Pharmacological Mobilization and Recruitment of Stem Cells in Rats Stops Abdominal Adhesions After Laparotomy.

Adhesions are a very common complication in the abdominal surgery. Animal studies and human trials have evaluated strategies designed to reduce and prevent postsurgical adhesions but few have an evidence base that justifies routine use. A strategy to prevent adhesions effectively remains an urgent need. We studied a reproducible model of intra-peritoneal adhesion formation in rats using laparotomy with several peritoneal sutures to produce the adhesions. Here we show that entraining endogenous stem cells into injury sites using the combined effect of AMD3100 and low-dose FK-506 (AF) can reduce the adhesion score significantly and abolish peritoneal adhesions in 45% of animals in a rat model of severe postsurgical intra-abdominal adhesions, compared with saline controls. Searching for mechanisms, we found AF treatment dramatically increased SDF-1 expressing cells, HGF expressing Ym1+ M2 macrophages and CD133+ stem cells in the injury sites of peritoneal surface at day 5 post-operation. Our results demonstrate that medically induced recruitment of autologous stem cells using AF significantly reduced postsurgical intra-abdominal adhesions. These findings suggest a novel effective therapeutic approach to preventing adhesions in patients.