N- and E-cadherin expression in human ovarian and urogenital duct development.

OBJECTIVE: To investigate expression of N- and E-cadherin in the developing human ovary.

DESIGN: The expression of N- and E-cadherin was analyzed in 18 human fetal ovaries between 8 and 20 weeks' gestation using immunohistochemistry. Fetal human male and rat urogenital tracts were used for comparison of expression.

SETTING: Academic research institute.

PATIENT(S): Women undergoing termination of pregnancy.

INTERVENTION(S): Immunofluorescent analysis of cadherin expression.

RESULT(S): In fetal ovary, N- and E-cadherins were expressed at all gestations with overlapping but not identical patterns. Expression was associated with germ cells and adjacent somatic cells, including within newly formed primordial follicles, but neither cadherin was expressed in the somatic cell cords. The epithelia of the müllerian and wolffian ducts expressed only N- and E-cadherin, respectively, in a mutually exclusive fashion. This pattern of cadherin expression was found to be conserved between human and rat fetuses of both genders.

CONCLUSION(S): The demonstration of N- and E-cadherin expression in the human fetal ovary indicates likely roles in gonadal development from germ cell proliferation to primordial follicle formation, as well as in the development of the urogenital ducts of both genders. This is consistent with animal studies identifying cadherins as key regulators of early germ cell development.