LB1767 Fibroblast growth factor-2 (FGF-2) promotes melanocyte proliferation in human epithelial cell culture

Severe burn patients in lack of donor sites for autograft harvesting can be treated with self-assembled skin substitutes (SASSs) produced in our laboratory from a small patient's skin biopsy. However, patient's pigmentation is not fully restored after SASS grafting, resulting in local pigmentation defects. These pigmentation defects are likely caused by the dilution of melanocytes in epithelial cell cultures that are used to produce the epidermal part of SASSs. Here, we hypothesized that the supplementation of the SASS culture medium with Fibroblast Growth Factor-2 (FGF-2), a melanogenic physiological growth factor, could increase melanocyte proliferation and eventually improve SASSs pigmentation. We first evaluated the role of FGF-2 in a dose-dependent manner on melanocyte proliferation using proliferation assay. We then evaluated by ELISA whether keratinocytes cultured in our culture conditions secrete FGF-2. Then, we evaluated the effect of FGF-2 on melanocyte proliferation in epithelial cell cultures containing, among others, keratinocytes and melanocytes, using flow cytometry. Our results show that FGF-2 promotes melanocyte proliferation at an optimal dose of 0,2nM. Our results also suggest that FGF-2 secretion by keratinocyte could be neglected, as they do not secrete a high dose of FGF-2. Moreover, the optimal dose of 0,2nM FGF-2 also promoted melanocyte proliferation in epithelial cell culture. These results suggest that FGF-2 could be used to improve SASS pigmentation. Future experiments will aim to evaluate pigmentation of SASSs with epithelial cells cultured in the presence of FGF-2. Hopefully, pigmentation protection will be restored when FGF-2 is added to SASS by promoting melanocyte proliferation.