POU4F2 and infection: At 3–4 weeks following infection of the adult retina by GFAP-Math5-Brn3b-tdTomato AAVs, numerous tdTomato-immunoreactive RGCs were observed on the vitreous surface of the retina, which extended axons that were fasciculated into many thick axon bundles immunoreactive for Tuj1 (Figures 5A–E).