Fig. 1.

Glial progenitor cell sources, phenotypes and clinical targets. GPCs may be directly sorted from tissue or generated from either hESCs or hiPSCs and then immunoselected based on their expression of either the A2B5 epitope or CD140a/PDGFαR. The CD140a phenotype includes all potential oligodendrocytes, whereas the tetraspanin CD9 identifies a pro-oligodendrocytic fraction (10). The choice of tissue-, hESC-, or iPSC-derived GPCs depends on whether allogeneic or autologous grafts are desired. Whereas autologous grafts of iPSC-derived GPCs might obviate the need for immunosuppression, their generation may take months, and their use in the hereditary leukodystrophies would first require correction of the underlying genetic disorder in the donor cell pool. At present, such genetic disorders of myelin may be better approached with allografted tissue- or hESC-derived GPCs.