Immuno-Enhancing Effects of Ricin

Abstract

The effect of ricin on human peripheral blood mononuclear cells (PBMC) was tested in vitro. At low concentrations (10–³ and 10⁻-¹ μg/ml), rich potentiated the effect of lipopolysaccharide to induce interleukin 1 (IL-1). Ricin was not mitogenic or co-mitogenic with phytohaemagglutinin or concanavalin A in PBMC cultures at low concentrations (<10⁻-¹ μg/ml). Higher concentrations of ricin (>10⁻-³ μg/ml) inhibited production of IL-1 by PBMC and the mitogen-driven proliferation of PBMC cultures.