FIG. 4.

Stimulation of human and bovine PBMCs with rSPEGGs. PBMCs were isolated from bovine (A) and human (B) blood samples and incubated with various concentrations of rSPEGGs. After 2 days, 0.1 μCi of [³H]thymidine was added, and cells were incubated for a further 18 h before being harvested and counted for the thymidine uptake with a beta counter. These experiments are representative of four independent experiments. In panel C, bovine PBMCs (solid bars) and T-cell-depleted bovine PBMCs (open bars) were stimulated with 1 μg/ml of SPEGGs and SPE-G for 2 days and the mitogenic response was measured as described in Materials and Methods. Serial dilution was performed without SPEGG and used as a negative control (marked as “cell”). cont, control.