The present invention provides a method of determining whether a patient with inflammatory bowel disease (IBD) and who has been treated with anti TNFα therapy is in immunological remission (IR), said method comprising determining the level of a cytokine selected from TNFα, IL-17 and IFN-y in a Gl mucosal sample from said patient. Also provided are methods of prognosis and treatment using said method of determination, in particular discontinuing treatment if said patient is in IR and continuing treatment if said patient is not in IR.