[Effect of female steroid hormones on expression of adhesion molecules by peripheral blood leukocytes]

The specific adhesion of cells to other cells or to extracellular matrices is a basic component of cell migration and recognition, and it underlies a lot of biologic processes including embryogenesis, tissue repair, and both immune and inflammatory responses. The aim of this study was to investigate the influence of female steroid hormones on expression of the adhesion molecules on the leukocytes. The whole blood from healthy people was incubated in a presence or an absence of progesterone (2 micrograms/ml) or 17 beta-estradiol (0.2 microgram/ml) for 4 h., and then with TNF for 18 h. The phenotype of the leukocytes was investigated by flow cytometry. Progesterone inhibited an expression of CD54 on monocytes and lymphocytes due to reducing density of these molecules on the cellular surface; 17 beta-estradiol inhibited an expression of CD54 on monocytes and CD69 molecules on monocytes and lymphocytes due to reducing density of these molecules on the cellular surface. Progesterone inhibited TNF-stimulated CD54 and CD11b expression on the granulocytes and CD69 expression on lymphocytes by reducing partly the density of these molecules on the surface of cells, and in such way it partly blocked the proinflammatory activity of this cytokine. Progesterone also reduced CD62L expression on the granulocytes by reducing an amount of a marker, positive to those cells but enhanced the effect of TNF. The data obtained evidence that female steroid hormones take part in the regulation of an expression of adhesion molecules by the leukocytes and are likely to be important in the circulation and activation of the leucocytes.