CS and inflammatory bowel disease: Here, we report that patients with active IBD exhibit increased expression of “pro-inflammatory” isomers (CS-C (6S) and CS-E (4S6S)) and corresponding decrease in “matrix stabilizing” isomers, (CS-A (4S) and DS (2S4S)), in the colon (Fig. 3, Table 2), a pattern that also occurs in tandem with an apparent overall reduction in CS/DS-GAG abundance (Fig. S5).