Enhancement of T-cell response to PWM by neuraminidase-treated non-T cells.

The effect of neuraminidase (from Cl. perfringens, CPN) on the human lymphocyte response to pokeweed mitogen (PWM) was studied. CPN treatment greatly increased [3H]-thymidine incorporation by human lymphocytes at lower concentrations of PWM. This enzyme acted specifically on T-cell proliferation and had no direct effect on non-T-cell proliferation. When CPN-treated non-T cells were added to autologous T cells, [3H]-thymidine incorporation was markedly enhanced at lower concentrations of PWM. However, the addition of T cells pre-treated with mitomycin C (MMC) to CPN-treated non-T cells failed to increase [3H]-thymidine incorporation in contrast to the controls. MMC-blocked, CPN-treated non-T cells significantly enhanced T-cell proliferation, whereas the effect of MMC-blocked, CPN-treated adherent cells was equal to that of the controls. These data indicate that cell-surface properties of non-T cells other than monocytes affect T-cell proliferation in some situations.