Reconstruction of Multiple Facial Nerve Branches Using Skeletal Muscle-Derived Multipotent Stem Cell Sheet-Pellet Transplantation

Abstract

Head and neck cancer is often diagnosed at advanced stages, and surgical resection with wide margins is generally indicated, despite this treatment being associated with poor postoperative quality of life (QOL). We have previously reported on the therapeutic effects of skeletal muscle-derived multipotent stem cells (Sk-MSCs), which exert reconstitution capacity for muscle-nerve-blood vessel units. Recently, we further developed a 3D patch-transplantation system using Sk-MSC sheet-pellets. The aim of this study is the application of the 3D Sk-MSC transplantation system to the reconstitution of facial complex nerve-vascular networks after severe damage. Mouse experiments were performed for histological analysis and rats were used for functional examinations. The Sk-MSC sheet-pellets were prepared from GFP-Tg mice and SD rats, and were transplanted into the facial resection model (ST). Culture medium was transplanted as a control (NT). In the mouse experiment, facial-nerve-palsy (FNP) scoring was performed weekly during the recovery period, and immunohistochemistry was used for the evaluation of histological recovery after 8 weeks. In rats, contractility of facial muscles was measured via electrical stimulation of facial nerves root, as the marker of total functional recovery at 8 weeks after transplantation. The ST-group showed significantly higher FNP (about three fold) scores when compared to the NT-group after 2–8 weeks. Similarly, significant functional recovery of whisker movement muscles was confirmed in the ST-group at 8 weeks after transplantation. In addition, engrafted GFP+ cells formed complex branches of nerve-vascular networks, with differentiation into Schwann cells and perineurial/endoneurial cells, as well as vascular endothelial and smooth muscle cells. Thus, Sk-MSC sheet-pellet transplantation is potentially useful for functional reconstitution therapy of large defects in facial nerve-vascular networks.

Regeneration of Transected Recurrent Laryngeal Nerve Using Hybrid-Transplantation of Skeletal Muscle-Derived Stem Cells and Bioabsorbable Scaffold

“…In addition to the cell restriction ability of the present hybrid transplantation system, the transplanted/engrafted cells sufficiently differentiated into axon-supportive Schwann cells, perineurial/endoneurial cells, skeletal muscle cells, and endothelial cells, as reported previously [ 6 , 8 , 9 ]. As a result of this cell differentiation, axons of the growth cone of RLN extended and re-connected to target axons in the distal stump, through the support of Schwann cells, perineurium/endoneurium, and blood vessel networks ( Figure 5 ), and achieved favorable functional recovery ( Figure 2 ), as reported previously [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. In this regard, it is also apparent that this hybrid system does not interrupt any cell differentiation and tissue reconstitution ability of Sk-MSCs.…”

“…We have proposed and demonstrated the significant therapeutic capacity of skeletal muscle-derived multipotent stem cell (Sk-MSC) and human skeletal muscle-derived stem cell (Sk-SC) transplantation to the transected sciatic nerve, showing high numerical and functional recovery [ 6 , 7 ]. The regenerative capacity of mouse Sk-MSCs/human Sk-SCs (i.e., differentiation into Schwann cells, perineurial/endoneurial cells, vascular pericytes, endothelial cells, and smooth muscle cells) has been demonstrated in various tissue circumstances such as in the sciatic nerve [ 6 , 7 ], damaged skeletal muscle [ 8 , 9 , 10 ], facial nerve network [ 11 ], urethral sphincter [ 12 , 13 ], bladder wall [ 14 ], and the nerve-vascular bundle [ 15 ]. Furthermore, we recently developed a hybrid-transplantation method for Sk-MSCs and bioabsorbable polyglyconate (PGA) felt and achieved significant innervation and vascularization in the bronchial stump [ 16 ].…”

Peripheral Nerve Regeneration Using a Cytokine Cocktail Secreted by Skeletal Muscle-Derived Stem Cells in a Mouse Model

“…Furthermore, in previous studies, Sk-MSCs consistently exerted the synchronized tissue reconstitution ability of the nerve–muscle–blood vessel unit in the skeletal muscle [ 18 , 32 , 33 ], muscle–tendon unit [ 34 ], and in a variety of other tissues, i.e., around the urinary tract [ 35 , 36 , 37 ], bladder wall [ 38 ], bronchial stump [ 39 ], facial nerve [ 40 ], and recurrent laryngeal nerve [ 41 ]. Therefore, it is also possible that this cytokine cocktail treatment may be available for a variety of tissue reconstitution therapies as a tissue regeneration facilitation agent.…”

Dental and Nondental Stem Cell Based Regeneration of the Craniofacial Region: A Tissue Based Approach

“…The resulting SK-mSC sheets were then centrifuged to form a 3D pellet. Saito et al also opted to evaluate the pellets to regenerate a facial resection model, consisting of a “large facial nerve-blood vessel network deficit” encompassing both the buccal and zygomatic branches of the facial nerve [ 96 ]. The engrafted construct bridged the defect regenerating functioning myelinated axons along with supportive cell types.…”

“…SK-mSCs were also found to have an angiogenic propensity generating smooth muscle cells and endothelial cells. Physiological nerve bridging without specific guidance was believed to be due to the spatial release of neurotrophic factors by resected stumps during early SK-mSC differentiation [ 96 ]. This regenerative model seems to hold huge promise in cases of craniofacial cancers.…”