Effect of delta9-tetrahydrocannabinol on in vitro sensitization of mouse splenic lymphocytes.

The effects of delta9-tetrahydrocannabinol (delta9-THC) on the immune response of murine cells sensitized in vitro was determined using a plaque-forming cell (PFC) assay. Splenic lymphocytes from mice injected with delta9-THC showed a depressed immunologic response when compared with cells from control animals which were identically sensitized in vitro with sheep erythrocytes (SRBC). The direct addition of delta9-THC to the culture media altered the immunological response as demonstrated by a reduction in the number of PFC.