title: Dual Positive Regulation of Embryo Implantation by Endocrine and Immune Systems--Step-by-Step Maternal Recognition of the Developing Embryo.
abstract: In humans, HCG secreted from the implanting embryo stimulates progesterone production of the corpus luteum to maintain embryo implantation. Along with this endocrine system, current evidence suggests that the maternal immune system positively contributes to the embryo implantation. In mice, immune cells that have been sensitized with seminal fluid and then the developing embryo induce endometrial differentiation and promote embryo implantation. After hatching, HCG activates regulatory T and B cells through LH/HCG receptors and then stimulates uterine NK cells and monocytes through sugar chain receptors, to promote and maintain pregnancy. In accordance with the above, the intrauterine administration of HCG-treated PBMC was demonstrated to improve implantation rates in women with repeated implantation failures. These findings suggest that the maternal immune system undergoes functional changes by recognizing the developing embryos in a stepwise manner even from a pre-fertilization stage and facilitates embryo implantation in cooperation with the endocrine system.
authors.affiliation: Department of Obstetrics and Gynecology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fujiwara
authors.affiliation: Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Araki
authors.affiliation: Laboratory of Animal Breeding, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Imakawa
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, University of Toyama, Toyama, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Saito
authors.affiliation: Division of Transgenic Animal Science, Advanced Science Research Center, Kanazawa University, Kanazawa, Japan.
authors.forename: Takiko
authors.initials: T
authors.lastname: Daikoku
authors.affiliation: Advanced Fertility Center of Fuchu Nozomi, Osaka, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Shigeta
authors.affiliation: Kansai Medical University, Osaka, Japan.
authors.forename: Hideharu
authors.initials: H
authors.lastname: Kanzaki
authors.affiliation: Academia for Repro-Regenerative Medicine, Tokyo, Japan.
authors.forename: Takahide
authors.initials: T
authors.lastname: Mori
mesh_terms: D000818:Animals; D006063:Chorionic Gonadotropin / Q000276:immunology; D010064:Embryo Implantation / Q000276:immunology*; D004622:Embryo, Mammalian / Q000276:immunology*; D004703:Endocrine System / Q000276:immunology*; D005260:Female; D006801:Humans; D007986:Luteinizing Hormone / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology*; D051379:Mice; D011247:Pregnancy / Q000276:immunology*; D011974:Receptors, LH / Q000276:immunology
chemical_list: D006063:Chorionic Gonadotropin; D011974:Receptors, LH; D007986:Luteinizing Hormone
keywords: PBMC; dual control; embryo implantation; human chorionic gonadotropin; maternal recognition; sugar chain receptor