Biocompatibility Studies on Acellular Tracheae

Objective: The purpose of this study was to obtain acellular matrices from the tracheae of rabbits and SD rats, and to investigate their biocompatibility as a primary step toward developing a tissue-engineering artificial salivary gland organoid.

Methods: A modified ‘detergent and enzyme link' extraction procedure was performed to remove cells from SD rats' and rabbits' tracheae. The histology, topography of inner surfaces, and biocompatibility were studied on both acellular tracheae.

Results: Histological findings in the acellular tracheae (hematoxylin and eosin staining): Epithelium and mixed glands were completely removed after detergent treatment. Scanning electron microscopy findings of the inner surface of the acellular tracheae showed regular rough pits. After 12 weeks' implantation under the cheek skin of SD rats, acellular tracheae were infused around tissues, and new vessel formation could be found. We also found that the number of submandibular gland cells (SSG) attached to two kinds of acellular tracheae scaffold was much more than on PGA films. Statistical differences were found between two kinds of acellular tracheae matrices and PGA (P < 0.05). Better biocompatibility than with PGA film was also confirmed by Metabolic Activity Test (MTT Assay) and amylase activities assay.

Conclusion: Acellular tracheae matrices of SD rats and rabbits made in our laboratory could be used as scaffolds in the study of a tissue-engineering artificial salivary gland organoid.