LB-S&T-17 THE IMPACT OF MANGANESE SUPEROXIDE DISMUTASE GENE IN SMOOTH MUSCLE ON THE URETHRAL FUNCTION OF STRESS URINARY INCONTINENCE MICE MODEL

INTRODUCTION AND OBJECTIVES: Although various novel tissue engineered urethral scaffolds have been reported in the last decade, less reports are focused on the multi-scale structure of scaffold. Therefore, the structure of those scaffolds are quite different from the actual urethral tissue. In this study, we investigate the feasibility of constructing the 3D multi-scale modified bulbar urethral scaffold, which can be similar to the native urethral structure. METHODS: Five volunteers’ images about their bulbar urethra were obtained through the ultrasound. Those data were used to reform the 3D digital model of bulbar urethra. By using the indirect 3D printing technique, the mould of individual bulbar urethra was constructed. The silk fibroin solution was cast into this mould and freeze-dry procedure was performed, subsequently. After forming the macro porous scaffold, the Acetobacter xylinum was incubated into the scaffold to assemble the cellulose layer. The mechanical tests were perform in all scaffolds. The details of final scaffold were evaluated by the micro CT and scanning electron microscope. Meanwhile, the details of native bulbar urethral structure was compared with those in the constructed scaffold. RESULTS: All scaffold exhibited the ideal mechanical properties. The gross view of the constructed scaffolds was similar to the actual bulbar urethra. In the micro-scale, a typical bilayer structure could be noticed in the scaffold. The pore size of scaffold inner surface was 12.3 2.4mm, which is close to the native urethra (15.2 3.6mm). The pore size of scaffold sublayer and native urethra were 140 34mm and 146 30mm, respectively. In the nano-scale, no statistical difference of fiber diameter was found in the constructed scaffold and native urethra (22.3 6.3 nm vs 24.6 5.0 nm). CONCLUSIONS: Our study demonstrated the feasibility of constructing individual 3D urethral scaffold, which was similar to the structure of native bulbar urethra in multi-scale. Furthermore, the structure of this scaffold could be easily modified by controlling the production process according to the demanding of design. It provide a novel conception for constructing the tissue engineering urethral scaffold.