O Papilomavírus bovino (BPV) gera prejuízos à pecuária. O trabalho buscou isolar vírions de BPV de papilomas cutâneos previamente diagnosticados e avaliar o potencial clastogênico do vírus através do ensaio cometa (EC). O DNA tecidual foi extraído e submetido a PCR. As bandas foram purificadas e sequenciadas. As sequências foram analisadas através de bioinformática. A tipagem mostrou a prevalência de BPV-2. A análise histopatológica revelou acantose, coilocitose e hiperqueratose. Foi possível detectar a presença de fibroblastos transformados, sugerindo uma via de infecção através do sangue. A imuno-detecção das proteínas L1 e E7 no estroma sugere atividade transformadora do BPV em fibroblastos. O EC mostrou a ação clastogênica estatisticamente igual entre os tipos virais BPV-2, 5 e 9. O isolamento viral foi realizado através de ultracentrifugação em densidade única de cloreto de césio, empregando uma nova metodologia, que se mostrou menos laboriosa do que as já descritas, permitindo o isolamento de vírions de BPV-2, iniciando o banco de vírus proposto.

The Bovine papillomavirus (BPV) generates losses to livestock. The study sought to isolate BPV virions from cutaneous papillomas previously diagnosed and evaluate the clastogenic potential of the virus through the comet assay (EC). The tissue DNA was extracted and subjected to PCR. The bands were purified and sequenced. Sequences were analyzed using bioinformatics. The typing showed the prevalence of BPV-2. Histopathology showed acanthosis, hyperkeratosis and koilocytosis. It was possible to detect the presence of transformed fibroblasts, suggesting a route of infection through the blood. Immunohistochemical detection of L1 and E7 proteins in the stroma suggests transforming activity of BPV in fibroblasts. The EC clastogenic action showed statistically equal among the virus types BPV-2, 5 and 9. Viral isolation was performed by ultracentrifugation in a single cesium chloride density, using a new method that was less laborious than those already described, allowing the isolation of BPV-2 virions, starting the proposed stock virus.