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.

The conspicuous postmetamorphic coloration of fire salamanders, but not their toxicity, is affected by larval background albedo

“…This results in a higher pigmentation of the skin due to the dispersion of melanosomes into the melanophore's fingers, and the synthesis of pigments. In fire salamander larvae, all three types of chromatophores are scattered in the subepidermal collagen layer, and melanophores are regularly distributed in the epidermis (Pederzoli & Restani, ), which allows a uniform response to the background albedo. To understand how the background effect can be carried over, it is important to know that during metamorphosis the chromatophores are disposed of in a pattern resembling the adult coloration pattern (Pederzoli et al,).…”

Xanthophore Migration from the Dermis to the Epidermis and Dermal Remodeling During Salamandra salamandra salamandra (L.) Larval Development

“…Fukuzawa and Obika (20) report the expression of the cell adhesion molecules in cultures of xanthophores of Orizias latipes and X. laevis . More recently, Pederzoli and Restani (34) observed that some signal molecules such as CAMs, FN and β 1 ‐integrin are expressed in vitro by elements in the larval skin of S. s. salamandra (fibroblasts, keratinocytes and xanthophores). Fibronectin and VN are among the molecules permissive for movement and cell migration.…”