Papillary fibroblasts differentiate into reticular fibroblasts after prolonged in vitro culture
Authors
David Janson, Gaëlle Saintigny, Christian Mahé, Abdoelwaheb El Ghalbzouri
Institution
Department of Dermatology, Leiden University Medical Centre
Country
Netherlands
Year
2012
Journal
Experimental Dermatology
Abstract
The dermis can be divided in two morphologically different layers: the papillary and reticular dermis. Fibroblasts isolated from these layers behave differently when cultured in vitro. During skin aging the papillary dermis decreases in volume. Based on the functional differences in vitro, it is hypothesized that the loss of papillary fibroblasts contributes to skin aging. In this study we aimed to mimic certain aspects of skin aging by using high passage cultures of reticular and papillary fibroblasts and investigated the effect of these cells on skin morphogenesis in reconstructed human skin equivalents. Skin equivalents generated with reticular fibroblasts showed a reduced terminal differentiation and fewer proliferating basal keratinocytes. In vitro aged papillary fibroblasts had increased expression of biomarkers specific for reticular fibroblasts. The phenotype and morphology of skin equivalents generated with high passage papillary fibroblasts resembled that of reticular fibroblasts. This demonstrates that papillary fibroblasts can differentiate into reticular fibroblasts in vitro. Therefore, we hypothesize that papillary fibroblasts represent an undifferentiated phenotype, while reticular fibroblasts represent a more differentiated population. The differentiation process could be a new target for anti-skin aging strategies.