LAUSR

BACKGROUND Maternal natural killer cells (NK cells) are a prevailing leukocyte population in the uteroplacental bed. The contact interaction and/or cytokine production of these cells controls trophoblast differentiation, migration and invasion. OBJECTIVE To assess the impact of supernatants obtained during culturing of placentas from the first and third trimesters of healthy pregnancies on phenotype of trophoblast and NK cells and impact on adhesion and transmigration of NK cells through trophoblast cell layer. RESULTS We established that supernatants obtained from first trimester placentas increased the intensity of CD106, CD49e, CD95, CD49a, CD31, CD51/61, integrin β6, CD29 and VE-cadherin expression by trophoblast cells. The presence of supernatants obtained from the third trimester placentas resulted in increased intensity of CD106, CD51/61, CD49e, CD95, CD49a, CD31 and integrin β6 expression by trophoblast cells. Supernatants obtained from the first trimester placentas increased the intensity of CD11a, CD29, CD49d, CD58, KIR2DL3, CD119 and CD29 expression by NK cells. The presence of supernatants obtained from the third trimester placentas resulted in more intense KIR2DL3, CD119, CD29, CD49d, CD11a, CD29, CD49d and CD58 expression by NK cells. Migration of NK cells through trophoblast cells in the presence of first trimester placental supernatants was increased compared with the migration level in the presence of third trimester placental supernatants. This may be associated with increased expression of CD18 by NK cells. CONCLUSION Secretory products of the placenta increase receptor expression to ensure trophoblast adhesion to the matrix and increase the already sufficiently strong adhesion and migration potential of NK cells.