Presentation Authors: Nikolai Sopko*, Gregory Joice, Uros Milenkovic, Xiaopu Liu, Baltimore, MD, Michael Bickell, Rafael Carrion, Tampa, FL, Ani Singh, Trinity Bivalacqua, Baltimore, MD
Introduction: Biologically sourced materials are commonly are used for reconstructive urology including decellularized human epicardium (DHE) and decellularized porcine small intestinal submucosa (SIS). Although effective, they are expensive and have theoretical risks of infection and inconsistency given their allogenic andxenogenic sources. We have engineered a novel molded collagen I-based scaffold that can be customized and used as a reconstructive material in complex urological repairs. We sought to compare the mechanical and biological properties of our molded collagen scaffolds with conventional biological-sourced materials
Methods: Stress and strain were measured for DHE, SIS, porous molded collagen (PMC) and cross-linked molded collagen (CMC). Scanning electron microscopy (SEM) was used to assess cross-sectional and surface architecture. All four materials were implanted subcutaneously in rats and harvested 3d, 7d, 14d, and 28d and evaluated for persistence, gross appearance in situ, angiogenesis, and cellular infiltration assessed by immunohistochemistry (IHC), immunofluorescence (IF), and quantitative polymerase chain reaction (qPCR).
Results: PMC and CMC had stress and strain properties similar to SIS and DHE, respectively. SEM demonstrated the large porous nature of PMC and the dense collagen sheets of CMC (Figure 1). All materials persisted to 28 days. None of the materials appeared grossly infected or inflamed. All materials had evidence of macrophage infiltration identified by CD68 staining by 28d. qPCR demonstrated expression of genes associated with neovascularization and inflammation in all materials that increased with time consistent with rat endothelial cell antigen (RECA) labeling of neovascularization on IF.
Conclusions: Engineered molded collagen scaffold may provide an inexpensive, consistent, and safe source of materials that can be customized and used for complex reconstructive urological applications.