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The development of standardized cross-species evaluation frameworks is urgently needed for absorbable extracellular matrix (ECM) meshes, due to significant variations in safety and efficacy across tissue sources. This study establishes a multi-dimensional assessment system to quantify material-specific bio-functional correlations. Three ECM meshes-human acellular dermis (HAD), porcine acellular dermis (PAD), and porcine small intestinal submucosa (SIS)-were systematically characterized using integrated in vitro and in vivo analyses. Assessments included physicochemical properties (e.g., degradation kinetics via collagenase digestion), immunogenic residues (α-Gal epitopes and DNA quantification), and biocompatibility. In vivo performance was evaluated using rabbit subcutaneous (for degradation and immune response) and rat abdominal defect models (for macrophage polarization: CD206⁺/CD86⁺ ratio and collagen deposition). HAD exhibited superior structural stability (82.3% ± 1.2% residual mass after 7-day collagenase digestion), whereas SIS degraded most rapidly (10.5% ± 0.42%; p < 0.01 vs PAD) but provoked severe foreign body reactions (2.3-fold higher vs HAD at 13 weeks, p = 0.017). Notably, HAD uniquely promoted sustained M2-dominant macrophage polarization (CD206⁺/CD86⁺ ratio = 2.1 vs SIS = 0.7), which reduced inflammation and enhanced collagen remodeling (p < 0.05 vs SIS). Serum metabolomic analysis indicated that ECM mesh implantation induced a reprogramming of host amino acid metabolism, marked by a notable acceleration in L-methionine metabolism. The proposed integrated evaluation framework successfully identifies material-specific correlations among degradation behavior, immune response, and metabolic regulation, providing critical benchmarks for the rational design of immunomodulatory ECM meshes.
Transcatheter aortic valve replacement (TAVR) has emerged as an effective therapy for inoperable patients with severe aortic stenosis (AS). However, calcification-induced limited durability restricts its application. Fish swim bladders (FSB), which are resistant to calcific degeneration, offer a viable solution to this challenge. In this study, we developed a new TAVR device using FSB as the valve leaflet. Furthermore, the in vitro durability, in vivo performance, and size selection of this TAVR device were assessed by an experimental study and finite element analysis. A self-expandable TAVR device was fabricated by suturing the FSB films into a 23 mm nitinol alloy frame. Further, hemodynamic performance, such as effective orifice area, transvalvular pressure difference and regurgitant fraction, the durability was tested by the pulsatile flow test and accelerated fatigue test, according to the ISO 5840-3. The effect of release size on hydrodynamic performance was also investigated. Finally, the in vivo performance of the TAVR device were examined using a porcine implantation model. The results showed that the strength of the FSB films satisfied the requirements for valve leaflets. The hemodynamic performance of the FSB TAVR device met the requirements of ISO 5840-3 standards. After 400 million cycles, the FSB showed no fiber loss, torn, perforation, or other valve failure phenomena. In porcine models, the devices were well-positioned, functioned well with no stenosis immediately after the operation. Collectively, we successfully developed a TAVR device with FSB as valve leaflets that exhibited good fatigue resistance. STATEMENT OF SIGNIFICANCE: The source of material for the leaflets of commercialized biological heart valves (BHVs) is mainly bovine pericardium, but this material suffers the following problems: large and uneven thickness of the material, the presence of α-Gal and Neu5Gc antigens, and the susceptibility to structural valve degradation (SVD). New material for BHVs leaflets is rarely reported. In this study, we prepared a transcatheter aortic valve (TAV) and performed long-term in vitro and short-term in vivo studies using fish swim bladder (FSB) as the leaflets. The study confirmed that FSB TAV device can complete 400 million fatigue tests and maintain the good morphology of the leaflets, and that it still maintains good functionality after a certain amount of compression, indicating that FSB is a promising material for leaflets.