Expression of canine Kdap in normal, hyperplastic and neoplastic epidermis.

Keratinocyte differentiation-associated protein, Kdap, is a recently identified small secretory protein that may act as a soluble regulator for the cornification and/or desquamation of keratinocytes. To clarify the role of Kdap in the terminal differentiation of keratinocytes, detailed in situ localisation of Kdap was studied using canine skin with normal, hyperplastic and neoplastic epidermis. In normal canine trunk skin, Kdap was expressed by granular keratinocytes, with polarity to the apical side of the cells, suggesting that canine Kdap is present in lamellar granules, as in humans.