For example, in vitro experiments using peripheral blood mononuclear cell (PBMC) cultures from IBS patients showed a reduced secretion of IL-10 [69,70], an anti-inflammatory cytokine, and an elevated level of proinflammatory cytokines like IL-1β, IL-6, IL-8, IL-12, and TNF at steady state conditions [69,70,71]. This evidence concerns the gene TNF and irritable bowel syndrome.