[The expression of activation markers on decidual lymphocytes in the first trimester of pregnancy]

To characterize the expression of activation markers CD69, IL-2R alpha, HLA-DR and transferrin receptor on decidual CD3+ and CD56+ lymphocytes, two color flow cytometry were used. Our data suggest the local activation of decidual lymphocytes. CD3+ and CD56+ cells from decidua expressed a high level of CD69 antigens. However, decidua CD3+ and CD56+ cells were different in expression of HLA-DR and IL-2R alpha. Vast majority of decidual CD3+ cells did not express IL-2R alpha and more than 50% of them were HLA-DR positive. Decidual CD56+ lymphocytes were mostly HLA-DR negative and 17% of them bore IL-2R alpha. Distinct patterns of expression of activation markers on decidual lymphocytes may be of immunobiological significance in maintenance of pregnancy.