Cross-talk Between Murine Trophoblast and Innate Immune Components in an in vitro set up.

BLOIS, SM; GARCIA, M; TOMETTEN, M; ORSAL, AS; BARRIENTOS, G; ARCK, PC

Congreso; 4th European Congress of Reproductive Immunology; 2006

A sophisticated balance of innate and adadptive immune responses at the feto-maternal interface promotes tolerance of trophoblast cells carrying paternally derived antigens (Ag). Likely, such regulatory functions involve uterine dendritic cells (DC) as well as NK cells. Recently, the existence of a NK:DC cross talk could be revealed in various experimental settings, ranging from cooperative stimulation to cell lysis. However, little is know about NK DC cross talk at the feto-maternal interface. Here, we deliver first evidence that fetal Ag derived from low and high abortion murine matings affect proliferation of mature (NK1.1+) decidual NK cells in vitro, whereas proliferation of DC, identified by CD11c+ , is not affected.We further reveal that, in the absence of NK1.1+ cells within the decidual cell network, production of IL-12 is increased in the presence of paternal Ag from abortion-prone matings in vitro. We further show that decidual IL-12 is predominantely derived from uterine CD11c+ cells. Based on these finding, we conclude that the elimination of mature uterine DC by NK cells could be a negative feedback mechanism involved in terminating ongoing immune responses against fetal Ag and consequently limits pregnancy immunopathologies.