Synergistic effect of nanofat and mouse nerve-growth factor for promotion of sensory recovery in anterolateral thigh free flaps.

Anterolateral thigh (ALT) free flaps are widely used for reconstruction, but poor sensory recovery of the flap tissue can cause unsatisfactory outcomes and poor function. Adipose-derived mesenchymal stem cells (ADSCs) promote neural regeneration, but the clinical use of stem-cell therapy has been limited by lack of regulatory approval. Nanofat is an autologous product that is prepared mechanically from harvested fat. It is enriched in ADSCs and does not contain any exogenous substances. The developmental and adult neurobiology of nerve-growth factor (NGF) are well investigated, and mouse (m)NGF has been used to promote recovery following peripheral nerve injury. We investigated the promotion of nanofat and mNGF as either mono- or combined therapy on the sensory recovery of ALT free flaps. We found that nanofat and mNGF had a synergistic effect on sensory recovery that was associated with stimulation of angiogenesis and neurogenesis. Nanofat combined with mNGF was better at promoting neural regeneration and improving sensory recovery than treatment with either agent alone. The results provide a theoretical rationale for further study of the clinical use of nanofat combined with mNGF to promote the sensory recovery of ALT free flaps.