This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Nakayama, J. Articles by Fukuda, M. N. Search for Related Content PubMed PubMed Citation Articles by Nakayama, J. Articles by Fukuda, M. N.

(American Journal of Pathology. 2003;163:2211-2219.)
© 2003 American Society for Investigative Pathology

Implantation-Dependent Expression of Trophinin by Maternal Fallopian Tube Epithelia during Tubal Pregnancies

Possible Role of Human Chorionic Gonadotrophin on Ectopic Pregnancy

Jun Nakayama^*, Daisuke Aoki, Tomoaki Suga, Tomoya O. Akama, Satoshi Ishizone^¶, Hirohito Yamaguchi^||, Kazuhiko Imakawa^||, Daita Nadano^**, Asgerally T. Fazleabas, Tsutomu Katsuyama, Shiro Nozawa and Michiko N. Fukuda

From the Departments of Pathology,^* Internal Medicine, Surgery,^¶ and Laboratory Medicine, Shinshu University School of Medicine, Matsumoto, Japan; the Department of Obstetrics and Gynecology, School of Medicine, Keio University, Tokyo, Japan; the Laboratory of Animal Breeding,|| University of Tokyo, Tokyo, Japan; the Department of Applied Molecular Biosciences,^** Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan; the Department of Obstetrics and Gynecology, University of Illinois, Chicago, Illinois; and the Glycobiology Program, The Burnham Institute, La Jolla, California

Trophinin, tastin, and bystin have been identified as molecules potentially involved in human embryo implantation. Both trophoblasts and endometrial epithelial cells express trophinin, which mediates apical cell adhesion through homophilic trophinin-trophinin binding. We hypothesized that trophinin’s function in embryo implantation is unique to humans and investigated the expression of trophinin, tastin, and bystin in ectopic pregnancy, a condition unique to humans. In tubal pregnancies, high levels of all three were found in both trophoblasts and fallopian tubal epithelia. Trophinin expression in maternal cells was particularly high in the area adjacent to the trophoblasts, whereas trophinin was barely detectable in intact fallopian tubes from women with in utero pregnancies or without pregnancies. When explants of intact fallopian tube were incubated with the human chorionic gonadotrophin (hCG), trophinin expression was enhanced in epithelial cells. Since the trophectoderm of the human blastocyst secretes hCG before and after implantation, these results suggest that hCG from the human embryo induces trophinin expression by maternal cells. As both ß-subunit of hCG and trophinin genes have diverged in mammals, the present study suggests a unique role of hCG and trophinin in human embryo implantation, including the pathogenesis of ectopic pregnancy.

This article has been cited by other articles:

				A.W. Horne, W.C. Duncan, A.E. King, S. Burgess, P.C. Lourenco, P. Cornes, P. Ghazal, A.R. Williams, L. Udby, and H.O.D. Critchley Endometrial cysteine-rich secretory protein 3 is inhibited by human chorionic gonadotrophin, and is increased in the decidua of tubal ectopic pregnancy Mol. Hum. Reprod., May 1, 2009; 15(5): 287 - 294. [Abstract] [Full Text] [PDF]

				K. Sugihara, D. Sugiyama, J. Byrne, D. P. Wolf, K. P. Lowitz, Y. Kobayashi, M. Kabir-Salmani, D. Nadano, D. Aoki, S. Nozawa, et al. Trophoblast cell activation by trophinin ligation is implicated in human embryo implantation PNAS, March 6, 2007; 104(10): 3799 - 3804. [Abstract] [Full Text] [PDF]

				S. Hatakeyama, C. Ohyama, S. Minagawa, T. Inoue, H. Kakinuma, A. Kyan, Y. Arai, T. Suga, J. Nakayama, T. Kato, et al. Functional Correlation of Trophinin Expression with the Malignancy of Testicular Germ Cell Tumor Cancer Res., June 15, 2004; 64(12): 4257 - 4262. [Abstract] [Full Text] [PDF]