Genetic and serologic analysis of feline cell-associated herpesvirus-induced infection of the urinary tract in conventionally reared cats.

The genetic and antigenic nature of feline cell-associated herpesvirus (FeCAHV) was characterized by use of DNA restriction endonuclease analysis, and direct and indirect fluorescent antibody (FA) techniques. Serologic responses of 6 conventionally reared cats with induced FeCAHV urinary tract infection were retrospectively evaluated, using an indirect FA test. The EcoRI, HindIII, and Pst I restriction endonuclease cleavage patterns of FeCAHV DNA were similar to those of bovid herpesvirus 4 (BHV-4; DN599 strain) DNA. Specific fluorescence was observed when FeCAHV-inoculated cell monolayers were reacted with fluorescein-conjugated BHV-4 (DN599 strain) antiserum. Conversely, specific fluorescence was also observed when feline anti-FeCAHV serum and fluorescein-conjugated caprine anti-feline IgG was reacted with BHV-4 (DN599 strain)-infected cell monolayers. At postinoculation week 10, serum antibody titer in cats with FeCAHV-induced urinary tract infection ranged from 1:2,560 to 1:10,240, as measured by use of indirect FA testing. It was concluded that FeCAHV is a member of the BHV-4 group. In addition, the FeCAHV indirect FA test provides a sensitive and specific means of evaluating FeCAHV antibody concentration in exposed cats.