EN
Lymphocyte blastogenesis was determined by ³H-thymidine incorporation assay after stimulation of the cell cultures with mitogens: Concanavalin A, phytohaemagglutitin, and pokeweed mitogen. BIV and/or BLV infection were associated with significant changes in lymphocyte blastogenesis to mitogens. The highest responses to all three mitogens were shown by 3 to 4.5 months after infection when compared to control animals, and thereafter were depressed at the end of the experiment Stimulated lymphocytes revealed in 20 - 50 fold increase in blastogenesis over background based on the unstimulated cells. These results demonstrated that a function impairement of lymphocytes can be observed in the course of BLV and/or BIV infection.