Page 12 - JCTR-10-2

106 Dinaki et al. | Journal of Clinical and Translational Research 2024; 10(2): 99-111
returned to school [2]. Subsequently, the 4-year follow-up study and vital functions (e.g., breathing and swallowing) and improved
reportedly validated the long-term viability of a decellularized the patient’s quality of life. However, the complexity of restoring
tissue-engineered trachea within the child [93]. In the second otorhinolaryngological functions requires further research to
study, a 15-year-old girl with severe tracheal stenosis was treated refine the techniques used in regenerative medicine.
with a tissue-engineered decellularized tracheal graft seeded with
stem cells [94]. A decellularized tracheal allograft, seeded with Acknowledgments
autologous respiratory epithelial cells and MSCs, was applied. None.
Early findings were promising, but a critical incident speculated
as an intrathoracic hemorrhage, resulted in rapid airway blockage Funding
and her subsequent death 3 weeks after the transplantation. Not applicable.
In addition, synthetic scaffolds have been utilized for tracheal
restoration. Omori et al. were the first to use regenerative procedures Conflict of Interest
to restore the trachea of a thyroid cancer patient [95]. A polypropylene
mesh tube coated with a collagen sponge was utilized as a tissue The authors declare no conflicts of interest with regard to the
scaffold. The process included right hemithyroidectomy, trachea content presented in this work.
resection, and scaffold-assisted tracheoplasty. The right side of the Ethics Approval and Consent to Participate
three trachea ring segments was removed, and the trachea defect was
bridged by suturing the scaffold material. In 2008, Omori et al. also Not applicable.
utilized similar synthetic implants in four patients to successfully Consent for Publication
repair their larynx and/or trachea [96].
In animal studies involving aortic allograft, de novo regeneration Not applicable.
of cartilage was observed within the graft, as well as renewal of
ciliated epithelium in the graft lumen [97,98]. This was followed by Availability of Data
a clinical trial with six patients [99]. It was reported that the tracheal Not applicable.
replacement with aortic allografts was successful in four of the
six patients [99]. In a separate study, five patients who underwent References
trachea reconstruction with human cryopreserved (−80°C) aortic [1] Vats A, Birchall M. Stem Cells and Regenerative Medicine:
allografts all had favorable outcomes [100]. A similar study Potentials and Realities for Rhinology. Rhinology
reported that thawing cryopreserved aortic allografts enabled 2010;48:259-64.
viable donor cells to release cytokines and growth factors [101].
Many animal studies have been performed with synthetic doi: 10.4193/Rhin10.007
3D-printed scaffolds to determine the materials with the best [2] Elliott MJ, De Coppi P, Speggiorin S, Roebuck D,
mechanical properties and also evaluate the effectiveness of graft Butler CR, Samuel E, et al. Stem-Cell-Based, Tissue
seeding with autologous cells [102-106]. Kim et al. studied the Engineered Tracheal Replacement in a Child: A 2-Year

transplantation of a 3D-printed tracheal graft mixed with iPSCs Follow-Up Study. Lancet 2012;380:994-1000.
and chondrocytes in a rabbit model [107]. In the study, a tissue- doi: 10.1016/S0140-6736(12)60737-5
engineered artificial trachea was successfully transplanted into [3] Hu Z, Ulfendahl M. The Potential of Stem Cells for the
a rabbit model with a 1.5 cm segmental trachea defect. There Restoration of Auditory Function in Humans. Regen Med
were no signs of granulation ingrowth in the tracheal lumen, and 2013;8:309-18.
epithelium and neocartilage successfully formed at the defect doi: 10.2217/rme.13.32
sites. According to the research findings by Choi et al., a coating [4] Salgado AJ, Reis RL, Sousa NJ, Gimble JM. Adipose
of HA on a hydrophobic tracheal scaffold could improve the Tissue Derived Stem Cells Secretome: Soluble Factors and
adherence of MSCs and tracheal regeneration [108]. In contrast, Their Roles in Regenerative Medicine. Curr Stem Cell Res
Pepper et al. used synthetic tissue-engineered tracheas in an ovine Ther 2010;5:103-10.
model. However, it was reported that the transplanted tracheas doi: 10.2174/157488810791268564
could not induce optimal epithelialization and neovascularization,
and the process led to further complications, such as inflammation [5] McPhail MJ, Janus JR, Lott DG. Advances in Regenerative
and infection [103]. Hence, future studies should focus on scaffold Medicine for Otolaryngology/Head and Neck Surgery.
modulation that would accelerate epithelialization and avoid graft BMJ 2020;369:m718.
devascularization that could lead to graft infection and necrosis. doi: 10.1136/BMJ.M718
[6] Tabata Y. Tissue Regeneration Based on Growth Factor
6. Conclusion Release. Tissue Eng 2003;9 Suppl 1:S5-15.

Regenerative medicine is rapidly progressing in the field of doi: 10.1089/10763270360696941
otorhinolaryngology and has reportedly restored hearing, voice, [7] Mitchell AC, Briquez PS, Hubbell JA, Cochran JR.
DOI: https://doi.org/10.36922/jctr.22.00151