IL6 and irritable bowel syndrome: Although low concentrations of TNFα were detected in IBS patients and HV with the Luminex assay, no differences were seen when comparing IBS and HV or between IBS patient subgroups; IL-6 and IL-10 were largely undetectable, and no differences were observed between groups (data not shown), suggesting that serum cytokines are less sensitive to detect immune activation in IBS.