Correlation of Immunofluorescence and Infectivity in the Developing Bovine Cutaneous Papilloma.

Bovine papilloma antigen detected by fluorescent antibody was correlated with the appearance of infectious virus and with epithelial hyperplasia and hyperkeratinization in the developing bovine cutaneous papilloma. Neither antigen nor infectious virus was found in the earliest stages of growth characterized by connective tissue pro liferation and by little or no epithelial change. The cellular localization of papilloma virus antigen in nuclear material of the superficial epithelium was the same when first observed as it was in the well developed wart. Regression of the warts was accom panied by a decrease in specific antigen. Marked variations in susceptibility of in dividual calves to bovine papilloma virus were observed, as well as differences in the histologie development of warts produced by virus administered intradermally and by scarification.