Poly I:C or IFN-alpha/beta treatment inhibits macrophage induced T cell proliferation.

IFN-alpha/beta has been previously shown to cause the suppression of various immune responses. The reason for this immunosuppression, however, remains unknown. The studies described in this report demonstrate that treatment of mice with poly I:C or partially purified IFN alpha/beta inhibited the ability of KLH pulsed macrophages to induce proliferation of KLH immune T cells. This failure to generate antigen induced proliferation was not caused by the production of prostaglandins or other suppressive molecules by IFN treated macrophages, nor did this treatment induce suppressor macrophages.