Immunohistochemical localization of epidermal growth factor in human endometrium, decidua, and placenta

Epidermal growth factor (EGF) was localized immunohistochemically in human endometrium throughout the menstrual cycle, in gestational decidua, and in first, second, and third trimester placenta using two polyclonal antihuman EGF antisera. In proliferative phase endometrium, moderate EGF immunostaining was localized to the cytoplasm of stromal cells, with absent to light staining of glandular epithelium. In the secretory phase, EGF immunostaining was intense and localized predominantly to stromal cells, particularly those surrounding spiral arterioles. There was absent to light EGF immunostaining within epithelial cells; however, there was no staining of subnuclear vacuoles. In addition, the luminal surface of exhausted secretory glands demonstrated moderate EGF immunostaining. In gestational decidua, EGF immunostaining was light to moderate in the stromal cells, but was intense in the surface epithelium. Intense EGF immunostaining was noted in the syncytiotrophoblast layer of first trimester placenta, with light to moderate staining of the cytotrophoblast. Immunostaining decreased in both layers of trophoblast as pregnancy progressed. Immunoreactive EGF is found in endometrium and trophoblast and may have a physiological role in endometrial and placental function.