Expression of protein kinase C isozyme in epidermal Langerhans cells of the mouse.

Protein kinase C (PKC) is encoded by a complex of a gene family, and its multiple isozymes are expressed in various mammalian tissues. We examined whether PKC is expressed in epidermal Langerhans cells (LC) of the mouse by using monoclonal antibodies specific to PKC I, PKC II, and PKC III isozymes (respective products of PKC genes gamma, beta, and alpha). Immunohistochemical and immunoblotting studies revealed that LC of adult C57BL/6 mice express PKC II, while PKC I and PKC III were not detected. In keratinocytes, none of the isozymes were detected. These results suggest that PKC II is a novel marker of LC and that it possibly plays a regulatory role in epidermal LC of the mouse in vivo.