Regulation of lymphocyte activation by PGE2 in multiple sclerosis

The immunoregulatory action of prostaglandin E2 (PGE2) was examined in two independent lymphocyte activation assays of peripheral blood lymphocytes obtained from multiple sclerosis (MS) patients and normal controls. Phytohaemagglutinin (PHA)-mediated stimulation of lymphoblast transformation and leucocyte migration inhibition factor (LIF) release were both inhibited by PGE2 in a dose-dependent manner. Sixteen patients with MS were studied as a single clinical group and their PHA-stimulated lymphocytes shown to respond essentially normally to PGE2. Four patients in relapse exhibited diminished responsiveness in both assays, but only at a supraphysiological concentration of PGE2. Thus, unresponsiveness to immunoregulatory prostaglandins is unlikely to be a major contribution to the immunopathogenesis of MS.