Introduction and aim of the study: Electrospun hybrid meshes as the one investigated polycaprolactone (PCL) modified with ureidopyrimidinone (UPy) provide mechanical properties that may be better than standard synthetic materials. We aimed to investigate the medium term biocompatibility and biomechanical effects of rabbit abdominal wall reconstruction using UPy-PCL mesh.
Materials and methods: Twelve New-Zealand rabbits were implanted with electrospun (UPy-PCL; n = 12) or textile light weight polypropylene (PP; n = 12) Two full-thickness abdominal wall defects (30 × 5) were created, primarily repaired and reinforced with the mesh (40 × 25 mm). Rabbits were clinically evaluated and harvested at 30 and 90 days (n = 6 implants/group). Gross anatomy was noted (mesh size, adhesions, local complications). Explants were divided for uniaxial biomechanical testing and histology. Slides were semi-quantitatively investigated for fibrosis (Masson's Trichrome), foreign body giant cells (FBGC; H&E), myofibroblasts and vessels (α-SMA).
Results: We did not observe any clinical complications. Both implants were well incorporated, without herniation or infection, although with signs of UPy-PCL degradation (30d: 66%, 90d: 83%). There was an increase in mesh size (PP: 19%, UPy-PCL: 30%) and no adhesions. UPy-PCL had a stiffness closer to native muscle yet lower disruption force. There was more collagen deposition around PP and myofibroblasts and equal amount of vessels at 30days. UPy-PCL induced a vigorous FBGC reaction at 30 days decreasing by 90 days.
Interpretation of results: UPy-PCL electrospun mesh had a stiffness closer to native tissue, however lower disruption force compared to PP. It degrades from 30 days in rabbits.
Conclusions: UPy-PCL electrospun mesh seems biocompatible and has biomechanical properties closer to native tissue than PP. Its macroscopical degradation starts already at 30 days. This suggests that a longer degradation time may be useful.
© 2017 Published by Elsevier Inc.