyes
define: urticaria
aka hives; latex, wool, certain metals, venom/saliva of bees, flies, fleas, etc.
define: asthma
hypersensitivity I; severe difficulty breathing; wheezing, coughing, excessive mucous production
define: anaphylactic shock
aka anaphylaxis; release of chemicals beyond the bodies ability to adjust
how can you prevent type I hypersensitivity?
identify and avoid the allergens
how do antihistamines treat Type I Hypersensitivity?
counteract histamines
how does epinephrine treat Type I Hypersensitivity?
emergency treatment; quickly neutralizes many of the lethal aspects of anaphylaxis; relaxes smooth muscle of lungs, contracts smooth muscle of blood vessels; reduce vascular permeability
define: type II hypersensitivity
aka cytotoxic; cells are destroyed by immune response; part of many autoimmune disorders; incompatible blood transfusions
define: type III hypersensitivity
aka immune-complex mediated; small immune complexes escape phagocytosis and circulate in blood stream until they become trapped in organs, joints, and tissues; localized or systemic
define: hypersensitivity pneumonitis
minute mold spores are inhaled deeply into the lungs; causing production of mold spores
name 4 types of hypersensitivity pneumonitis
farmers lung, pigeon breeders lung, mushroom growers lung, librarians lung
define: glomerulonephritis
immune complexes circulating in the bloodstream are deposited into the walls of glomeruli (kidneys)
define: rheumatoid arthritis
type III hypersensitivity; autoimmune disease; B cells secrete IgM that binds to IgG molecules that are deposited into the joints; inflammatory chemicals are secreted and tissues swell, thicken, destroys cartilage
define: SLE
systemic lupus erythematous (lupus); type III hypersensitivity; auto-immune disease; produce antibodies against antigens found in many different organs
define: type IV hypersensitivity
aka delayed hypersensitivity; aka cell-mediated hypersensitivity; results from interactions among antigen, APCs, and T cells
define: tuberculin response
used to diagnose contact with M. tuberculosis; shallow injection of tuberculin
define: allergic contact dermatitis
plants (poison ivy) secrete oil that triggers an immune response and results in an intensely irritating rash
define: graft rejections
perceived as foreign; type IV hypersensitivity reaction;
define: autograft
graft from self; does NOT need immunosuppressants
define: isograft
graft from twin/clone; does NOT need immunosuppressants
define: allografts
graft from within same species; DOES NEED immunosuppressants
define: xenografts
graft from animal; DOES NEED immunosuppressants
define: graft-vs-host disease
donated bone marrow T cells may regard the patients cells as foreign and start an immune reponse
what is the key factor for donor-recipient matching
MHC proteins
define tissue typing
WBCs of potential graft recipients to determine the MHC proteins; must be at least 50% MHC match to donor for most organs, almost 100% match for bone marrow
