S100A8 and inflammatory bowel disease: Within the IBD cohort, the acquired serum level data of 52 analytes did not result in specific grouping of patients when subjected to unsupervised clustering analyses (Fig. 1B), but yielded 9 markers with concentrations that differed in patients with future unstable remission compared to those with future stable remission (i.e. without subsequent relapse): already at the baseline visit (T1) serum levels of IL-1β, IL-15, IL-18, IL-21, IL-25, IFN-β, CXCL9, CXCL10 and S100A8/A9 were higher in those who later experienced disease relapse (Fig. 1C, Table 2).