This indicates that the oxygen-rich environment meets the need of high metabolism of a keloid, inhibits the secretion and release of inflammatory factors, and attenuates the level of the inflammatory response.[38,39] HBO therapy significantly decreased the expression levels of IL-12p40, MIP-1β, and PDGF-BB, and it increased the expression level of IL-1Ra; thus, suggesting that HBO therapy has protective effects against the inflammatory responses during the progression of a keloid. The gene discussed is CCL4; the disease is keloid.