Different extracts of the Zizyphus modulate T-cell proliferation. Results are presented as mean ± S.D. The control cells without anti-CD3 antibodies had only 2000 ±120 DPM. Values differ significantly compared with anti-CD3-stimulated cells p < 0.001 (*). Each value represents the mean of six determinations. The insert shows that effects of different extracts at 20 μg/ml in the absence of anti-CD3 antibodies.