In vivo regeneration of rat laryngeal cartilage with mesenchymal stem cells derived from human induced pluripotent stem cells via neural crest cells

The laryngotracheal cartilage is a cardinal framework for the maintenance of the airway for breathing, which occasionally requires reconstruction. Because hyaline cartilage has a poor intrinsic regenerative ability, various regenerative approaches have been attempted to regenerate laryngotracheal cartilage. The use of autologous mesenchymal stem cells (MSCs) for cartilage regeneration has been widely investigated. However, long-term culture may limit proliferative capacity. Human-induced pluripotent stem cell-derived MSCs (iMSCs) can circumvent this problem due to their unlimited proliferative capacity. This study aimed to investigate the efficacy of iMSCs in the regeneration of thyroid cartilage in immunodeficient rats. Herein, we induced iMSCs through neural crest cell intermediates. For the relevance to prospective future clinical application, induction was conducted under xeno-free/serum-free conditions. Then, clumps fabricated from an iMSC/extracellular matrix complex (C-iMSC) were transplanted into thyroid cartilage defects in immunodeficient rats. Histological examinations revealed cartilage-like regenerated tissue and human nuclear antigen (HNA)-positive surviving transplanted cells in the regenerated lesion. HNA-positive cells co-expressed SOX9, and type II collagen was identified around HNA-positive cells. These results indicated that the transplanted C-iMSCs promoted thyroid cartilage regeneration and some of the iMSCs differentiated into chondrogenic lineage cells. Induced MSCs may be a promising candidate cell therapy for human laryngotracheal reconstruction

Laryngeal Cartilage Regeneration of Nude Rats by Transplantation of Mesenchymal Stem Cells Derived from Human-Induced Pluripotent Stem Cells

Previous studies transplanted human-induced pluripotent stem cells (hiPSCs)-derived mesenchymal stem cells (iMSCs) into thyroid cartilage defect of X-liked severe combined immunodeficiency (X-SCID) rats and confirmed transplanted cell survival and cartilage regeneration. Thus, this study aimed to investigate the contribution of iMSC transplantation to thyroid cartilage regeneration of nude rats. iMSCs were induced from hiPSCs via a neural crest cell lineage. Then, clumps formed from an iMSC/extracellular matrix complex were transplanted into thyroid cartilage defects in nude rats. The larynx was removed and histological and immunohistochemical analyses were performed 4 or 8 weeks after the transplantation. Human nuclear antigen (HNA)-positive cells were observed in 11 of 12 (91.7%) rats, which indicated that transplanted iMSCs survived in thyroid cartilage defects in nude rats. HNA-positive cells co-expressed SOX9, and type II collagen was identified around HNA-positive cells in 8 of 12 rats (66.7%), which indicated cartilage-like regeneration. Cartilage-like regeneration in nude rats in this study was comparable to the previous report on X-SCID rats (HNA-positive cells were observed in all 14 rats and cartilage-like regeneration was observed in 10 of 14 rats). This result suggests that nude rats could be an alternative to X-SCID rats in thyroid cartilage regeneration experiments using iMSCs, and this nude rat cartilage transplantation model may develop cartilage regeneration research concerning fewer problems such as infection due to immunosuppression

塩基性線維芽細胞増殖因子徐放性コラーゲンゼラチンスポンジを用いた声帯瘢痕の再生治療

Final publication is available at http://onlinelibrary.wiley.com/doi/10.1002/term.2060/abstract;jsessionid=F0849D98381EEF9E83401A02B9042F4D.f04t02京都大学0048新制・課程博士博士(医学)甲第19602号医博第4109号新制||医||1014(附属図書館)32638京都大学大学院医学研究科医学専攻(主査)教授 別所 和久, 教授 伊佐 正, 教授 川口 義弥学位規則第4条第1項該当Doctor of Medical ScienceKyoto UniversityDFA

Adipose-derived stem cells versus bone marrow-derived stem cells for vocal fold regeneration.

[Objectives/Hypothesis]Vocal fold scarring presents therapeutic challenges. Recently, cell therapy with mesenchymal stromal cells has become a promising approach. The aim of this study was to compare the therapeutic potential of adipose-derived stem cells (ASC) with bone marrow-derived stem cells (BMSC) for vocal fold regeneration. [Study Design]Prospective animal experiments with controls. [Methods]The vocal folds of Sprague-Dawley rats were unilaterally injured. Two months after injury, rats were treated with a local injection of ASC (ASC group), BMSC (BMSC group), or saline (sham-treated group). The GFP-labeled ASC and BMSC were extracted from CAG-EGFP rats. Larynges were harvested for histological and immunohistochemical examinations 1 and 3 months posttransplantation and for quantitative real-time polymerase chain reaction (PCR) 1 month posttransplantation. [Results] After 1 month, no surviving cells from the transplant were detected. Histological examination showed significantly increased hyaluronic acid (HA) and decreased dense collagen deposition in both ASC and BMSC groups compared to shams 1 and 3 months after treatment. Real-time PCR revealed that hyaluronan synthase 1 (Has1) and Has2 were upregulated in only the ASC group compared with the sham-treated group. Fibroblast growth factor 2 (basic) (Fgf2), hepatocyte growth factor (Hgf) and Has3 were upregulated in both cell transplantation groups. ASC seemed to upregulate Hgf more than did BMSC. [Conclusions]The regenerative effects of ASC and BMSC transplantation were found to be similar for the restoration. It is suggested that ASC might have more potential because of better recovery of HA, a superior antifibrotic effect, and the upregulation of Hgf

Multidimensional Analysis on the Effect of Vocal Function Exercises on Aged Vocal Fold Atrophy.

Age-related voice change is characterized as weak, harsh, and breathy. These changes are caused by histologic alteration of the lamina propria of the vocal fold mucosa as well as atrophy of the thyroarytenoid muscle. Several therapeutic strategies involving laryngeal framework surgery and injection laryngoplasty have been tried, but effects have been limited. Vocal function exercises (VFE) have been used to treat age-related vocal fold atrophy although the effectiveness has been shown with limited analysis. The present study aims to determine the effectiveness of VFE for the treatment of aged atrophy using multidimensional analysis

Intraoperative computed tomography imaging for laryngoplasty

[Objectives] Intraoperative cone beam computed tomography (CBCT) imaging has the potential to facilitate the surgical procedure. The current preliminary retrospective chart review investigated the benefits of intraoperative CBCT during laryngoplasty. [Method] This study examined 26 cases that underwent intraoperative CBCT imaging during laryngoplasty, with one patient who counted twice due to first and revision surgery. The visual quality of structures of interest (glottal shape, thyroid cartilage, arytenoid cartilage, and implants) was determined using intraoperative CBCT during laryngoplasty. Each patient also underwent an aerodynamic assessment. [Results] CBCT provided unique information, such as surgical landmarks in severe scarring, the subglottal shape, and the rotation angle of the arytenoid cartilage during arytenoid adduction. Nonetheless, 26.9% (7 of 26) of cases were affected by motion artifact, due to the long acquisition time. When motion artifact-negative cases were evaluated, 100% of glottal shape and more than 89% of thyroid cartilage were well visualized. All arytenoids were well-visualized in patients ≥ 50 years of age and without motion artifact, while CBCT failed to visualize the arytenoids in 2 of 4 patients who were < 50 years, due to the lack of calcifications. After medialization surgery, the yields of improved maximal phonation times (MPTs) in the motion artifact-negative and -positive groups were 8.7 sec and 3.4 sec, respectively (p = 0.032; Welch's t test). This comparison indicates intraoperative CBCT would contribute in MPT improvement, if CBCT is taken in measurable quality. [Conclusion] The potential benefits of intraoperative CBCT during laryngoplasty were demonstrated. A corollary, prospective study is warranted to further confirmation

Voice Outcome in Patients Treated With Endoscopic Laryngopharyngeal Surgery for Superficial Hypopharyngeal Cancer

Objectives Endoscopic laryngopharyngeal surgery (ELPS) is a minimally invasive transoral surgery that was developed to treat superficial larygo-pharyngeal cancer, in which a mucosal lesion is resected transorally while preserving deeper structures by subepithelial injection. The purpose of this retrospective study is to evaluate voice outcome in patients who underwent ELPS for superficial hypopharyngeal cancer. As important structures in producing voice, such as intrinsic laryngeal muscles, their fascia, and recurrent laryngeal nerve, are located in the medial side of the piriform sinus and the postcricoid region of the hypopharynx, we focused on patients with cancer lesions involving these regions. Methods From April 2010 to March 2011, 25 consecutive patients with superficial laryngopharyngeal cancer were treated with ELPS at Kyoto University Hospital. Among the 25 patients, 11 patients with cancer lesions on the medial side of the piriform sinus or the postcricoid area were studied. Preoperative and postoperative voice functions including maximum phonation time (MPT), mean flow rate (MFR), jitter, shimmer, soft phonation index (SPI), and noise-to-harmonic ratio (NHR), were compared retrospectively. Results Five of 11 cancer lesions had submucosal invasion and no lesion had invaded the muscular layer pathologically. T stage was classified as Tis in 5 cases, T1 in 4 cases, and T2 in 2 cases. All lesions involved the medial side of the piriform sinus and 2 also involved the postcricoid area. Vocal fold movement was normal in all cases after the surgery. Average preoperative and postoperative values for MPT, MFR, jitter, shimmer, SPI, and NHR, were 22.7 seconds and 23.4 seconds, 165 mL/sec and 150 mL/sec, 1.53% and 1.77%, 3.82% and 5.17%, 35.5 and 36.6, and 0.13% and 0.14%, respectively. There was no statistical difference between preoperative and postoperative data for all values examined. Conclusion ELPS is useful in preserving voice function in the treatment of superficial hypopharyngeal cancer. Preserving the deeper structures including intrinsic muscles and their fascia may be important for preserving voice function as long as the lesions are superficial

Effect of AST on age-associated changes of vocal folds in a rat model.

[Objectives/Hypothesis]Reactive oxygen species (ROS) are associated with aging. Astaxanthin (AST) is a strong antioxidant and has been reported to prevent various ROS-induced diseases. In the current study, we investigated the effect of AST on age-associated histological and mRNA changes of vocal folds. [Study Design]Prospective animal experiment with control. [Methods]Six-month-old Sprague-Dawley rats were fed on a normal powder diet with 0.01% (w/w) AST (aged AST-treated group) or without AST (aged sham-treated group). After 12 months of feeding, the larynges were harvested for histology, immunohistochemical detection of 4-hydroxy-2-nonenal (4-HNE), and quantitative real-time polymerase chain reaction for basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF). Thirteen-week-old rats were used as a young control group (young group). [Results]The expression of 4-HNE, an oxidative stress marker, significantly increased in the two aged groups compared with the young group. Histological examination showed that the deposition of hyaluronic acid in the lamina propria (LP) was significantly reduced in the aged sham-treated group compared with the young group, but no significant difference was observed between the aged AST-treated group and the young group. There were no significant differences in the mRNA expression of bFGF and HGF between the aged AST-treated group and the young group, although the expression of these genes was significantly reduced in the aged sham-treated group as compared with the young group. [Conclusions]These results suggest that AST has the potential to attenuate age-associated changes of vocal folds