Comparative effects of bovine cytokines on cattle and bison peripheral blood mononuclear cell proliferation.

Proliferation of peripheral blood mononuclear cells (PBMC) from cattle and bison was measured following stimulation of PBMC with bovine cytokines. Bovine interleukin 1 beta (BoIL-1 beta), interleukin 2 (BoIL-2) or granulocyte-macrophage colony-stimulating factor (BoGM-CSF) at 0.1-100 U/ml were incubated for 48 h with PBMC alone or with PBMC and various mitogens. These included concanavalin A (Con A), phytohemagglutinin (PHA), pokeweed mitogen (PWM) or Escherichia coli 055:B5 lipopolysaccharide (LPS) at 10-0.1 micrograms/ml. BoIL-2 alone, but not BoIL-1 beta and BoGM-CSF alone, induced proliferation of cattle and bison PBMC in the absence of mitogens. In addition, BoIL-1 beta and BoIL-2, but not BoGM-CSF, enhanced proliferation of cattle and bison PBMC induced by mitogens. These results indicate that BoIL-1 beta and BoIL-2 stimulate cattle and bison PBMC proliferation in a similar manner, whereas BoGM-CSF does not appear capable of stimulating either cattle or bison PBMC proliferation.