Leukoapheresis in Crohn's disease: the final curtain?

• Crohn's Colitis

In 2012, our therapeutic armamentarium is still limited in patients with Crohn's disease (CD) refractory to standard medications. Anti-tumor necrosis factor (TNF) agents (eg, infliximab and adalimumab) have changed the way these patients are treated. However, only one third of patients with CD who are administered infliximab or adalimumab will be in clinical remission at 1 year.1 In addition, secondary loss of response is relatively frequent with all anti-TNF agents.2 New therapeutic options are therefore eagerly awaited for these patients. With this in mind, the relative newcomer apheresis looked promising.

Cytapheresis or depletion of activated granulocytes and monocytes/macrophages from the circulation could theoretically reduce leukocyte-dependent inflammation in immune-mediated disorders such as the inflammatory bowel diseases (IBD). One mechanism through which this can be achieved is using the medical device Adacolumn, an extracorporeal circulatory system with a G-1 column (Otsuka Pharmaceutical Europe Ltd., Middlesex, UK) that mediates selective cytapheresis of activated granulocytes and monocytes/macrophages from venous blood. The column contains cellulose acetate beads (2 mm in diameter) that act as carriers to selectively adsorb granulocytes and monocytes/macrophages, but only a much more limited number of lymphocytes.

The column is initially bathed in sterile saline, but once blood is added and comes into contact with the cellulose acetate beads, adhesion and absorption of peripheral blood cells begins. Immune complexes (IC) and …