Is This the Era of Interstitial Cells of Cajal Transplantation?

Article: Bone marrow derived Kit-positive cells colonize the gut but fail to restore pacemaker function in intestines lacking interstitial cells of Cajal CC This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons. org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Although not life-threatening, gastrointestinal (GI) motility disorders, such as achalasia, gastroparesis, intestinal pseudo-obstruction or slow transit constipation, can seriously affect a pa-tient's quality of life. 1-5 Furthermore, since the pathophysiology of such disorders is often incompletely understood, development of a curative treatment is very difficult. Many studies have reported that loss of interstitial cells of Cajal (ICC), or injury to ICC networks can play an improtant role in various chronic GI motility disorders, including the aforementioned conditions. 6-10 ICC are known to control spontaneous contraction in GI smooth muscle through the generation of slow waves. 11-13 ICC also mediate inhibitory neurotransmission in such areas as the lower esoph-ageal sphincter and the pylorus. 14 Therefore, loss of ICC or injury to ICC networks is strongly associated with the development of GI motility disorders. In this respect, recovery of lost ICC or disrupted networks may represent a revolutionary therapeutic modality for various GI motility disorders. While it is known that ICC arise from mesenchymal precursors , 15 the regulation of their populations and life cycles has not been fully characterized. Although several animal studies have demonstrated the plasticity and regenerative capacity of ICC in neonatal and adult ICC-disruption models, 7,16,17 the exact underlying mechanisms are unclear. Among the several theories regarding ICC homeostasis, the role of stem cell is particularly prevalent. 18 In adults, pluripotent stem cells are derived from several organs, including the bone marrow (BM), adipose tissue and blood. 19 Recent studies have shown that BM-derived mesen-chymal stem cells are not only capable of differentiating into os-teoblasts, adipocytes, chondrocytes and myocytes, but also able to repopulate injured liver, lung or heart tissue following BM transplantation. 20 In the wake of these observations, the intriguing possibility that BM-derived stem cells could differentiate into ICC has been raised. In this context, 2 recent studies have already generated positive results, 21,22 with 1 study even establishing evidence of improved motility. 22 In that study, however, detailed functional stud