ASCL1 induces neurogenesis in human Muller glia
In mammals, loss of retinal cells due to disease or trauma is an irreversible process which can lead to blindness. Interestingly, regeneration of retinal neurons is a well-established process in some non-mammalian vertebrates and is driven by the Muller glia (MG), which are able to re-enter the cell cycle and reprogram into neurogenic progenitors upon retinal injury or disease. Progress has been made to restore this mechanism in mammals to promote retinal regeneration: MG can be stimulated to generate new neurons in vivo in the adult mouse retina after the over-expression of the pro-neural transcription factor Ascl1. In this study, we applied the same strategy to reprogram human MG derived from fetal retina and retinal organoids into neurons. Combining scRNA-seq, scATAC-seq, Immunofluorescence, and electrophysiology we demonstrate that human MG can be reprogrammed into neurogenic cells in vitro. Overall design: To study the development of the Muller glial cell over time in the human retina, fetal retinal tissues from a D59 and D76 samples were processed with the Multiome kit (snRNA-seq and snATAC-seq). For the D76 sample, the central part of the retina was isolated from the periphery and samples were further processed individually. We also include in this submission scRNA-seq data from the over expression of ASCL1 in human fetal Muller glia cultures. For the reprogramming paradigme we used Muller glia in vitro cultures derived from Retinal organoids and Retinospheres were generated. Cultures were then infected with a lentivirus driving the expression of the pro-neural transcription factor ASCL1 prior to processing with the 10x genomics platform.