title: Human trophoblast and endometrial interactions in vitro.
abstract: Human trophoblast and endometrial cell interaction was studied by using tissue culture techniques as an in vitro model experiment on ovum implantation. Mixed cultures of trophoblast of the early gestational stage and endometrial cells of the mid-secretory phase were performed, and the interactions between these cells were observed by using a phase contrast microscope and microcinematographs. Trophoblast cells showed marked affinity and firm attachment to endometrial cells, and their outgrowth and maintenance were significantly better in the mixed cultures with endometrial cells than in the cultures of trophoblast alone. These characteristic interactions appeared to be closely related to attachment and anchoring of trophoblast to endometrium, and suggested the supportive and nutritive roles of endometrial cells in trophoblast development in the process of implantation. Trophoblast cells showed active cell locomotion, pinocytosis, and phagocytosis. Aggressive action on epithelial endometrial cells observed in the cinematographs seemed to be suggestive of the cytolytic activity of trophoblast cells. Trophoblast cells invaded endometrial cell sheet in the same manner as malignant tumor cells in vivo. Outgrowth and invasion of trophoblast cells were finally arrested by transformed endometrial cells similar to decidual cells morphologically. These results demonstrated the in vitro decidualization of endometrial cells and suggested their control action against trophoblast invasion.
mesh_terms: D002448:Cell Adhesion; D002478:Cells, Cultured; D046508:Culture Techniques; D004717:Endometrium / Q000502:physiology*; D005260:Female; D006801:Humans; D011247:Pregnancy; D014327:Trophoblasts / Q000502:physiology*