In such a milieu, there may exist mechanisms to restrict local activated, antigen experienced CD8+ T cells from developing a senescent phenotype; as many senescent functional features, including high cytotoxic potential [8, 64] and proinflammatory cytokine secretion [65, 66], could contribute to gut mucosal inflammatory disorders such as Coeliac Disease and Crohn’s Disease. This evidence concerns the gene CD8A and Crohn disease.