Figure 2.

LV50 decreases cell viability and inhibits cell proliferation. Jurkat, CEM, and PBL cells were cultured with different concentrations of LV50 for 24, 48, and 72 h. The number of viable cells was determined by Trypan Blue exclusion test. (A, left panel) Jurkat cells, data are reported as the mean ± SD among ten independent experiments. Statistical analysis indicated: **** p < 0.0001 versus vehicle. (A, right panel) Jurkat cells were pretreated with selective antagonist for CB2R (SR144528, 1 μM), exposed to LV50 for 72 h and then analyzed for cell viability. Statistical analysis indicated: **** p < 0.0001 versus vehicle; **** p < 0.0001 versus pretreated with SR144528. (B, left panel) CEM cells, data are reported as the mean ± SD among ten independent experiments. Statistical analysis indicated: **** p < 0.0001 versus vehicle. (B, right panel) CEM cells were pretreated with selective antagonist for CB2R (SR144528, 1 μM), exposed to LV50 for 72 h and then analyzed for cell viability. Statistical analysis indicated: **** p < 0.0001 versus vehicle; **** p < 0.0001 versus pretreated with SR144528. (C) PBL cells, data are reported as the mean ± SD among ten independent experiments. Statistical analysis indicated: LV50 10 μM versus vehicle NS (not significant). (D, left panel) Cell proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in Jurkat cells. The results represent the mean ± SD of five independent experiments performed in triplicate and represent cell viability as a percentage of untreated control cells. Statistical analysis indicated: ** p < 0.01 versus vehicle; *** p < 0.001 versus vehicle. (D, right panel) Jurkat cells were pretreated with selective antagonist for CB2R (SR144528, 1 μM), exposed to LV50 for 72 h and then analyzed for proliferation. Statistical analysis indicated: **** p < 0.0001 versus vehicle; **** p < 0.0001 versus pretreated with SR144528.