Anti-inflammatory effects of TGF-β1. The expression of proinflammatory cytokines IL-1β, TNF-α and IL-6 in rat lumbar spinal cords was measured by real time quantitative PCR. Peripheral nerve injury created an inflammatory reaction within the spinal cord by increasing levels of IL-1β and IL-6 but not TNF-α at the ipsilateral side. TGF-β1 significantly inhibited inflammatory response by reducing the increase of IL-1β and IL-6 expression. Data are shown as means ± SEM. ###p < 0.001, ipsilateral side vs. contralateral side; * p < 0.05, **p < 0.01, TGF-β1 treated vs. saline treated in their respective region.