Is the modulatory effect of pregnancy in multiple sclerosis associated with changes in blood apoptotic molecules?

Objective: We examined whether the modulatory effect of pregnancy on multiple sclerosis (MS) is associated with changes in the apoptotic molecules in sera.

Subjects And Methods: The serum levels of tumor necrosis factor-related apoptosis-inducing ligand (sTRAIL), sFas, Fas ligand (sFasL) and macrophage migration inhibitory factor were analyzed from 19 MS patients and 14 controls during late pregnancy and post-partum. The obtained results were related to disease activity and the progression of MS.

Results: Disease activity decreased during pregnancy. The levels of sTRAIL and sFasL increased from late pregnancy to post-partum situation in both MS patients and controls, but in MS patients the changes in the levels of sTRAIL from late pregnancy to post-partum were smaller than in controls.

Conclusions: Post-partum upregulation of TRAIL and FasL seems to be caused by physiologic reactivation of the mother's immune system after pregnancy. An increased risk of relapses in MS post-partum may be associated with changes in the immunomodulatory potential of these apoptotic molecules.