GSE196121
Transcriptome analysis using RNA sequencing of the perilesional cortex in traumatic brain injury mice treated with CSF1R inhibitor or vehicle
C57BL6 mice were subjected to a controlled cortical impact (CCI) to induce a unilateral traumatic brain injury (TBI). After surgery, mice were treated for 5 days with the CSF1R antagonist, PLX3397 or vehicle by daily i.p. injections. PLX3397 is an inhibitor of Colony Stimulating Factor receptor 1 (CSF1R) that leads to a depletion of microglial cells which was confirmed by immunohistochemistry in a subgroup of mice at day 5. Termination of PLX3397 allows for a repopulation of microglial cells which was near complete at 30 days, as assessed by immunofluorescence studies. Perilesional cortical tissue was obtained at the late time point of 30 days after TBI to assess lasting effects of microglia depletion for cortical reorganization that manifested at the transcriptional level. The RNAseq study was done in male and female mice (PLX3397 n = 5 male, 5 female; vehicle n = 5 male, 5 female). Behavioral scores for well-being and motor functions were obatined repeatedly during the observation time. Histology of brain lesion size, indices of neuronal damage and neuroinflammation were obtained at 5d and 30d after TBI. Microglia depletion (PLX3397 treatment) did not reduce the lesion volume and hindered phagocytosis and removal of the hematoma at 5 days, but reduced structural brain damage and neuron loss at 30 days after the injury. Neuroinflammatory markers tended to be lower in PLX3397 treated male than female mice which was associated with better neurological outcome. Overall, CSF1R inhibition provided only subtle lasting beneficial effects. Overall design: RNA was extracted from perilesional cortex 30d after TBI in mice treated with PLX3397 (n = 10) or vehicle (n = 10) from d1-d5. RNA and was analyzed by RNA sequencing in 10 biological replicates per treatment group using an Illumina NovaSeq 6000 system.