Hans Keirstead

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Demyelination contributes to loss of function after spinal cord injury, and thus a potential therapeutic strategy involves replacing myelin-forming cells. Here, we show that transplantation of human embryonic stem cell (hESC)-derived oligodendrocyte progenitor cells (OPCs) into adult rat spinal cord injuries enhances remyelination and promotes improvement(More)
Human embryonic stem cells (hESCs) demonstrate remarkable proliferative and developmental capacity. Clinical interest arises from their ability to provide an apparently unlimited cell supply for transplantation, and from the hope that they can be directed to desirable phenotypes in high purity. Here we present for the first time a method for obtaining(More)
Elucidation of the response of oligodendrocyte progenitor cell populations to demyelination in the adult central nervous system (CNS) is critical to understanding why remyelination fails in multiple sclerosis. Using the anti-NG2 monoclonal antibody to identify oligodendrocyte progenitor cells, we have documented their response to antibody-induced(More)
Genomic stability is critical for the clinical use of human embryonic and induced pluripotent stem cells. We performed high-resolution SNP (single-nucleotide polymorphism) analysis on 186 pluripotent and 119 nonpluripotent samples. We report a higher frequency of subchromosomal copy number variations in pluripotent samples compared to nonpluripotent(More)
Human pluripotent stem cells (hPSCs) are potential sources of cells for modeling disease and development, drug discovery, and regenerative medicine. However, it is important to identify factors that may impact the utility of hPSCs for these applications. In an unbiased analysis of 205 hPSC and 130 somatic samples, we identified hPSC-specific epigenetic and(More)
The failure of regeneration of severed axons in the adult mammalian central nervous system is thought to be due partly to the presence of endogenous inhibitors of axon regeneration. The nogo gene encodes three proteins (Nogo-A, -B, and -C) that have been proposed to contribute to this inhibition. To determine whether deletion of nogo enhances regenerative(More)
Differential methylation between the two alleles of a gene has been observed in imprinted regions, where the methylation of one allele occurs on a parent-of-origin basis, the inactive X-chromosome in females, and at those loci whose methylation is driven by genetic variants. We have extensively characterized imprinted methylation in a substantial range of(More)
In an embryonic chicken, transection of the thoracic spinal cord prior to embryonic day (E) 13 (of the 21-day developmental period) results in complete neuroanatomical repair and functional locomotor recovery. Conversely, repair rapidly diminishes following a transection on E13-E14 and is nonexistent after an E15 transection. The myelination of fiber tracts(More)
Preceding the development of therapeutic strategies for spinal cord injury is an identification of those pathological processes that might serve as therapeutic targets. Although demyelination has been documented as a secondary degenerative component of spinal cord injury in several species including humans, the extent of demyelination and its functional(More)
Neurogenesis has been described in various regions of the CNS throughout life. We examined the extent of natural cell division and replacement from 7 weeks to 7 months after cervical spinal cord injury in four adult rhesus monkeys. Bromodeoxyuridine (BrdU) injections revealed an increase of >80-fold in the number of newly divided cells in the primate spinal(More)