OBJECTIVETo investigate the survival, growth and distribution of human amniotic epithelial cells (hAEC) after injected into injured rabbit vocal folds, in addition, to assess the ability of hAEC to affect the components of lamina propria extracellular matrix (ECM) and prevent vocal fold scarring.

METHODShAEC were isolated from human amnion and marked by Lenti-EGFP. Fifteen New Zealand rabbits were used for this experiment. EGFP-hAEC was injected into the left injured vocal folds in thirteen rabbits, and the contralateral thirteen vocal folds experienced an injured procedure only ("injured untreated control"), and four vocal folds were left as untreated controls. The survival, distribution, differentiation potential and secretion function of hAEC were examined by immunofluorescence method. HE staining and immunohistochemical staining were performed for the evaluation of collagen and fibronectin respectively.

RESULTShAEC showed a cobblestone-like growth. After implanted into the injured vocal folds, hAEC could survive in vocal fold lamina propria for 2 months. The immunofluorescence analysis showed the evidence of hAEC differentiation into muscle cells as well as secretion the ECM protein. Three months postoperatively, the density of collagen was higher in the injured untreated control folds than that in the injured vocal folds injected with hAEC and the untreated controls. Besides, the content of fibronectin in the injured untreated control group was significantly increased.

CONCLUSIONShAEC survived in the vocal folds lamina propria, and had the potentiality to differentiate into vocal folds tissue and secret some ECM components. The histological improvement caused by the injected cells demonstrate that hAEC had the ability to promote the repairment and regeneration of injured vocal folds.