FIGURE 4.

Effects of cannabinoids on the anti-CD3/anti-CD28-induced phosphorylation of Lck, Zap 70, LAT, and MAPK. A, naive Jurkat cells expressing CB2 (above) and IL-4-stimulated Jurkat cells expressing CB1 and CB2 (below) received a single dose of THC (500 nm) and were incubated with the drug for various times according to the scheme below the gels. Then the cells received fresh medium, were activated with anti-CD3/anti-CD28 for 2 min as indicated, and were lysed. The blots were probed for phospho-specific proteins (P-) and actin as shown. Representative Western blot experiments are depicted. B, quantification of Western blot signals of at least two individual experiments performed in duplicate normalized to actin. All of the samples are compared with the anti-CD3/anti-CD28 activated samples shown in group 2, which were set to 100%. Secondary comparisons are indicated by brackets. *, p < 0.05; **, p < 0.01; ***, p < 0.001.