Intriguingly in animals exposed only to mTBI, a significant increase (×3 fold) in the Th17 cytokine IL-17A was observed compared to controls, and this effect was abrogated in the combination groups, possibly indicating separate systemic inflammatory response(s) to PTSD and head injury, with mTBI involving a Th17 classical T lymphocyte inflammatory response at this acute time point in our model. Here, IL17A is linked to post-traumatic stress disorder.