Cultures of skin fragments of Salamandra salamandra salamandra (L.) larvae.

Abstract

As part of a study on the pigmentary system of Salamandra salamandra salamandra (L.), we cultured skin fragments of 7-10-day-old larvae in order to examine the expression of molecules implicated in cellular adhesion and migration and in regulating cell-cell relationships. Keratinocytes, fibroblasts, Leydig cells, xanthophores, and melanophores migrated from the fragments and were observed in the outgrowth. Keratinocytes and fibroblasts organized into an epidermal layer and an underlying "dermal portion." The chromatophores were always located below the epithelial cells, often with fibroblasts. We examined by immunocytochemistry the expression of fibronectin, beta1-integrin, L-CAM, and A-CAM in the cultures. Many keratinocytes, fibroblasts, and Leydig cells expressed all the signal molecules tested. Xanthophores and melanophores were only immunoreactive to the anti-adhesion molecules antisera. Since the molecules tested are known to play a role in cell adhesion, growth, and spreading, as well as in regulating tissue differentiation and in maintaining normal tissue morphology, we may hypothesize that in Salamandra salamandra salamandra fibronectin, beta1-integrin, L-, and A-CAMs concertedly act to stabilize the architecture of the outgrowth and regulate the relationships between chromatophores and those between chromatophores and the other elements of the skin culture.