EXPRESSION ASPECTS OF CD16 AND NKG2D RECEPTORS BY NK CELLS, NKT CELLS AND T LYMPHOCYTES OF PERIPHERAL BLOOD ASSOCIATED WITH FEMALE INFERTILITY

Abstract

The increasing incidence of infertility determines relevance of studying the contribution of various cellular factors, including immune cells, to its pathogenesis. The changes are described in NK cell activation in decidua and peripheral blood during infertility, as well as in representation of NKT cells and T lymphocytes in uterus at miscarriage (MC). NK cells and NKT cells are characterized by expression of activating receptor NKG2D and receptor for immunoglobulin G Fc-binding CD16. Distinct populations of T lymphocytes express NKG2D. The aim was to analyze the expression of CD16 and NKG2D by NK cells, NKT cells and NKG2D by peripheral blood T lymphocytes in women with infertility. We examined 60 women with infertility. The control group consisted of healthy non-pregnant fertile women (n=17). Mononuclear cells were obtained from peripheral blood and treated with monoclonal antibodies to CD45, CD14, CD3, CD56, CD16, NKG2D. We showed that in patients with primary infertility, NKG2D receptor expression intensity by peripheral blood NKT cells was lower than in healthy non-pregnant fertile women. The established difference may be due to absence of an embryo implantation in medical history at primary infertility and accordingly absence of the influence of cytokine and cellular microenvironment specific for first trimester of pregnancy. In patients with secondary infertility and MC, relative number of CD16+ NK cells and CD16+NKG2D- NK cells in peripheral blood was reduced compared to this parameter in women with secondary infertility without a history of MC. Relative numbers of CD16+ NK cells and CD16+NKG2D- NK cells in peripheral blood were also reduced in patients with secondary infertility and MC compared to patients with primary infertility and to healthy non-pregnant fertile women. CD16 expression intensity of NK cells was shown to be reduced in subgroup of women with secondary infertility and a history of MC compared to control group and to women with secondary infertility without a history of MC. No differences in NKG2D expression by T lymphocytes associated with infertility were established. Reduced CD16 expression by NK cells of women with secondary infertility and MC may reflect the impaired functional differentiation of NK cells associated with this pathology.

Keywords

• nk cells
• nkt cells
• t lymphocytes
• cd16
• nkg2d
• peripheral blood
• infertility.