Differentiation potential of the cells in the macula flava of the human vocal fold mucosa.

The latest research suggests cells in the maculae flavae located at both ends of the lamina propria of the human vocal fold mucosa have stemness. This study investigated the differentiation potential of the cells in the maculae flavae of the human vocal fold mucosa. Four normal human adult vocal folds from surgical specimens were used. After extraction of the anterior maculae flavae located at the anterior end of the lamina propria of the human vocal fold mucosa under microscope, the maculae flavae were minced, cultured and proliferated in mesenchymal stem cell growth medium and morphological features were assessed. Cell surface markers were detected using flow cytometry. Cell differentiation into adipogenic, chondrogenic and osteogenic lineages was performed. Cell's differentiation potential was assessed using a human pluripotent stem cell functional identification kit and immunohistochemistry. Subcultured cells formed a colony-forming unit. Subcultured cells expressed CD90, CD105 and CD73 and lacked expression of CD45, CD34, CD11b, CD19 and HLA-DR. They differentiated into adipogenic, chondrogenic and osteogenic lineages. Consequently, the cell features in the maculae flavae meet the minimal criteria defining mesenchymal stromal cells. In addition, subcultured cells differentiated into ectoderm, mesoderm and endoderm and expressed stage-specific embryonic antigen 3 (SSEA-3). The results of this study are consistent with the hypothesis that the cells in the maculae flavae in the lamina propria of the human vocal fold mucosa are putative stem cells.