INTERACTION OF CULTURED KERATINOCYTES AND FIBROBLASTS FROM HUMAN PSORIATIC AND NORMAL SKIN IN IMMUNODEFICIENT MICE

Clarification of the pathogenesis of psoriasis requires separate studi es of the epidermis, dermis, and inflammatory cells. We previously sub cutaneously transplanted a mixture of cultured human keratinocytes and fibroblasts into mice to develop cysts with human skin structures. Us ing this method, we separately cultured psoriatic and normal keratinoc ytes and fibroblasts. Four mixtures were prepared: normal keratinocyte s and normal fibroblasts (NK/NF); psoriatic keratinocytes and normal f ibroblasts (PK/NF); normal keratinocytes and psoriatic fibroblasts (NK /PF); and psoriatic keratinocytes and psoriatic fibroblasts (PK/PF). E ach mixture was transplanted into immunodeficient mice to observe form ation of cysts and histological changes. The cysts varied in structure depending on the mixture, which suggests that psoriatic keratinocytes and fibroblasts had some abnormalities. Psoriatic fibroblasts may be partially responsible for thickening of the epidermis. Cell differenti ation might have been accelerated in psoriatic keratinocytes after tra nsplantation, resulting in the loss of epidermis structures. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.