Tracking stem cells in the incisional hernial sac: a gaze beyond pure tissue repairs

ABSTRACT Objective: the hernial sac is typically a bilayer structure consisting of connective tissue lined underneath by peritoneum. Some incidental findings on it, like smooth muscle cells and heterotopic ossification, can be explained as the end-stage metaplasia from undifferentiated cells. This study aimed to search for mesenchymal stem cells in the incisional hernial sac by an immuno-histochemistry screening test. Methods: fifteen specimens of them were submitted to histochemistry analysis using CD133 monoclonal antibodies, a specific marker of mesenchymal stem cells. The biopsies were obtained from patients submitted to pure tissue repair for incisional hernias - the transposition with the hernial sac technique (Lázaro da Silva, 1971). Results: two-thirds of the specimens expressed on average 20 (twenty) CD133+ cells in each one. Conclusion: despite the screening nature of this study, the hernial sac may be considered a source of stem cells. This could explain those abnormal findings, and perhaps the induction of new fibroblasts in procedures that use it to optimize wound healing.