Abstract
A new yeast ingestion method was developed to deplete the monocytes from bovine mononuclear cells (MNCs), and applied for the investigations of the monocyte-lymphocyte interactions as well as of the effects of chemical treatments such as indomethacin, 2-chloroadenosine and mitomycin C on lymphocyte blastogenesis. Blood was incubated with yeast solution (0.8-1×109/ml)(1/10 volumes) at 37°C for 1 hr, then lymphocytes were isolated by density centrifugation. Lymphocyte cell suspension contained 0.8±0.7% monocytes (mean±SD), and the yields of lymphocytes were 53% after yeast ingestion procedure. No apparent change was observed in the percentages of T and B cells after yeast ingestion. Depletion of monocytes from MNCs significantly suppressed blastogenesis of lymphocytes to the stimulation by concanavalin A, phytohemaggulutinin P or pokeweed mitogen. Incubation of MNCs with both concanavalin A and indomethacin greatly enhanced blastogenesis. 2-chloroadenosine and mitomycin C significantly suppressed blastogenic responses in cultures with MNCs. There results suggest that the monocyte-macrophage system as well as prostaglandin regulates the bovine lymphocyte blastogenic response.
