C-176 does not alter microglial phenotype
Since we identified an alteration to STING mRNA expression and TBK1 and p-TBK1 expression in vehicle treated mice 24h post-TBI, we wanted to elucidate if these changes also resulted in altered microglial activity. Immunohistochemical analysis was conducted on CX3CR1eGFP mice which have fluorescently tagged microglia. Morphological analysis was conducted on CX3CR1eGFP mice 24h-post TBI to quantify any phenotypical changes to the microglia that could indicate alterations to the inflammatory environment in the CNS. STING was found to strongly colocalise with CX3CR1-tagged microglia 2h-post TBI (Fig 5). There was a small increase in soma size detected post-TBI compared to the microglia contralateral to the TBI-lesion, however, no differences in total branch length, cell area or soma area were observed between vehicle-treated and C-176 treated mice post-TBI (Fig 6).