In article <3mhkbk$m3r at newsbf02.news.aol.com>, susand4739 at aol.com (SusanD4739) writes:
> What is at titer. Something to do with antibodies, right? Or IFA's, or
> something. Tell me!
titrate (vt) to determine the concentration of something in solution by reacting
it with a known amount of something else; e.g. determine concentration of acid
in solution by neutralizing with a known volume of a base at known
concentration. The assay requires the attainment of some readable end-point (eg
color change in your pH indicator).
In the context of virology, titration tells you the concentration of virus (
i.e. the virus titre) in a liquid sample. This can be determined by serially
diluting the sample and asking how many cells in a dish can be infected by a
known volume at known dilution. Alternatively a titre can be determined by
less precise methods such as asking how dilute your sample can be and still
agglutinate erythrocytes (a talent shared by many viruses), or infect an egg, or
make a mouse sick, or whatever else your endpoint is...
Similarly, the amount of antibody in a solution can be determined by asking
how much of a sample of virus the antibody can neutralize.
Kevin W. Ryan
Department of Virology & Molecular Biology
St. Jude Children's Research Hospital
Memphis, Tennessee 38101-0318, U.S.A.
phone: (901) 522-0411
fax: (901) 523-2622
Internet: ryan at mbcf.stjude.org