[Effect of tissue-type plasminogen activator on differentiation of keratinocyte in the human embryonic epiderm]

To explore the regulating roles of tissue-type plasminogen activator (tPA) in the differentiation of keratinocyte in the human epidermis.

Immunocytochemistry and in situ hybridization were employed to study tPA expression quantitatively and qualitatively in early, middle and late human embryos skin respectively.

(1) The expression of tPA was significantly increased in the development of embryonic period, with the highest level in the middle embryonic phase, but the transcription of tPA still kept rather high level in the late human embryonic phase. (2) tPA was mainly localized in the superficial, more differentiated layers of the epidermis. (3) tPA was localized in peripheral cytoplasm of keratinocyte.

tPA participates the regulation of the keratinocyte differentiation.