In vivo cell retention of transplanted BMSCs-laden SFN-LP hydrogel system: (a) In vivo bioluminescence imaging of the Luc+/GFP+ BMSCs at wound area when free cells (A), cell-laden SFN hydrogels (B) and cell-laden SFN-LP hydrogels (C) were injected for different times.The inner diameter of silicone splints is 1.5 cm; (b) Quantification of total flux in the different groups. Hydrogels significantly improved the retention of BMSCs at wound sites. Data presented as mean ± SD, n = 6, the error bars indicate the SD. P-values are calculated using two-way ANOVA with Turkey’s multiple comparison tests, statistically significant *P < 0.05, *** P < 0.001. NS means no statistic difference.