While the rival of anti-TNF has revolutionized management of patients with IBD, the development of new therapeutic strategies is necessary for several reasons: nearly one-third of patients show no response to these molecules, the secondary effects are frequent and the high cost is often a deterrent in emerging countries precisely where the number of patients continues to increase.

Cell therapy comprises different strategies for delivering new cells with therapeutic properties into our body. This providing of new cells can be done by bone marrow graft or by isolated cells. In inflammatory bowel diseases, several therapeutic trials have already shown the efficacy of autologous administration of stromal mesenchymal cells during Crohn's disease. Indeed, this strategy is being financed by the DigestScience Foundation.

Several weeks ago, a clinical phase 1/2a trial was published in Gastroenterology on the use of a subpopulation of regulator T lymphocytes (Tregs) activated by ovalbumin: Ova-Treg. Testing of the Ova-Treg concept had been previously carried out on animal colitis models and showed the intestinal anti-inflammatory effect of these cells, which locally produced large quantities of IL-10. The study included 20 patients with a severe form of CD not responding to conventional treatment. They were separated into 4 groups, each of which received different doses of Ova-Treg. The cells used, which came from the blood of each patient, were cultured in the presence of ovalbumin and cloned before being re-injected iv. On the whole, the response to treatment, as defined by a reduction of 100 points in the patient activity score, was 40%. Maximal efficacy was obtained in patients who had received a million cells, enabling a response in 75% of patients and significant improvement in their quality of life.

This novel approach is highly encouraging and a new international multicentric study is scheduled in the next few months.

Références
Gastroenterology 2012;143:1207-1217
"Safety and Efficacy of Antigen-Specific Regulatory T-Cell Therapy for Patients With Refractory Crohn's Disease"