Changes in keratin expression of human vaginal epithelium during different female generation phases. Polyclonal...

Distinct expression patterns of keratins reflect different epithelial prototypes and different epithelial differentiation pathways. In order to get evidence of the expression of keratins in a hormone-dependent tissue in man, we investigated 70 epithelial tissue specimens by means of SDS-gel electrophoresis and immunoblot. Every tissue probe belonged to different generation phases such as sexual maturity, climacteric and postmenopausal period and pregnancy. Keratins 1(avb), 4(avb), 5(avb), 10(avb), 13, 14 were detected regularly whereas keratins 6, 16, and 19 are expressed irregularly. During all generation phases, with the exception of pregnancy, the keratins 1 and 10, associated with the epidermal differentiation, and keratins 4 and 13, associated with the differentiation to a non-keratinizing stratified epithelium, are synthesized simultaneously. However in pregnancy, i.e. pregnancy at term of delivery, only K4/K13 are expressed, while K1/K10 are below the detection limit. In terms of keratin expression vaginal epithelium represents a mosaic of differentiation. Only in pregnancy the 'pure' type of a nonkeratinizing epithelium is seen, apparently as a result of the high concentration of estrogens.