Abstract
The acute spinal cord injury (SCI) lesion environment is multicellular in nature, containing cells that facilitate both inflammatory and scar forming responses to injury. Our limited understanding for the mechanisms that drive these pathologies has hindered the development of successful therapeutic interventions for promoting wound healing and circumventing regenerative failure. Among the many pathologies present after contusive SCI, myeloid cell infiltration and activation is one the most influential in terms of wound healing progression. The myeloid cell population present at the injury site includes both resident microglia and peripherally derived macrophages that migrate into the lesion from the disrupted vasculature. Both populations are highly complex and undergo rapid state changes based on molecular ques from the pathological environment. While many groups have worked to characterize these states, their functional identity is still up for debate. This lack of consensus calls for additional investigation into the functional identities of post-injury myeloid cells, which will allow us to gain a more detailed understanding of their role in wound healing pathology. To gain a more detailed understanding of the heterogeneity that exists within myeloid cell populations at the injury site, this study uses single-cell RNA sequencing to produce a transcriptomic profile of the acute injury environment at several hallmark stages of mouse SCI. Overall, the data from this project provides the field with a detailed account of myeloid cell diversity and function within the acute SCI timeframe, allowing us to better formulate strategies for combatting the negative effects of myeloid cell activation after injury.