Anti-FIV P24 Monoclonal antibody, Clone RCM5-4E3

Mazur C., Reis J.K.P., Leite R.C., Danelli M.G.M., Hagiwara M.K. & Medeiros M.A. 2010. Evaluation of a recombinant p24 antigen for the detection of Feline Immunodeficiency Virus-specific antibodies. Pesquisa Veterinaria Brasileira 30(10): 877880. Laboratorio de Viroses Veterinarias, Universidade Federal Rural do Rio de Janeiro, Seropedica, RJ 23890-000, Brazil.E-mail: mazur@ufrrj.br Feline Immunodeficiency Virus is a worldwide infection and is considered a significant pathogen. The diagnosis of FIV infections is mainly based on commercially available rapid tests that are highly expensive in Brazil, hence it is rarely performed in the country. Furthermore, lentiviruses grow slowly and poorly in tissue cultures, making the production of viral antigen by classic means and thus the establishment of FIV immunodiagnosis impracticable. In order to deal with this, recombinant DNA techniques were adopted to produce the protein p24, a viral capsid antigen. The protein's reactivity evaluation analyzed by Western blot indicated that this recombinant antigen can be a useful tool for the immunodiagnostic of FIV infections.

A colorimetric reverse transcriptase assay (cRT assay) was developed for quantitative detection of HIV-1. In this format, reverse transcriptase incorporates biotin-labeled dUTP onto oligo-dT primers hybridized to poly A templates. The templates are covalently bound to the surface of microtiter wells. The amount of incorporated biotin-labeled dUTP is measured by binding horseradish peroxidase conjugated streptavidin, washing away unbound peroxidase, adding colorimetric substrate and then reading with a standard colorimetric reader. The sensitivity of the assay is very good. As little as 3 X 10(5) molecules of recombinant HIV-RT can be detected after 20 h of reaction time. Direct comparison using 3 cultured clinical isolates indicates that this level of detection is equivalent to the commercially available p24 antigen capture assay and the HIV-RNA assay based on branched DNA signal amplification. Other retroviruses, such as HIV-2 and feline immunodeficiency virus (FIV), can also be detected in this format. This non-isotopic assay is easy to perform and could provide a convenient and quantitative method for HIV study by monitoring reverse transcriptase, an essential activity in the infection process.