Novel murine xenograft model for the evaluation of stem cell therapy for profound dysphagia.

OBJECTIVES/HYPOTHESIS: Dysphagia is common and costly. Treatments are limited and innovative therapies are required. The tongue is essential for safe, effective swallowing and is a natural target for regenerative therapy. Muscle-derived stem cells (MDSCs) hold potential to restore dynamic function, and their application in the damaged tongue is appealing. We examined the safety and efficacy of human MDSC implantation into a novel mouse tongue model. STUDY DESIGN: Animal study. METHODS: Adult immune-deficient mice were randomized to surgical (hemiglossectomy) and nonsurgical groups. Animals underwent lingual injection of human MDSCs or saline (control). Groups were followed for 12 weeks. The primary outcome was MDSC survival measured by an in vivo imaging system (IVIS). Secondary outcomes included animal survival and weight. Comparisons were made using a Mann-Whitney U test with an α of .05. RESULTS: Human MDSCs survived to the endpoint demonstrating 132% ± 465% and 15% ± 11% bioluminescence by IVIS at 12 weeks in hemiglossectomy and nonsurgical groups, respectively. All but one animal (hemiglossectomy with saline injection) survived to the study endpoint. Mean weight increased from baseline in all groups, with the greatest change observed in hemiglossectomy mice with MDSC injection (baseline 24.5 g ± 3.9 g; delta 5.9 g ± 4.6 g), exceeding the weight gain seen in surgical control mice (baseline 24.9 g ± 4.2 g, delta 2.7 g ± 1.4 g) (P = .04). CONCLUSIONS: MDSCs exhibited over 100% survival at 3 months when injected into an immune-deficient hemiglossectomy mouse model. Tongue-injured animals injected with MDSCs exhibited superior weight gain after hemiglossectomy than control animals (P < .05). These data support further investigation into the use of autologous MDSCs as a potential treatment for dysphagia secondary to tongue weakness and fibrosis LEVEL OF EVIDENCE: NA Laryngoscope, 127:E359-E363, 2017.

Human Myoblast and Mesenchymal Stem Cell Interactions Visualized by Videomicroscopy.

Muscle-derived progenitor cell (myoblast) therapy has promise for the treatment of denervated, weakened, and fibrotic muscle. The best methods for injecting myoblasts to promote fusion and retention have yet to be determined, however. Mesenchymal stem/stromal cells have also been reported to have beneficial effects in restoring damaged tissue, through increasing vascularization and reducing inflammation. The interactions between human primary skeletal myoblasts and bone marrow-derived mesenchymal stem/stromal cells were examined using time-lapse images put into video format. Of interest, there is a high degree of cell-to-cell interaction with microparticles transferring between both cell types, and formation of nanotubules to bridge cytoplasmic contents between the two types of cell. This model provides an in vitro platform for examining mechanisms for cell-to-cell interaction preceding myoblast fusion.