Characterization of a new canine herpes virus

Abstract

SummaryA cytopathogenic agent, designated CHV-BI%, isolated from genital lesions in dogs has been shown to be a herpesvirus. It contained DNA, was ether-and heat-sensitive, and was unstable at low pH. Electron micrographs revealed a virion of typical herpesvirus structure. The CHV-BR isolate produced a marked cytopathic effect (CPE) in dog kidney cell cultures but failed to grow in rabbit kidney and human cell lines. The CPE in dog kidney cells consisted of extensive polykaryocytosis, and the formation of intranuclear type-A inclusion bodies. The emergence of a non-polykaryocytogenic CPE variant during serial passage of the isolate in dog cells was described. Neutralization and immunofluorescence tests showed that CHV-BI~ was serologically similar to the F-205 strain of canine herpesvirns (CHV) but was not related to other human and animal herpesviruses. Differences between the CHV-BR isolate and the CHV strains isolated elsewhere were discussed.

Small-plaque variant of canine herpesvirus with reduced pathogenicity for newborn pups

“…The mP-CHV, however, did not behave as an attenuated host range, temperature-sensitive mutant, as described for the large-and smallplaque mutants of HVH-2 (9,11). It did not regularly engender the formation of syncytia, as described for the CHV-BR strain (14), or occur as a naturally attenuated plaque variant, as described for field isolates of MDHV, but it origi-nated after less than 20 passages in DKC cultures incubated at 30'C after prolonged culture (312 passages) at 35°C. Unfortunately, the precise passage at which the mP variant emerged could not be determined, but it was the dominant type after 20 passages at 300C.…”

“…Plaque size comparisons of CHV strains. Analysis of the plaque characteristics of 14 CHV strains isolated at various times and from different geographical areas revealed an overall mean plaque size of 1.50 ± 0.09 mm at 350C (Table 1).…”

“…Growth of CHV is markedly restricted by the temperature of incubation, the optimal range being 35 to 370C (1,4). Plaque characteristics of several field isolates grown at optimal temperatures in primary dog kidney cell (DKC) cultures have appeared consistent in size and character (L. N. Binn, personal communication; 15,19), with the unique exception of the BR strain (14) isolated in England from the genital tract of dogs with vesicular lesions. The BR strain of CHV was unusual in that it caused plaques on DKC monolayers consisting principally of polykaryocytes.…”

Properties and Functions of Feline Herpesvirus Type 1 Glycoproteins.

“…None of the vaccines so far developed has been able to provide complete protection in terms of preventing viral replication on re-exposure, but clinical protection is adequately provided. It is unknown whether vaccination can prevent the establishment of a carrier state [22,62].…”

“…The virus grows exclusively in cell types of only canine origin such as primary canine kidney cell cultures and Madin-Darby canine kidney (MDCK) cell line [6,10,62,78]. CHV gD adsorbs to canine RBC, not to feline RBC [47].…”