Study On The Expression Of Annexin Ⅱ In Differentiation Of Epidermal Keratinocyte

Skin lies in the interface between inner condition and outer environment of body is an important protective organ as a barrier and the epidermis is mostly made of keratinocytes. Proteinases is the important regulator in the epithelization of skin. It has been recently showed that tissue type plasminogen activator(tPA) is related to the differentiaton of keratinocytes.However,the role of annexin â…¡ ,which is recently discovered as a coreceptor protein of plasminogen(PLG) and tPA, is not clear in the differentiation of epidermal keratinocytes.In this study,the expression of annexin â…¡ was examined from two aspects: cultured keratinocytes in the condition of proliferation and differentiation;the epidermis of early, middle, late human embryo and normal adult,so as to elucidate the relationship between annexin â…¡ and the differenrtiation of epidermal keratinocytes.Methods:The expression of annexin â…¡ was detected in proliferation and differentiation of keratinocytes cultured in serum-free medium,and in early, middle, late human embryo and adult skin by ICC and IHC.Results:1. The expression of annexin â…¡ in cultured murine keratinocyte is stronger in differentiation than in proliferation , and enhances with differentiation of keratinocytes.2. The expression of annexin â…¡ in cultured human keratinocyte is stronger in differentiation than in proliferation, and enhances with differentiation of keratinocytes.3. The expression of annexin â…¡ in embryonic epidermis was significantly increased with the development of embryo, and it was mainly localized in suprabasal keratinocytes.4. The expression of annexin â…¡ in adult epidermis was much higher than that in embryonic epidermis, and it was mainly localized in the superficial, more differentiated layers of the epidermis.Conclusion:1 .The expression of annexin â…¡ in cultured human and murine keratinocyte is stronger in differentiation than in proliferation, and enhances with differentiation of keratinocytes.2.The expression of annexin â…¡ in embryonic epidermis was significantly increased with the development of embryo, and it was mainly localized in suprabasal keratinocytes.3.The expression of annexinâ…¡ in adult epidermis was much higher than that in embryonic epidermis, and it was mainly localized in the superficial, more differentiated layers of the epidermis.4. annexin â…¡ ,as the receptor of tPA, has tight relation with the differentiation of keratinocytes.