DNA damage of blood lymphocytes and neutrophils in cattle with lymphosarcoma

The objective of the present study was to analyze the apoptotic process in peripheral blood mononuclear cells (PBMC) and polymorphonuclear neutrophil leukocytes (PMN) in cows clinically affected with lymphosarcoma. Thirteen cows were studied. Of them, eight, that were referred because of inappetance, loss of body condition, diarrhoea, constipation, protrusion of third eyelid, and exophthalmia, were seropositive for bovine leukemia virus (BLV) based on a serum enzyme-linked immunosorbent assay. Other animals were apparently healthy and were used as controls. DNA damage of PBMC and PMN was assessed using the Comet assay. The results obtained showed a statistically significant difference in DNA damage between the PBMC and PMN isolated from cows infected with BLV compared to PBMC and PMN isolated from healthy cows. This is the first article to document decreased apoptosis of blood PBMC and PMN in cattle in response to BLV infection using the Comet assay.