A porous hydrogel scaffold mimicking the extracellular matrix with swim bladder derived collagen for renal tissue regeneration

As a worldwide public health issue, chronic kidney disease still lacks of effective therapeutic approaches due to the challenges in conventional organ transplantation and dialysis. Renal tissue engineering offers an advantageous therapeutic or regenerative option over typical donor organ. However, despite the great progress of decellularized extracellular matrix based scaffold for the renal regeneration, several safety concerns and complex composition still remain to be addressed. Herein, the extracellular matrix-mimicking hydrogel scaffolds were developed through covalent and physical cross-linking between swim bladder-derived natural collagen (COL) and anti-fibrosis chondroitin sulfate (CS) derivatives. The biomimetic hydrogels showed proper mechanical property, excellent thermal stability and high biocompatibility both in vitro and in vivo, by altering the mass ratio of COL and CS. When implanted in partially nephrectomized rat model, the 1COL/2CS scaffold enable it recruit more native kidney cells, reduce the tubular damage, and even induce the regeneration of renal tubular-like tissue and restore renal metabolic function more effectively comparing with the pure 2COL and 2CS scaffold. These results suggest that the biomimetic scaffold is a promising functional platform for treating renal diseases.