Sex-distinct microglial activation and myeloid cell infiltration in the spinal cord after painful peripheral injury

•Spinal cord microglial activation, characterized by increases in Iba1 and TMEM119 expression, occurs in both male and female mice, with a delayed time course of activation in females.•TMEM119, a microglial-specific marker, is not stably expressed in the spinal cord in the context of peripheral injury, and in fact increases to a similar degree as Iba1 after injury.•Limited numbers of Iba1+TMEM119− cells were identified in the spinal cord after peripheral injury and these infiltrating myeloid lineage cells represented two unique cell populations: Ly6G + neutrophils and Ly6G- macrophages/monocytes.•Spinal cord resident TMEM119+ microglia are the primary cellular source of CNS cytokines, IL6 and IL1β, released after peripheral injury.