Resource-efficient decellularization of human iliac arteries using a 3D-printed radial-flow bioreactor: CFD-guided design and experimental validation

Vascular bypass and reconstruction often rely on synthetic or allogeneic grafts, which may exhibit limited long-term patency and adverse host responses. Decellularized extracellular matrix (ECM) scaffolds offer a promising alternative; however, conventional perfusion protocols are frequently reagent-intensive and technically demanding. This study introduces a 3D-printed radial-flow bioreactor designed for the decellularization of human iliac arteries with reduced detergent consumption. Arteries were perfused radially for 8 days using a 1% w·v⁻¹ sodium dodecyl sulfate solution, followed by deoxyribonuclease I treatment and phosphate-buffered saline washes. Decellularization efficacy was quantified by nuclear density using 4',6-diamidino-2-phenylindole staining, and residual DNA was measured by fluorometric quantification. The radial-flow bioreactor achieved approximately 97% nuclear reduction using 70 mL of detergent solution, compared to 250 mL required by a benchmark perfusion setup. Residual DNA content was reduced to 40 ± 5.2 ng·mg⁻¹, while collagen and elastin retention remained high. Computational fluid dynamics (CFD) revealed a uniform wall shear stress distribution along the luminal surface (mean wall shear stress ≈ 0.97 Pa) and a minimal pressure drop (ΔP ≈ 116 Pa) under simulated conditions. These findings provide a mechanistic rationale for the observed performance and support further device optimization. Overall, the proposed radial-flow bioreactor provides a resource-efficient and experimentally validated approach for human iliac artery decellularization.