Effects of Coculture With Immune Cells on the Developmental Competence of Mouse Preimplantation Embryos in Vitro and in Utero

The aim of this study was to establish a coculture system using immune cells as well as an in vitro model for inflammatory conditioning using RAW 264.7 mouse macrophages activated by lipopolysaccharide. The direct and indirect coculture systems were applied to evaluate the influence of embryo-to-cell direct or indirect secretory molecules from the cocultured cells. Blastulation rate in vitro (94.6% vs 76.9%, P < .05) and implantation rate in utero (43.3% vs 17.6%, P < .01) were significantly increased in direct coculture with activated RAW 264.7 cells compared to control. We also found the embryotrophic effects in vitro in the indirect coculture system. Our results indicate that coculture of mouse preimplantation embryos with immune cells could improve the developmental competence in vitro and in utero. Taken together, RAW 264.7 cells secret embryotrophic molecules, and it suggests the valuable insights that immune cells could improve in vitro culture conditions of preimplantation embryos.