Cell origin in the macula flava of the human newborn vocal fold.

BACKGROUND There is growing evidence to suggest that cells in the maculae flavae are tissue stem cells of the human vocal fold and maculae flavae are a stem cell niche. METHODS Three newborn vocal folds were investigated. Immunoreactivity to antibodies directed to cytokeratin, desmin, glial fibrillary acidic protein, vimentin, cluster of differentiation 34, cluster of differentiation 45, collagen type I, telomerase reverse transcriptase, SOX17 and stage-specific embryonic antigen 3 was investigated. RESULTS The cells in the newborn maculae flavae expressed haematopoietic markers (cluster of differentiation 34, cluster of differentiation 45) and collagen type I, which are the major makers of bone marrow derived circulating fibrocytes. The cells expressed epithelium, muscle, neural and mesenchymal cell associated proteins, and endodermal marker, indicating that they are undifferentiated and express proteins of all three germ layers. The cells also expressed stage-specific embryonic antigen 3 and telomerase reverse transcriptase. CONCLUSION The cells in the newborn maculae flavae are undifferentiated cells arising from the differentiation of bone marrow cells. The results of this study are consistent with the hypothesis that the cells in maculae flavae are tissue stem cells.