in vivo human embryonic spinal cord atlas validates stem cell-derived human dorsal interneurons and reveals ASD spinal signatures [day27NMP_scRNAseq]

We are working towards restoring sensation by developing directed differentiation protocols to generate dorsal spinal interneurons (dIs; dI1-dI6) from human embryonic stem cells (hESCs). Here, we present an improved method that produces human dIs via a neuromesodermal progenitor state, the physiological intermediate for spinal cord development.

We show that retinoic acid (RA), bone morphogenetic protein 4 (BMP4) and growth differentiation factor (GDF) 11 direct dI identity, while GDF11 and extended time in culture promotes posterior spinal identities. Together, these protocols generate the full complement of dorsal subtypes along the entire anterior-posterior axis of the spinal cord. To benchmark in vitro-derived dIs, we constructed a single-cell RNA-Seq atlas of the human embryonic spinal cord and used it to show that hESC-derived dIs closely match their endogenous counterparts.