a, AAV in cortical slice ex vivo taken from a 14-year-old rhesus macaque. b, CAP-Mac is more efficient at transducing neurons in gray matter of cortex. c, Quantification demonstrates that CAP-Mac-delivered transgene is better at producing RNA but not DNA compared to AAV9-delivered transgene. Two-tailed Welch’s t-test (*P<0.05). d-f, AAV in adult rhesus macaques in vivo. d, Recovered DNA from adult macaque administered with 8-capsid pool. One-way ANOVA using Tamhane’s T2 correction tested against AAV9 enrichment. (****P<0.0001). e, We injected 1 x 1013 vg of CAP-Mac packaging a CAG-eGFP into one 17-year-old rhesus macaque to assess CAP-Mac protein expression. g, CAP-Mac-mediated eGFP expression visualized after amplification with GFP antibody. Mean ± s.e.m. shown.