Absence of CHOP reduced inflammation in D469del-COMP hind limbs. Panel 1 :A variety of mRNAs involved in survival, ROS, inflammation, cytokines, and eosinophilia are altered in the absence of CHOP. mRNA levels from control mice were set to 1. Fold change values below 1 indicate decrease in expression and values above 1 indicate an increase in expression. No change in expression = 1. D469/CHOP−/− = D469del-COMP/CHOP−/−; * = growth plate and articular cartilage. Panel 2: Tibias were collected from D469del-COMP and D469del-COMP/CHOP−/− P28 mice for immunostaining. The D469del-COMP tibias showed more intense YM1 immunostaining in the articular cartilage and growth plate (A, D) than D469del-COMP/CHOP−/− mice (B, C, E, and F). The tibias shown in B, C, E, and F display the range of YM1 staining in the D469del-COMP/CHOP−/− mice. Bar = 100 μm.