Prolonged cold-preservation of nerve allografts

Abstract
The goal of this study was to determine the effect of varying durations of cold‐preservation on the immunogenicity of nerve allografts and their subsequent ability to facilitate neuroregeneration across a short nerve gap. Allografts preserved for 1, 4, and 7 weeks were compared to untreated allografts and isografts. There was a shift from an interferon‐γ–producing cellular response (untreated allografts) to an absence of response (7‐week cold‐preserved allografts and isografts). There were no detectable alloantibodies by flow cytometry. Histomorphometry distal to the graft showed robust regeneration in the isograft and 7‐week cold‐preserved groups when compared to the untreated allograft group. Increasing duration of cold‐preservation diminished the cellular immune response. This cold‐preservation does not preclude subsequent nerve regeneration across a short nerve graft. Prolonged cold‐preservation of nerve allograft tissue could serve as a means to produce unlimited graft material for use in peripheral nerve reconstruction. Muscle Nerve, 2005