Gangliosides inhibit the proliferation of human T cells stimulated with inteleukin 4 or interleukin 2

Bovine brain gangliosides inhibited the proliferation of human T cells activated by phorbol myristate acetate (PMA) + interleukin-4 (IL-4) or PMA+interleukin-2 (IL-2). These inhibitory effects were dose and time-dependent and were significant at concentrations higher than 50μM. PMA + IL-2 stimulation was more sensitive to the inhibitory effects of gangliosides (I₅₀ = 77.2 μM) compared with PMA + IL-4 stimulation (I₅₀ = 105.9μM). Differential inhibitory effects were also examined in the panel of various gangliosides. GD1b and GT1b showed the most potent inhibitory actions in each assay, while the inhibitory effect of GD1a was somewhat less potent compared with GD1b and GT1b. GM2 and GD3 were only weakly inhibitory, whereas the inhibitory effect of GM3 was almost negligible. These findings suggest that gangliosides may play an immunomodulatory role by interfering with IL-4 or IL-2-driven proliferation of human T cells.