Inhibition of lymphocyte proliferation by free fatty acids. I. Differential effects on mouse B and T lymphocytes.

Saturated and unsaturated long-chain fatty acids were compared for their effects on mitogen-induced DNA synthesis in mouse B and T lymphocytes. At high concentrations (100-120 microM) all of the fatty acids tested were inhibitory to some extent, while at lower concentrations (20-60 microM) only the saturated fatty acids suppressed DNA synthesis. The inhibitory effects of the saturated acids could be reversed by the simultaneous addition of either a cis- or a trans-monounsaturated or a cis,cis-diunsaturated fatty acid. Compared to T cells stimulated with either phytohaemagglutinin or concanavalin A, B cells stimulated with either lipopolysaccharide or 8-bromoguanosine were considerably less susceptible to the inhibitory effects of the saturated fatty acids. These results demonstrate that free fatty acids may be useful tools for delineating the metabolic events involved in B cell and T cell activation.