CCR9 and colitis: Herein with a myeloid HIF-2α knockout, we saw an induction of (i) other proinflammatory cytokines than Il6 such as Il23, Il17, and Ifng and (ii) a higher recruitment of proinflammatory cells like neutrophils caused by increased Cxcl1 and T-cells driven by a gradient of Ccr9. This is likely to promote colitis progression.