The intensity of CD56 expression was reduced in the presence of trophoblast cells and IL-2 in non-pregnant women with recurrent miscarriage in the secretory versus the proliferative phase of the menstrual cycle.
Differential angiogenic cytokine profile of isolated CD56+ uNK cells suggested the role of uNK cells in the altered endometrial vascularity at the time of implantation, which may account for the endometrial contribution to recurrent miscarriage.
In contrast, in recurrent miscarriage tissue a sustained NK cell marker expression of both CD56 and CD16 was paralleled by a decreased expression of HLA-G. No morphological changes from the blast-like stage were apparent.