“Cannabinoids are known to have anti-inflammatory and immunomodulatory properties.
Cannabinoid receptor 2 (CB2) is expressed mainly on leukocytes and is the receptor implicated in mediating many of the effects of cannabinoids on immune processes.
This study tested the capacity of Δ9-tetrahydrocannabinol (Δ9-THC) and of two CB2-selective agonists to inhibit the murine Mixed Lymphocyte Reaction (MLR), an in vitro correlate of graft rejection following skin and organ transplantation. Both CB2-selective agonists and Δ9-THC significantly suppressed the MLR in a dose dependent fashion…
Together, these data support the potential of this class of compounds as useful therapies to prolong graft survival in transplant patients.
Cannabinoids were reported to have effects on immune responses as early as the 1970s, but the basis for this activity was not understood until the cannabinoid receptors were cloned
Ideally, the anatomically disparate expression of CB1 and CB2 would allow for the use of compounds selective for CB2, and thus eliminate the unwanted psychoactive effects from CB1 activation, while maintaining the anti-inflammatory and immunosuppressive properties.
CB2-selective cannabinoids have been proposed as possible candidates to block graft rejection.
The results presented in this paper show that Δ9-THC, a mixed CB1/CB2 agonist, and two CB2-selective agonists can inhibit the Mixed Lymphocyte Reaction (MLR), an in vitro correlate of organ and skin graft rejection.”