Week 5 Flashcards
(75 cards)
2 general approaches in immunoassays?
measuring specific Ag in sample
look for Ab specific for Ag of interest as evidence that the ind has been exposed to specific Ag
antiserum?
serum collected from an animal that has been exposed to Ag and thus contains Ab against that Ag
produced by immunizing the animal with the Ag of interest and collecting the serum
anti-species Ab?
produced when Ab from one species is collected and injected into another
ELISA?
enzyme linked immunosorbent assay indirect elisa is the most common: - coat wells with Ag - wash away unbound Ag - add serum - Ig binds Ag - wash away unbound Ab - enzyme conjugate - wash way unbound AB - substrate/ chemogen solution for coloraturas change
sanwhich ELISA?
2 Ab go on either side of target Ag
both Ab bind to different epitopes of Ag
substrate specific to enzyme linked Ab is added so we get coloraturas and a positive test which forms in Ag in the sample
SAT?
serum agglutination test
agglutinating Ab present in sera which react with specific Ag to form visible clumps
hemagglutination?
can chemically couple any Ag to RBC to detect Abs to that Ab
if sufficient Ab present to agglutinate and form cross links with Ag then Ab:Ag complex forms a mat at the bottom of the well
if insufficient Ab present then the cells roll down sides of well and forms a pellet down the bottom
direct coombs test?
detects Ab and complement on the surface of RBC
addition of anti-human Ig Ab to washed fetal RBC - they will agglutinate if maternal Rh-Ab were already coated on fetal RBCs
indirect coombs test?
detects Ab in serum
materna sera incubated with Rh+ Abs present in the maternal serum; if they agglutinate then anti-human Ig Ab are present
what immunoassay is used for syphillis testing?
serum agglutination test
what is a common test for HIV? why?
western blotting
AB to various HIV proteins appear at different stages post infection
point of care tests?
rapid test for Ab and Ag detection; lower specificity
drop mixture on sample pad
mixture flows on the membrane
positive signal detected as a line
what are the different flow cytometry tests?
elispot assay: for quantifying cells and producing cytokines
lymphocyte proliferation assay: for memory function and transplant matching
target cell killing assay: for measuring cellular cytotoxicity
microarrays or DNA/RNA chips: for screening large number of genes or samples
what does flow cytometry tell us about a cell?
relative size
granularity or internal complexity
how does flow cytometry work?
take blood sample and mix it with Ab that recognizes the Ag in which we are interested in
tag it with fluorescent tag so when its passed through flow cut-meter all the molecules will be counted (eg, CD4)
screening rules for avg risk of BrCa?
mammogram every 2 years from age 50-74
higher risk screening rules of BrCa?
mammogram every 2 years from age 50-74 and breast awareness (self-examination)
screening rules for cervical cancer?
HPV tests every 5 years from the age of 25 or 2 years after first sexual intercourse
end between 70-74 y/o
avg risk screening rules for Bowel cancer?
FOBT every 2 years from 50-74
higher risk screening rules for bowel cancer?
FOBT every 2 years from age 35-44
colonoscopy from 45-74 every 5 years
screening rules for skin cancer?
avg risk= primary prevention
moderate risk= primary prevention and skin exam
higher risk= preventative advice, examination of skin and advice on self-exam
what are some factors that come into play for primary prevention?
tobacco alcohol diet excercise/ obesity radiation chronic infections occupational exposure
whats the problem with PSA testing?
increased PSA is not solely specific for cancer but their is no precise way to tell
so men that undergo tx may experience side effects but don’t necessarily have PrCa = over tx and over dx
what are some scenarios for increased PSA/
carcinoma benign prostatic hypertrophy prostitis bike riding recent ejaculation
