A novel, alternatively activated neutrophil subset promotes CNS neuron survival and axon regeneration in vivo

Transected axons typically fail to regenerate in the central nervous system, resulting in chronic neurological disability in individuals with traumatic brain or spinal cord injury, multiple sclerosis, and stroke, as well as glaucoma and ischemic reperfusion injury of the eye. Although neuroinflammation is often depicted as detrimental, there is growing evidence that alternatively activated, reparative leukocyte subsets and their products can be deployed to improve neurological outcomes. In the current study we identify a unique granulocyte subset, with characteristics of an immature neutrophil, that has neuroprotective properties and drives CNS axon regeneration in vivo, in part via secretion of a cocktail of growth factors. This pro-regenerative neutrophil promotes repair in the optic nerve and spinal cord, demonstrating its relevance across CNS compartments and neuronal populations. Our findings could ultimately lead to the development of novel immunotherapies that reverse CNS damage and restore lost neurological function across a spectrum of diseases. Overall design: 10x Genomics single cell sequencjavascript:validateForm()ing on Ly6G +ve neutrophils isolated from the vitreos of mice subjected to i.o zymosan injection and aCXCR2/NRS antisera treatment.