Olfactory Derived Stem Cells Delivered in a Biphasic Conduit Promote Peripheral Nerve Repair In Vivo

Abstract

Peripheral nerve injury presents significant therapeutic challenges for recovery of motor and sensory function in patients. Different clinical approaches exist but to date there has been no consensus on the most effective method of treatment. Here, we investigate a novel approach to peripheral nerve repair using olfactory derived stem (ONS) cells delivered in a biphasic collagen and laminin functionalized hyaluronic acid based nerve guidance conduit (NGC). Nerve regeneration was studied across a 10-mm sciatic nerve gap in Sprague Dawley rats. The effect of ONS cell loading of NGCs with or without nerve growth factor (NGF) supplementation on nerve repair was compared to a cell-free NGC across a variety of clinical, functional, electrophysiological, and morphologic parameters. Animals implanted with ONS cell loaded NGCs demonstrated improved clinical and electrophysiological outcomes compared to cell free NGC controls. The nerves regenerated across ONS cell loaded NGCs contained significantly more axons than cell-free NGCs. A return of the nocioceptive withdrawal reflex in ONS cell treated animals indicated an advanced repair stage at a relatively early time point of 8 weeks post implantation. The addition of NGF further improved the outcomes of the repair indicating the potential beneficial effect of a combined stem cell/ growth factor treatment strategy delivered on NGCs. STEM CELLS TRANSLATIONAL MEDICINE 2017;6:1894-1904 SIGNIFICANCE STATEMENTPeripheral nerve injury affects millions of patients each year resulting in reduced quality of life, and billions of dollars in health care costs and lost work capacity. Surgical intervention with autografts work reasonably well for small lesions but for larger injuries, the functional outcomes are often unfavorable. Combining a surgical approach with contemporary developments in tissue engineering offers a potentially rewarding way forward. This study indicates that olfactory derived stem cells can have a regenerative effect on peripheral nerve repair in vivo when delivered on a novel biomaterial consisting of a collagen and laminin functionalized hyaluronic acid nerve guidance conduit.

A Physicochemically Optimized and Neuroconductive Biphasic Nerve Guidance Conduit for Peripheral Nerve Repair

“…Furthermore, directionality assessment of the axonal outgrowth suggested that the 3D microarchitecture of the luminal filler provided a neuroconductive substrate with the potential to guide axonal regeneration (Figure B). The in vivo evaluation of the biphasic NGC, which is described in detail in our recently published study, not only demonstrated its capacity to support functional repair, but also demonstrated the capacity of the filler to support cell delivery in order to enhance nerve repair …”

“…Collectively, the in vitro assessment of the biological response from a number of different cell types to the HyA luminal filler presented in this study, provides evidence to suggest that it has been developed to be neuroconductive, and shows the addition of laminin was a key determinant in this process. This optimized biphasic NGC has furthermore shown the ability to facilitate functional and morphological recovery as early as 8 weeks in a Sprague Dawley sciatic nerve defect model (10 mm), further highlighting its potential …”

Rat Olfactory Mucosa Mesenchymal Stem/Stromal Cells (OM-MSCs): A Characterization Study

“…Previous studies on OM-MSCs' secretome allowed to identify the production and secretion of bioactive molecules with a direct influence on neural differentiation, namely in the production and maturation of glial cells [31]. In addition, its clinical potential has already been tested in the field of experimental neurology, as in the treatment of neurodegenerative diseases of the central nervous system [32], hippocampal lesions [33,34], in the regeneration of the peripheral nerves and cranial nerves [35][36][37][38] and in cases of spinal cord trauma [39,40]. Its immune-suppressive effect over autoimmune diseases [41,42] and regenerative promotion in myocardial tissue a er infarct [43] and ischemic tissues [44] was also evaluated.…”

The Use of Genipin as an Effective, Biocompatible, Anti‐Inflammatory Cross‐Linking Method for Nerve Guidance Conduits

“…Among the various natural and synthetic biomaterials used for developing filled NGCs, collagen has been extensively used for both the inner and outer matrices due to its excellent biocompatibility, low antigenicity, porosity, biodegradability, and nontoxic degradation products 14–18. In our group, we have successfully developed collagen‐based scaffolds for several applications including bone,19–21 cartilage,22,23 heart valves,24 and peripheral nerves 25–28. We have previously shown that a biphasic NGC composed of a collagen‐based outer conduit and a neuroconductive hyaluronic acid/laminin based luminal filler26 facilitated morphological and functional recovery across a 10 mm rat sciatic nerve injury 25.…”

“…In our group, we have successfully developed collagen‐based scaffolds for several applications including bone,19–21 cartilage,22,23 heart valves,24 and peripheral nerves 25–28. We have previously shown that a biphasic NGC composed of a collagen‐based outer conduit and a neuroconductive hyaluronic acid/laminin based luminal filler26 facilitated morphological and functional recovery across a 10 mm rat sciatic nerve injury 25. This conduit also provided a platform for the controlled delivery of genes encoding for growth factors such as nerve growth factor (NGF) and glial derived neurotrophic factor (GDNF) and transcription factor c‐Jun 27.…”