Anti-inflammatory protein TNFα-stimulated gene-6 (TSG-6) reduces inflammatory response after brain injury in mice

Abstract Background: Current research suggests that the glial scar surrounding penetrating brain injuries is instrumental in preserving the surrounding uninjured tissue by limiting the inflammatory response to the injury site. We recently showed that tumor necrosis factor (TNF)-stimulated gene-6 (TSG-6), a well-established anti-inflammatory molecule, is present within the glial scar. In the present study we investigated the role of TSG-6 within the glial scar. Methods: TSG-6 null and littermate control mice were subjected to penetrating brain injuries (2 mm puncture wound to the frontal cortex), after which both the injury site and remaining injured hemisphere were analyzed. The presence of activated astrocytes, inflammatory markers and glial scar components was evaluated by real-time PCR and immunofluorescence. Results: Our findings show that mice lacking TSG-6 present a more severe inflammatory response after injury, which was correlated with an enlarged area of astrogliosis beyond the injury site. Conclusion: Our data provides evidence that TSG-6 has an anti-inflammatory role within the glial scar.