Traumatic brain injury (TBI) provokes inflammatory responses, including a dramatic rise in brain macrophages in the area of injury. The pathway(s) responsible for macrophage infiltration of the traumatically injured brain and the effects of macrophages on functional outcomes are not well understood. C-C-chemokine receptor 2 (CCR2) is known for directing monocytes to inflamed tissues. To assess the role of macrophages and CCR2 in TBI, we determined outcomes in CCR2-deficient (Ccr2 -/ -) mice in a controlled cortical impact model. We quantified brain myeloid cell numbers post-TBI by flow cytometry and found that Ccr2 -/ -mice had greatly reduced macrophage numbers (*80-90% reduction) early post-TBI, compared with wild-type mice. Motor, locomotor, and cognitive outcomes were assessed. Lack of Ccr2 improved locomotor activity with less hyperactivity in open field testing, but did not affect anxiety levels or motor coordination on the rotarod three weeks after TBI. Importantly, Ccr2-/ -mice demonstrated greater spatial learning and memory, compared with wildtype mice eight weeks after TBI. Although there was no difference in the volume of tissue loss, Ccr2 -/ -mice had significantly increased neuronal density in the CA1-CA3 regions of the hippocampus after TBI, compared with wild-type mice. These data demonstrate that Ccr2 directs the majority of macrophage homing to the brain early after TBI and indicates that Ccr2 may facilitate harmful responses. Lack of Ccr2 improves functional recovery and neuronal survival. These results suggest that therapeutic blockade of CCR2-dependent responses may improve outcomes following TBI.

As one of few studies to track the complete course of sequential HCC therapies, the findings of the present study suggest that HCC patients with intermediate-stage (BCLC stage B) disease may benefit from aggressive interventions not currently included in societal guidelines.

State policies play a significant role in determining access to HIV drugs, and state policies can be used to reduce racial/ethnic disparities in pharmaceutical access. Overall, eliminating racial/ethnic disparities in access to HIV pharmaceuticals appears to be an achievable goal.