REVIEW ARTICLE DOI 10.1111/j.1365-2133.2007.07914.x The role of fibroblasts in tissue engineering and regeneration T. Wong, J.A. McGrath and H. Navsaria* Division of Genetics and Molecular Medicine, St John’s Institute of Dermatology, The Guy’s, King’s and St Thomas’ School of Medicine, London, U.K. *Institute of Cell and Molecular Science, Queen Mary University of London, London, U.K. Correspondence H. Navsaria. E-mail: h.navsaria@qmul.ac.uk Accepted for publication 20 December 2006 Key words burns, cell culture, dermis, skin, ulcer, wound healing Conflicts of interest None declared. Summary Fibroblasts are mesenchymal cells that can be readily cultured in the laboratory and play a significant role in epithelial–mesenchymal interactions, secreting var- ious growth factors and cytokines that have a direct effect on epidermal prolifer- ation, differentiation and formation of extracellular matrix. They have been incorporated into various tissue-engineered products such as Dermagraft Ò (Advanced BioHealing, La Jolla, CA, U.S.A.) and Apligraf Ò (Novartis, Basel, Swit- zerland) and used for a variety of clinical applications, including the treatment of burns, chronic venous ulcers and several other clinical applications in dermatol- ogy and plastic surgery. In this article we review the cell biology of dermal fibro- blasts and discuss past and current experience of the clinical use of cultured fibroblasts. Fibroblasts are a heterogeneous population of cells found in numerous tissues and are of mesenchymal origin. Fibroblasts from different anatomical sites all have similar morphology but DNA-microarray studies have demonstrated that fibroblasts in different anatomical sites have their own gene-expression profile and characteristic phenotypes, synthesizing extracellular matrix (ECM) proteins and cytokines in a site-specific man- ner. 1 Dermal fibroblasts have numerous functions, not only in synthesizing and depositing ECM components, but also prolif- eration and migration in response to chemotactic, mitogenic and modulatory cytokines, and also autocrine and paracrine interactions. 2 Culturing fibroblasts The development of techniques for culturing fibroblasts was long established prior to the discovery made in 1975 by Rheinwald and Green for culturing and expanding keratino- cytes, which require growth-arrested murine 3T3 fibroblast cells to support their proliferation. 3 Dermal fibroblasts can be extracted from skin biopsies either through enzymatic degrad- ation or by explant culture, which is particularly useful for obtaining cells from smaller specimens. The medium used for culturing fibroblasts is usually supplemented with fetal calf serum which previously raised concerns regarding transmis- sion of bovine spongiform encephalopathy (BSE). However, the serum that is currently used is obtained only from BSE- free countries. 4 Growth parameters and the characteristics of fibroblasts in culture will be influenced by passage number, age of the donor, subtype of fibroblast (reticular or papillary dermis) being cultured and anatomical site. Older donor skin fibro- blasts compared with younger skin fibroblasts tend to migrate more slowly, reach cell culture senescence earlier and have a prolonged cell population doubling time. 5 In addition, elderly donor fibroblasts are less responsive to growth factors such as platelet-derived growth factor, epidermal growth factor, dexa- methasone, insulin and transferrin in vitro. 6 Other factors that influence fibroblast behaviour in culture include vitamins, such as vitamin C, and antioxidants, includ- ing coenzyme Q10. For example, in the presence of vitamin C 100 lmol L )1 , fibroblasts produce twofold more collagen than fibroblasts cultured without, a response that is independent of the age of the fibroblasts. 6 Likewise, coenzyme Q10 supports wound healing by increasing cell proliferation and fibroblast mobility when compared with fibroblasts cultured without this antioxidant. 7 Allogeneic vs. autologous fibroblasts Fibroblasts used in tissue engineering may be allogeneic or autologous. In contrast to allogeneic cells, autologous fibro- blasts carry no risk of rejection or risk of cross-infection. However, there is often a delay in culturing autologous cells in order to obtain sufficient cell numbers, whereas allogeneic cells are cryopreserved and therefore readily available. 8,9 For permanent engraftment, autologous fibroblasts are necessary. However, allogeneic fibroblasts have been used as a biological dressing or for preconditioning of the wound bed prior to application of a permanent graft, especially when wounds are Ó 2007 The Authors Journal Compilation Ó 2007 British Association of Dermatologists • British Journal of Dermatology 2007 156, pp1149–1155 1149