Focal transplantation–based astrocyte replacement is neuroprotective in a model of motor neuron disease

Abstract
Recent work has suggested a role for astrocyte dysfunction in the etiology of amyotrophic lateral sclerosis (ALS) caused by mutations in superoxide dismutase (SOD1). Lepore et al. show here that transplantation of astrocyte-restricted progenitors in fact improves survival of rats expressing a human ALS-associated SOD1 allele. The rescue effect required the astrocytic glutamate transporter GLT1. Cellular abnormalities in amyotrophic lateral sclerosis (ALS) are not limited to motor neurons. Astrocyte dysfunction also occurs in human ALS and transgenic rodents expressing mutant human SOD1 protein (SOD1G93A). Here we investigated focal enrichment of normal astrocytes using transplantation of lineage-restricted astrocyte precursors, called glial-restricted precursors (GRPs). We transplanted GRPs around cervical spinal cord respiratory motor neuron pools, the principal cells whose dysfunction precipitates death in ALS. GRPs survived in diseased tissue, differentiated efficiently into astrocytes and reduced microgliosis in the cervical spinal cords of SOD1G93A rats. GRPs also extended survival and disease duration, attenuated motor neuron loss and slowed declines in forelimb motor and respiratory physiological functions. Neuroprotection was mediated in part by the primary astrocyte glutamate transporter GLT1. These findings indicate the feasibility and efficacy of transplantation-based astrocyte replacement and show that targeted multisegmental cell delivery to the cervical spinal cord is a promising therapeutic strategy for slowing focal motor neuron loss associated with ALS.

This publication has 49 references indexed in Scilit: