The staining methods were previously described (Zhu et al., 2007 (link), 2009 (link), 2013 (link); Peng et al., 2012 (link)). The antibodies for staining were purchased from the following sources: IL-17c antibody (mouse monoclonal, R&D Systems); IL-17RE antibody (rabbit polyclonal, Sigma-Aldrich); IL-17RA antibody (rabbit monoclonal, LifeSpanBioSciences); NCAM antibody (mouse monoclonal, BD); PGP9.5 (Abcam); NF200 antibody (rabbit polyclonal, Sigma-Aldrich); Peripherin antibody (rabbit and mouse, Sigma-Aldrich); cleaved caspase 3 antibody (rabbit polyclonal, Cell Signaling Technology).