G. P. Liao1, R. A. Hetz1, C. J. Corkins1, T. G. Hughes1, H. Xue1, Y. Li1, K. P. Lally1, C. S. Cox1 1University Of Texas Health Science Center At Houston,Pediatric Surgery,Houston, TX, USA
Introduction:
Tissue engineering for congenital diaphragmatic hernia (CDH) repair seeks to improve biomechanical compatibility while reducing device failure. Decellularized scaffolds have the potential of regenerating the structure and function of their native tissue over commercially available matrices from other tissues, but lack immediate strength. Our lab explored using patches constructed with decellularized rat diaphragm combined with porcine bladder matrix in a preclinical rodent model for potential translational repair of CDH diagnosed in utero.
Methods:
A composite patch made of decellularized rat diaphragm combined with porcine bladder matrix was implanted in rats with surgically created left sided diaphragmatic hernias (n=5). Control rats received either decellularized diaphragm patch alone (n=9) or porcine bladder matrix patch alone (n=5). At four months post implantation, the rats were weighed and their diaphragms explanted and subjected to physiologic testing of maximum force generation and modular tensile strength.
Results:
Rats repaired with the composite patch gained 124+/-6 grams, compared to 100+/-2 grams with the decellularized diaphragm alone (p=0.02) and 77 +/-4 grams with the porcine bladder matrix alone (p=0.003). Pulse stimulation of explanted hemidiaphragms repaired with the composite patch generated 71+/-18% of the contralateral hemidiaphragm force compared to 47+/-8% with the porcine bladder matrix patch alone (p=0.21) and 35+/-5% with the decellularized rat diaphragm patch alone (p=0.03). Composite patch hemidiaphragms had closer to normal (1 MPa) modular tensile strength, at 1.2+/-0.1 MPa than hemidiaphragms repaired with the decellularized rat diaphragm patch 1.8+/-0.2 MPa (p=0.01) and than porcine bladder matrix 1.8+/-0.3 (p=0.08).
Conclusion:
Diaphragmatic defects repaired with composite biological patches that combine decellularized native tissue and commercially available matrices improve diaphragmatic biomechanical function and modular tensile strength and are associated with improved weight gain.
