Cannabinoid receptors and the cytokine network.

Splenocyte cultures from BALB/c mice were treated with THC and mitogen and shown to produce less Th1 cytokine, IFN gamma, and more Th2 cytokines, IL-4 and IL-10. This suggested that drug treatment caused a shift in the development of Th1 and Th2 cells. In studies designed to look at molecular mechanisms, the CBI antagonist, SR141716A, did not attenuate the THC enhancement of IL-4 production, but pertussis toxin attenuated the drug effect and the CB2 agonist, JWH-051, increased IL-4 production similar to THC. These results suggest that cannabinoids may increase Th2 development and IL-4 production in cultured immune cells through the activity of the CB2 receptor subtype. Studies are currently in progress to further define the molecular and cellular mechanisms involved.