LAB 4/5

immunoassay

used to (eia) detect presense of HSV-2 antibodies in serum. detecting label is horseradish peroxidase

eia steps

coat w known ag, block, add serum, wash, add antihuman ab conguagted w enzyme, add substrate for enzyme, read colour

why are eia sensitive

one enzyme molecule can interact w multiple molecules of substrate, amplifying signal

role of known pos and neg control sera

to validify results, and allow for reproduceability

consequences of neonatal HSV

abortion, stillbirth, congenital defects, neonatal sepsis, death - baby must be born via c section

chlamydia and msu

cannot be found in msu, cells infected tend to live in epithelial cells i.e. urethra

gram neg stains

pink

treatment for trachimonas pallidium

penicillin

RPR use

uses cross reactive Ab to cardiolipin, correlated with disease activity. confirms active infection w EIA - non specific. another is done after treatment is resolved

why was a gc biplate used for don

as gonorrhea was suspected - is a selective media that prevents too many commensals

what should don also be tested for

HIV, HPV if he has a history, HSV only tested for pregnant women, so need to find history of contacts

eia limitations syphillis

usually ab remain positive for life = cannot determine current or previous infection

lamp assay steps

lysed to release na, add master mix, incubate - yellow = pos, pink = neg

would u need to culture an organim to treat a patient w gonorrhoea after using pcr

yes - pcr is a piece of genome, need to use wgs to get whole organism to test for amr and treat patient

key steps in plaque assay

serial dilution of inoculum, place in a tissue culture plate with mdck cells. a monolayer of mdck cells forms, where virus infected cells die in a cytopathic effect, forming plaques that can be counted as plaque forming units.

you have 100 ul of diluted vs sample. what is the volume correction factor?

10

calc for plaque forming units

plaque count x reciprocal of dilution factor x volume correction factor

purpose of plaque assay following virus culture

to quantify viral load and to allow for further applications i.e. amr test

disadvantages plaque assay

takes longer and cannot be completed in field

high virus titre

indicates source of infection

advantages/disadvantages of lamp compared to PCR

quicker than pcr and can be used in field, disad is qualitative data, product cannot be used for further assays, false pos

pcr advantages

more specific, quantitative and allows for further analysis by gel electro

antivirals for HSV

acyclovir - nucleoside analogue that can prevent/ reduce blistering