Intracellular Reactive Oxygen Species Production by Polymorphonuclear Leukocytes in Bovine Leukemia Virus-Infected Dairy Cows

Abstract

The present study assesses the oxidative burst activity from polymorphonuclear leukocytes (PMNL) from bovine leukemia virus (BLV)-infected cows. Fifteen clinically healthy cows were divided in serologically positive cows without any hematological alteration, serologically positive animals with persistent lymphocytosis (PL) and healthy serologically negative cows. The oxidative burst activity from PMNL was evaluated by flow cytometry using 2',7'-dichlorofluorescein diacetate as a probe. PMNL from each cow were incubated with heat-killed Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) to stimulate oxidative burst activity. The results of the present work showed no significant difference in oxidative burst activity without any stimulus and elicited by S. aureus. Conversely, a decrease in the oxidative burst index induced by E. coli in PMNL was observed in BLV-infected cows.