Oral immune regulation using colitis extracted proteins for treatment of Crohn's disease: Results of a phase I clinical trial

Abstract

Aim: To evaluate safety and possible efficacy of induction of oral immune regulation using colitis extracted proteins (CEP) in Crohn's disease (CD) subjects. Methods: Ten CDs were treated orally with autologous CEP thrice weekly for 16 wk. Subjects were monitored for CDAI and IBDQ. Immune modulatory effect was assessed by T-lymphocyte FACS analysis, CEP-specific IFNγ ELISPOT assay and cytokine levels. Results: Induction of oral immune regulation significantly ameliorated disease activity. All (10/10) subjects had clinical response (CDAI ≤ 70) and 7/10 achieved clinical remission (CDAI ≤ 150). Significant increase in mean IBDQ score was noted (134±9 vs 164±12). No treatment-related adverse events were noted. High levels of CEP-specific IFNγ spot forming colonies were detected in five subjects prior to treatment and in all five, a marked decrease was observed. The CD4+/CD8+ lymphocyte ratio and peripheral NKT cell numbers increased significantly, in 7/10 and in 5/10 subjects, respectively. Significant increase in serum IL-10 and IL-4 levels was observed in 7/10 subjects during treatment period. Conclusion: Immune regulation via oral administration of CEP is a safe and possibly effective treatment for subjects with moderate CD and may provide means of antigen-specific immune modulation. © 2005 The WJG Press and Elsevier Inc. All rights reserved.