White Rose University Consortium logo
University of Leeds logo University of Sheffield logo York University logo

Development of sterilisation strategies for decellularised peripheral nerve grafts

Holland, James Daniel Rhys (2019) Development of sterilisation strategies for decellularised peripheral nerve grafts. PhD thesis, University of Leeds.

[img]
Preview
Text
JH_THESIS_FINAL_2019.pdf - Final eThesis - complete (pdf)
Available under License Creative Commons Attribution-Noncommercial-Share Alike 2.0 UK: England & Wales.

Download (9Mb) | Preview

Abstract

Peripheral nerve injuries represent one of the leading causes of disability globally; due to limitations of current therapies, there is a clear clinical need for a novel peripheral nerve graft . Decellularised porcine peripheral nerves may represent a suitable material; however, they would require terminal sterilisation prior to use. The main aim of this study was to identify a sterilisation method which minimally impacted upon decellularised nerve extracellular matrix (ECM) structure, biochemical composition, biomechanical properties and biocompatibility. Peracetic acid (PAA) solution 0.1 % (v/v) caused disruption to the structure of the endoneurium and reductions in the intensity of antibody labelling for basement membrane components, particularly collagen IV (with increased severity after a 12 month storage period). Supercritical carbon dioxide (SCCO2) treatment (with an additive solution containing 13.5 - 18.5 % [v/v] PAA and 4.5 - 6 % [v/v] H2O2) under standard conditions induced similar effects to the histioarchitecture and significant alterations to tensile mechanical properties; processing of the tissue whilst submerged in phosphate-buffered saline appeared to protect against such effects. Treatment with gamma radiation (25 – 28 kGy) and E Beam (33 – 37 kGy) mediated retention of the decellularised nerve ECM structure, and changes to the localisation and intensity of labelling for basement membrane components were minimal compared with those observed following treatment with PAA solution or SCCO2 under standard conditions. However, gamma radiation caused the stiffness of the nerves to increase. Contact culture experiments did not yield evidence of cytotoxicity following any of the sterilisation methods; furthermore, the sterilised nerves did not induce any significant changes in the secretion of key cytokines by a murine macrophage cell line. These data indicate that E Beam could be an optimal sterilisation method for use with the decellularised nerves, notwithstanding preliminary results indicating that SCCO2 processing under submerged conditions may enable superior basement membrane preservation.

Item Type: Thesis (PhD)
Keywords: Peripheral nerve, decellularisation, sterilisation
Academic Units: The University of Leeds > Faculty of Engineering (Leeds) > School of Mechanical Engineering (Leeds) > Institute of Medical and Biological Engineering (iMBE)(Leeds)
Identification Number/EthosID: uk.bl.ethos.798033
Depositing User: James Daniel Rhys Holland
Date Deposited: 10 Feb 2020 13:52
Last Modified: 11 Mar 2020 10:54
URI: http://etheses.whiterose.ac.uk/id/eprint/25905

You do not need to contact us to get a copy of this thesis. Please use the 'Download' link(s) above to get a copy.
You can contact us about this thesis. If you need to make a general enquiry, please see the Contact us page.

Actions (repository staff only: login required)