Incomplete human adenovirus replication in canine tumour cells and serological evidence of infections in tumour-bearing canine pets

Abstract

Concentrations of newly synthesized virus antigens and virions in cultures of canine normal and tumour cells after inoculation with equal input multiplicities of human adenovirus types 5, 21 and 31 and infectious canine hepatitis virus (ICHV) were measured by solid phase bead-type radioimmunoassay (SBRIA) and fluorescent antibody techniques with human and canine adenovirus-specific reference sera. Higher concentrations of human adenovirus antigens were detected in inoculated tumour cells than in inoculated normal cells, although no infectious human adenoviruses were detected in either of the inoculated canine cell types. In other cultures of these same canine cells, markedly higher concentrations of both ICHV antigens and progeny virions were detected in infected normal canine kidney cells than in infected neuro-fibrosarcoma cells. Human adenovirus type 5 neutralizing antibody was detected in the sera of 2 of 24 dogs bearing untreated malignant tumours and in the serum of 1 of 20 normal dogs. SBRIA tests showed significantly higher concentrations of human adenovirus antibody in the sera of dogs with tumours than in sera from normal dogs. Concentrations of human Ad5 antibody were greater than those of Ad21 and Ad31 antibody in the sera of both normal and tumour-bearing canine pets, each of which had a history of regular vaccination and of long-term close contact with man. Concentrations of ICHV antibody as measured by virus neutralization and SBRIA tests in sera from normal pet dogs were not significantly different from those detected in sera from tumour-bearing dogs. Supported in part by NIH-NCI-NOI-CB-84 248.