Coexpression of α9 integrin and kindlin-1 promotes DRG neurite outgrowth in vitro on tenascin-C + aggrecan. A, Neurite outgrowth of dissociated DRG neurons, mock transfected (control) or transfected with α9-eYFP and/or kindlin1–mCherry cultured on laminin or tenascin-C + aggrecan. Scale bar, 100 μm. B, C, The average neurite length of dissociated DRG neurons cultured on laminin (B), tenascin-C only, or tenascin-C + aggrecan (C) for 3 d, n = 5. D, Neurite outgrowth of DRG explants injected with AAV5–fGFP, AAV5–α9–V5, and/or AAV5–kindlin1–GFP cultured on laminin or tenascin-C + aggrecan. Scale bar, 100 μm. E, F, The average neurite length (E) and the average number of neurites per field of observation (F) of virus-injected DRG explants cultured on laminin or tenascin-C + aggrecan for 5 d, n = 5. Results were analyzed by one-way (B, E, F) or two-way (C) ANOVA and expressed as mean ± SEM. *p < 0.05, **p < 0.01, and ***p < 0.001 were statistically significant.