Optimization and Critical Evaluation of Decellularization Strategies to Develop Renal Extracellular Matrix Scaffolds as Biological Templates for Organ Engineering and Transplantation

The ability to generate patient‐specific cells through induced pluripotent stem cell (iPSC) technology has encouraged development of three‐dimensional extracellular matrix (ECM) scaffolds as bioactive substrates for cell differentiation with the long‐range goal of bioengineering organs for transplantation. Perfusion decellularization uses the vasculature to remove resident cells, leaving an intact ECM template wherein new cells grow; however, a rigorous evaluative framework assessing ECM structural and biochemical quality is lacking. To address this, we developed histologic scoring systems to quantify fundamental characteristics of decellularized rodent kidneys: ECM structure (tubules, vessels, glomeruli) and cell removal. We also assessed growth factor retention—indicating matrix biofunctionality. These scoring systems evaluated three strategies developed to decellularize kidneys (1% Triton X‐100, 1% Triton X‐100/0.1% sodium dodecyl sulfate (SDS) and 0.02% Trypsin‐0.05% EGTA/1% Triton X‐100). Triton and Triton/SDS preserved renal microarchitecture and retained matrix‐bound basic fibroblast growth factor and vascular endothelial growth factor. Trypsin caused structural deterioration and growth factor loss. Triton/SDS‐decellularized scaffolds maintained 3 h of leak‐free blood flow in a rodent transplantation model and supported repopulation with human iPSC‐derived endothelial cells and tubular epithelial cells ex vivo . Taken together, we identify an optimal Triton/SDS‐based decellularization strategy that produces a biomatrix that may ultimately serve as a rodent model for kidney bioengineering.