Effect of compounds on phytohemagglutinin (PHA), T-cell proliferation and IL-2 production. The bar graph represents effects of various concentrations of the test compounds 1–3 after 72 h incubation with peripheral blood mononuclear cells at 37°C. Effect of compounds on T-cell proliferation response is compared with non-proliferated (+ve) and proliferated (−ve) cells (a). The bar graph represent effects of various concentrations of the test compounds (1–3) on production of IL-2 compared with (+ve) and without (−ve) PHA induced IL-2 production. Each bar represents the mean value of triplicate reading ± SD (b).