Assessment of Wound Bed Delivery of Galectin-3 to Modulate Macrophage Polarization, Re-epithelialization and Collagen Synthesis in a Murine Model of Excisional Skin Healing

Chronic wounds remain trapped in a pro-inflammatory state, with strategies targeted at inducing re-epithelialization and the proliferative phase of healing desirable. A member of the lectin family, galectin-3 is implicated in regulation of macrophage phenotype and epithelial migration. We investigated if local delivery of galectin-3 enhanced skin healing in a full thickness excisional C57BL/6 mouse model. An electrospun gelatin scaffold loaded with galectin-3 was developed and compared to topical delivery of galectin-3. Electrospun gelatin/galectin-3 scaffolds had an average fiber diameter of 200 nm, with 83% scaffold porosity approximately and am average pore diameter of 1.15 μm. The developed scaffolds supported dermal fibroblasts adhesion, matrix deposition and proliferation in vitro. In vivo treatment of 6 mm full thickness excisional wounds with gelatin/galectin-3 scaffolds did not influence wound closure, re-epithelialization or macrophage phenotypes, but increased collagen synthesis. In comparison, topical delivery of galectin-3 [6.7 µg/ml] significantly increased arginase-I cell density at day 7 versus untreated and gelatin/galectin-3 scaffolds (p<0.05). Preliminary assessment of increasing the concentration of topical galectin-3 demonstrated that at day 7, galectin-3 [12.5 µg/ml] significantly increased both epithelial migration and collagen content in a concentration dependent manner. In conclusion, local delivery of galectin 3 shows potential efficacy in modulating skin healing in a concentration dependent manner.