Preferential activation of CD4⁺Vβ5.2/5.3⁺ intestinal intraepithelial lymphocytes in the inflamed lesions of Crohn's disease

To analyze the nature of intestinal intraepithelial lymphocytes (iIELs) in inflammatory intestinal disease, we established T cell lines of iIELs isolated from endoscopic biopsied ileal and colonic mucosa of Crohn's disease patients. Seven T cell lines from the inflamed terminal ileum of 13 patients, but none of 16 T cell lines from normal terminal ileum, have shown a deviation of T cell receptor variable region gene usage and were enriched in the proportion of CD4⁺Vβ5.2/5.3⁺ cells. CD4⁺Vβ5.2/5.3⁺ cells in the T cell lines were not increased after stimulation with purified protein derivatives or 65-kDa heat-shock protein but significantly increased after stimulation with staphylococcal enterotoxins C1 and D. Those cells showed increased cytolytic activity against target cells cross-linked by anti-Vβ5.2/5.3 and produced a large amount of interferon-γ These results indicated that CD4⁺Vβ5.2/5.3⁺ iIELs were preferentially activated in the inflamed lesions of Crohn's disease and may play a possible role in the triggering and progression of human inflammatory intestinal disease.