Fig. 6

Immunomodulatory effects of GMSC-derived Schwann-like cells on pro-inflammatory (M1)/pro-regenerative (M2) macrophages in peripheral regions of crush-injured rat sciatic nerves. The functionalized nerve protectors repopulated with GMSC-derived Schwann-like cells were implanted to wrap the injured regions of rat sciatic nerves. Four weeks post-implantation, the injured nerves were harvested and cryosections were prepared for immunofluorescence studies. The cryosections were incubated with a specific mouse monoclonal antibody for rat CD68 (green color) in combination with a rabbit polyclonal antibody for arginase-1 (red color) followed by incubation with Alexa Fluor 488- and 594-conjugated secondary antibodies. Nuclei were counterstained with 4’,6-diamidino-2-phenylindole (DAPI; blue). Images were captured under a fluorescence microscope. Scale bars, 50 µm. The dashed lines separated the longitudinally sectioned nerve tissues (the lower side) and implanted nerve protector (NP) scaffolds (the upper side). b Semi-quantification of the integrated mean fluorescence intensity (MFI) for CD68 and arginase-1. Data are shown as the mean ± SD. ns, no significance; **p < 0.01; Student’s two-tailed unpaired t test. c The cryosections were incubated with a specific mouse monoclonal antibody for rat CD68 (green color) in combination with a rabbit polyclonal antibody for iNOS (red color) followed by incubation with Alexa Fluor 488- and 594-conjugated secondary antibodies. Nuclei were counterstained with (DAPI; blue). Images were captured under a fluorescence microscope. Scale bars, 50 µm. The dashed lines separated the longitudinally sectioned nerve tissues (the lower side) and implanted nerve protector (NP) scaffolds (the upper side). d Semi-quantification of the integrated mean fluorescence intensity (MFI) for CD68 and iNOS. Data are shown as the mean ± SD. ns, no significance; *p < 0.05; Student’s two-tailed unpaired t test. Abbreviations: NP, nerve protector; NP/GiSC, nerve protector repopulated with GMSC-derived Schwann-like cells (GiSC); Arg1, arginase-1; iNOS, inducible nitric oxide synthase