New bioresorbable wraps based on oxidized polyvinyl alcohol and leukocyte-fibrin-platelet membrane to support peripheral nerve neurorrhaphy: preclinical comparison versus NeuraWrap

Abstract

Nerve wrapping improves neurorrhaphy outcomes in case of peripheral nerve injuries (PNIs). The aim of this preclinical study was to assess the efficacy of two novel biodegradable wraps made of a synthetic 1% oxidized polyvinyl alcohol (OxPVA) and a natural leukocyte-fibrin-platelet membrane (LFPm) versus the commercial product NeuraWrap. After rats sciatic nerve transection and neurorrhaphy, the wraps were implanted and compared for functional outcome, by sciatic function index assessment; structural characteristics, by histological/immunohistochemical analysis; ultrastructural features, by transmission electron microscopy. Moreover, a morphometric study was also performed and collagen distribution was observed by Second Harmonic Generation microscopy. After 12 weeks from implantation, all wraps assured nerve function recovery; no scar tissue/neuromas were visible at dissection. LFPm wraps were completely resorbed, while residues of OxPVA and NeuraWrap were observed. In all groups, biocompatibility was confirmed by the absence of significant inflammatory infiltrate. According to histological/immunohistochemical analysis and morphometric findings, OxPVA and LFPm wraps were both effective in preserving nerve integrity. These results assess that bioengineered OxPVA and LFPm wraps successfully guarantee favorable lesion recovery after PNI/neurorrhaphy and, in future, may be considered an interesting alternative to the commercial NeuraWrap.

Halogen-Mediated Partial Oxidation of Polyvinyl Alcohol for Tissue Engineering Purposes

“…Decellularized, homogenized and lyophilized sheets from articular cartilage, Wharton's Jelly and small intestine were cross-linked to PVA, obtaining bio-hybrid supports that sustained cell adhesion and proliferation [25][26][27]. In parallel, we proposed for the first time a standardized method to perform chemical oxidation of PVA by KMnO 4 in acid environment, in order to obtain scaffolds with improved swelling kinetics and protein adsorption/release ability with respect to neat PVA, as well as with tunable biodegradation properties which increase along with the degree of oxidation [19,22,23].…”

Biomaterials for Regenerative Medicine in Italy: Brief State of the Art of the Principal Research Centers

“…In addition, oxidized PVA has been modified to produce a biodegradable wrap for peripheral nerve injuries. Tests on rat sciatic nerve transection and neurorrhaphy showed favorable lesion recovery after 12 weeks of treatment with the oxidized PVA-based nerve wrap [ 70 , 71 ].…”

Experimental Methods to Simulate and Evaluate Postsurgical Peripheral Nerve Scarring

“…Many other devices/techniques have been investigated as antiscarring agents, and the preclinical results of these devices are reported in Table 6 . A very recent study compared the efficacy of two novel biodegradable wraps made of synthetic 1% oxidized polyvinyl alcohol (OxPVA) and a leukocyte-fibrin-platelet membrane (LFPm) with the commercial product NeuraWrap, demonstrating their effectiveness in sustaining nerve regeneration, together with an absence of scar tissue/neuroma formation and significant inflammatory infiltrate [ 81 ].…”