Remodeling of Suspended Small Intestinal Submucosa Venous Valve: An Experimental Study in Sheep to Assess the Host Cells' Origin

Cell colonization in degradable 3D porous matrices

“…14 SIS is a dense connective tissue harvested from the small intestine. SIS promotes cell migration of numerous cell types and has been tested for regeneration of diverse tissues including large vascular grafts, 15 venous valves and leaflets, [16][17][18] skin, 19 tendons 20 and wound dressing. 21 For urinary tract reconstruction, SIS has been used for bladder augmentation, [22][23][24] for ureter 25 and urethra 22,26 replacement and to promote regeneration of transitional epithelium, smooth muscle and peripheral nerves with no evidence of immunological rejection.…”

Small intestinal submucosa sandwich Zilver stent‐grafts for TIPS: Experimental pilot study in swine

“…The very thin (about 1 mm) neointima seen in portions of the stent-graft that were not in contact with venous wall, probably formed only from endothelial cells recruited from blood circulation, in a way similar to that found in the experimental study with remodeling of the suspended SIS venous valve (26). In stent graft portions that were in contact with the portal vein, the increased thickness (1-2 mm) of neointima was probably due to additional migration of cells from the adjacent venous wall (26).…”

“…SIS has been used in numerous tissue-engineering applications. The efficacy and safety of the SIS when used for the repair and reconstruction of various body tissues including cardiovascular, musculoskeletal, and urogenital structures has been shown in both animal studies and in human clinical studies (15,16,19,(26)(27)(28).…”

“…The majority of its collagen is type I, but other collagen types are also present. It contains natural extracellular matrix molecules such as fibronectin, hyaluronic acid, heparin, chondroitin sulfates A & B, heparan sulfate and several types of growth factors including fibroblast growth factor, transforming growth factor beta (TGF-B) and vascular endothelial cell growth factor (VEGF) (15,16,19,26,27). The US FDA has cleared SIS as a biomaterial for soft tissue repair and skin wound dressing.…”

“…The purpose of the presented pilot study was to evaluate the suitability of the nitinol stent-graft covered with another biomaterial, small intestinal submucosa (SIS), for creating experimental TIPS. SIS is a collagen-rich biomaterial that has been used as a graft material in many locations and regardless of location; SIS has served as a scaffold for remodeling by the host tissue (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26).…”