DataSheet3_Small intestinal submucosa-derived extracellular matrix as a heterotopic scaffold for cardiovascular applications.docx

Structural cardiac lesions are often surgically repaired using prosthetic patches, which can be biological or synthetic. In the current clinical scenario, biological patches derived from the decellularization of a xenogeneic scaffold are gaining more interest as they maintain the natural architecture of the extracellular matrix (ECM) after the removal of the native cells and remnants. Once implanted in the host, these patches can induce tissue regeneration and repair, encouraging angiogenesis, migration, proliferation, and host cell differentiation. Lastly, decellularized xenogeneic patches undergo cell repopulation, thus reducing host immuno-mediated response against the graft and preventing device failure. Porcine small intestinal submucosa (pSIS) showed such properties in alternative clinical scenarios. Specifically, the US FDA approved its use in humans for urogenital procedures such as hernia repair, cystoplasties, ureteral reconstructions, stress incontinence, Peyronie’s disease, penile chordee, and even urethral reconstruction for hypospadias and strictures. In addition, it has also been successfully used for skeletal muscle tissue reconstruction in young patients. However, for cardiovascular applications, the results are controversial. In this study, we aimed to validate our decellularization protocol for SIS, which is based on the use of Tergitol 15 S 9, by comparing it to our previous and efficient method (Triton X 100), which is not more available in the market. For both treatments, we evaluated the preservation of the ECM ultrastructure, biomechanical features, biocompatibility, and final bioinductive capabilities. The overall analysis shows that the SIS tissue is macroscopically distinguishable into two regions, one smooth and one wrinkle, equivalent to the ultrastructure and biochemical and proteomic profile. Furthermore, Tergitol 15 S 9 treatment does not modify tissue biomechanics, resulting in comparable to the native one and confirming the superior preservation of the collagen fibers. In summary, the present study showed that the SIS decellularized with Tergitol 15 S 9 guarantees higher performances, compared to the Triton X 100 method, in all the explored fields and for both SIS regions: smooth and wrinkle.

结构性心脏病变通常通过人工补片进行手术修复，此类补片可分为生物源性与合成源性两类。当前临床场景中，源自异种支架脱细胞处理的生物补片愈发受到关注，因为这类补片在移除天然细胞及残留物质后，仍可保留细胞外基质（extracellular matrix, ECM）的天然结构。将其植入宿主体内后，此类补片可诱导组织再生与修复，促进血管生成、细胞迁移、增殖以及宿主细胞分化。最终，脱细胞异种补片会发生细胞再定植，从而降低宿主针对移植物的免疫介导应答，并预防装置失效。

猪小肠黏膜下层（porcine small intestinal submucosa, pSIS）在其他临床场景中已展现出此类特性。具体而言，美国食品药品监督管理局（US FDA）已批准其用于人类泌尿生殖系统手术，包括疝修补术、膀胱成形术、输尿管重建术、压力性尿失禁、佩罗尼氏病（Peyronie’s disease）、阴茎弯曲畸形，甚至针对尿道下裂及尿道狭窄的尿道重建术。此外，它还成功应用于年轻患者的骨骼肌组织重建。不过，在心血管应用领域，相关研究结果尚存争议。

本研究旨在验证我们基于Tergitol 15 S 9开发的SIS脱细胞方案，并将其与我们此前已验证但现已无法在市场上购得的高效方案（Triton X 100）进行对比。针对两种处理方案，我们分别评估了细胞外基质超微结构、生物力学特性、生物相容性以及最终的生物诱导能力。整体分析显示，SIS组织宏观上可分为两个区域：光滑区域与褶皱区域，其超微结构、生化及蛋白质组学特征均与此对应。此外，Tergitol 15 S 9处理不会改变组织的生物力学性能，其效果与天然组织相当，且证实可更好地保留胶原纤维。

综上，本研究表明，相较于Triton X 100方法，采用Tergitol 15 S 9脱细胞处理的SIS在所有考察维度以及两个SIS区域（光滑区域与褶皱区域）中均表现出更优异的性能。