The dynamics of the rectal surface epithelial lymphocyte and leucocyte response to wheat, gluten, and gliadin enema challenges in control individuals and in patients with coeliac sprue in remission is shown. There is a clear increase in intraepithelial lymphocytes and polymorphonuclear (PMN) leucocytes in response to these enemas in coeliac sprue, but not in controls. The peak response was at eight hours and cleared within 24 hours. There was no change in the crypt epithelium. These data add further support to the role of wheat, gluten, and gliadin in the pathogenesis of coeliac sprue, at least in the rectal mucosa.