Activation of Blood CD3 + CD56 + CD8 + T Cells during Pregnancy and Multiple Sclerosis

A striking common feature of most autoimmune diseases is their female predominance, with at least twice as common among women than men in relapsing-remitting multiple sclerosis (MS), the prevailing MS clinical form with onset at childbearing age. This fact, together with the protective effect on disease activity during pregnancy, when there are many biological changes including high levels of estrogens and progesterone, puts sex hormones under the spotlight. The role of natural killer (NK) and NKT cells in MS disease beginning and course is still to be elucidated. The uterine NK (uNK) cells are the most predominant immune population in early pregnancy, and the number and function of uNK cells infiltrating the endometrium are sex-hormones' dependent. However, there is controversy on the role of estrogen or progesterone on circulating NK (CD56 and CD56 ) and NKT cells' subsets. Here, we show a significantly increased activation of CD3 CD56 CD8 cells in pregnant MS women (MSP) compared with non-pregnant MS women (NPMS) (