In addition to the T-helper cell type (Th) 1 and Th2 immune responses, other subsets of T cells, namely, Th17 and regulatory T (Treg) cells, likely play a role in IBD, because the IL13/TH17 pathway has been postulated as an important biomarker of active IBD [17, 116], and the presence of IBD, but not the genetic load, alters mRNA expression of IBD-associated Th17/IL-13 genes [115]. This evidence concerns the gene IL13 and inflammatory bowel disease.