DEVELOPMENT OF A SIMPLE, RAPID AND ACCURATE IN-VITRO WHOLE-BLOOD TECHNIQUE FOR THE DETECTION AND SEMI-QUANTIFICATION OF FIV CELLULAR VIREMIA

A new, simple, rapid and accurate culture technique is described for a semi-quantitative analysis of cellular viremia in FIV-infected cats. This assay can be carried out with small amounts of whole blood, and i s based on the detection of FIV core gag antigen, which is released in culture supernatants. The amount of core antigen produced is measured with an enzyme-linked immunoassay using specific monoclonal antibodie s. This whole blood technique (WE method) was compared with a culture method using isolated peripheral blood mononuclear cells (PBMC method) . FIV could be detected in whole blood of all experimentally infected cats, but not from uninfected cats. This assay offers a number of adva ntages (small blood samples required, no leukocyte separation and lymp hocyte purification procedures) and its reproducibility is very good. It provides a convenient in vitro cellular assay for viral semi-quanti tation, well adapted for monitoring efficacy of prototype FIV vaccines or experimental antiviral drugs. Also, it could facilitate the study of the pathogenesis of FIV-related progressive immunodepression. Final ly, it offers an alternative to serological techniques for diagnostic purposes in several circumstances: early viremia, maternal antibodies ...