The effects of prostaglandin E and I analogues on lymphocyte stimulation

The prostacyclin analogue carbacyclin and the prostaglandin E analogues hydantoin no. 245C77 and no. 454C77 were potent inhibitors of mitogen-stimulated DNA and protein synthesis by cultured pig peripheral blood lymphocytes with ID50 concentrations between 10(-5) and 10(-8)M. These effects were comparable to those of PGE2. Strong inhibition was observed only with carbacyclin when human lymphocyte cultures were used. These results show that stable prostaglandin analogues may exhibit at least some of the activities of the naturally occurring PGE2 in this system, and support the concept that prostacyclins may also play a role in regulating immunological responses.