Effect of Fibroblast Growth Factor-2 on Melanocyte Proliferation in Tissue-Engineered Skin Substitutes

Burn patients treated with tissue-engineered skin substitutes (TESs) often experience pigmentation irregularities, including hypopigmentation and pigmentation spots. These issues are thought to stem from the reduced presence of melanocytes through dilution during TES manufacturing. To address this, we hypothesized that supplementing epithelial cell cultures-primarily composed of keratinocytes but also containing melanocytes-with Fibroblast Growth Factor-2 (FGF-2), a known promoter of melanocyte proliferation, could enhance melanocyte growth. This would potentially increase their numbers in TESs and improve pigmentation outcomes. Our findings indicate that FGF-2, at an optimal dose of 0.2 nM, effectively maintains melanocyte numbers in 2D cultures and epithelial cell cultures through the first passage. Importantly, this treatment does not interfere with keratinocyte proliferation or differentiation, nor does it affect TES integrity. However, FGF-2 supplementation alone did not increase the proportion of melanocytes in epithelial cultures beyond the first passage or in TESs. In summary, while FGF-2 supports melanocyte growth in culture, its addition alone was insufficient to significantly improve TES pigmentation.