GAG-SPECIFIC AND ENV-SPECIFIC SERUM ANTIBODIES IN CATS AFTER NATURAL AND EXPERIMENTAL-INFECTION WITH FELINE IMMUNODEFICIENCY VIRUS

In order to monitor the antibody response to feline immunodeficiency v irus (FIV) in cats, following experimental and natural infection, enzy me-linked immunosorbent assays (ELISAs) were developed using recombina nt env and gag proteins and p24-specific monoclonal antibodies. It was shown that in experimentally infected cats an env protein-specific an tibody response was directly followed by a gag protein-specific respon se. Furthermore, an ELISA for the detection of env protein-specific se rum antibodies proved more sensitive in identifying experimentally and naturally infected cats than ELISAs demonstrating gag protein-specifi c antibodies. It was concluded that, like in HIV infection of humans, the detection of env protein-specific serum antibodies in addition to gag protein-specific antibodies is not only an important tool in the d iagnosis of the infection but also in studies concerning the pathogene sis of the disease.