INTERLEUKIN-1-BETA, HUMAN-LEUKOCYTE ANTIGEN HLA-DR-ALPHA, AND TRANSFORMING GROWTH-FACTOR-BETA EXPRESSION IN ENDOMETRIUM, PLACENTA, AND PLACENTAL MEMBRANES

Maternal immune recognition of the fetal semiallograft appears to be necessary and beneficial for fetal survival and growth. Interleukin-1β and human leukocyte antigen HLA-DR are important for foreign antigen recognition by the immune system, whereas transforming growth factor-β inhibits many of the immunostimulatory properties of interleukin-1β. In this study we found that first-trimester decidua and term placental membranes expressed significantly higher levels of interleukin-1β, interleukin-1β messenger ribonucleic acid, and human leukocyte antigen HLA-DRα messenger ribonucleic acid than proliferative and secretory endometrium. Fetal placenta had little, if any, interleukin-1β, interleukin-1β messenger ribonucleic acid, or human leukocyte antigen HLA-DRα messenger ribonucleic acid expression. All tissues found at the maternal-fetal interface, including first-trimester decidua, placenta, and placental membranes, contained transforming growth factor-β and expressed transforming growth factor-β1 messenger ribonucleic acid. On the basis of these findings, we suggest that the increase in decidual interleukin-1β and human leukocyte antigen HLA-DRα during pregnancy may be involved in maternal recognition of the fetal semiallograft and that transforming growth factor-β production may regulate the local maternal immune response and prevent rejection of the fetus. © 1990.