Taurine Chloramine Inhibits Lymphocyte Proliferation and Decreases Cytokine Production in Activated Human Leukocytes

Previously, we described the inhibition of proinflammatory mediators such as nitric oxide, tumor necrosis factor-α (TNF-α), and prostaglandin E2 by taurine chloramine (Tau-Cl) in activated rodent macrophages. We also demonstrated that Tau-Cl suppressed superoxide anion, IL-6, and IL-8 production in activated human polymorphonuclear leukocytes separated from peripheral blood. In these studies, we report the effect of Tau-Cl on lymphocyte proliferation and the production of cytokines by activated human peripheral blood mononuclear leukocytes. Adherent and nonadherent leukocytes were activated using lipopolysaccharide (LPS) and phytohemagglutinin (PHA), respectively, in the presence or absence of Tau-Cl. Tau-Cl significantly suppressed lymphocyte proliferation as measured by tritiated (3H) thymidine. Production of IL-6, IL-8, and IL-2 in PHA-activated nonadherent leukocytes was inhibited by Tau-Cl. The production of IL-1β, IL-6, and IL-8 was also decreased in LPS-activated adherent monocytes by Tau-Cl. These data demonstrate that the ability of Tau-Cl to modulate the immune response is not species specific and extends to human leukocytes.