An enzyme linked immunosorbent assay (ELISA) for the detection of feline immunodeficiency virus (FIV) antigen in cell culture and FIV specific antibodies in feline serum.

Recently, a newly discovered lentivirus--Feline Immunodeficiency Virus (FIV)--was identified as the cause of an AIDS-like syndrome in the cat. For the detection of FIV antigen in cell culture, an antigen capture ELISA was developed. In this assay FIV specific IgG was used as a capture antibody and the same preparation coupled to biotine as a conjugate. With this test viral antigen could be demonstrated in FIV infected cell cultures within four days after infection and the assay proved to be at least as sensitive as a reverse transcriptase test in demonstrating virus infected cultures. A modification of this assay in which a titrated amount of FIV antigen was incubated with dilutions of serum samples of naturally or experimentally infected cats, allowed the detection of FIV specific antibodies. In a serological survey, conducted among cats with different clinical histories in The Netherlands and The Federal Republic of Germany, the antibody inhibition ELISA was compared with a commercially (IDEXX) available indirect ELISA system. It was shown that both assays identified nine seropositive cats among 200 animals with a history of undefined chronic disease, whereas no positive reactions were obtained with 65 serum samples from apparently healthy animals. Both assays also gave positive results with serum samples from experimentally infected cats, within five weeks after infection. Of an additional panel of eight serum samples which had been found positive in the IDEXX indirect ELISA system, only five were found positive in the antibody inhibition ELISA and western blotting assay.(ABSTRACT TRUNCATED AT 250 WORDS)