Evaluating Feasibility of Human Tissue Engineered Respiratory Epithelium Construct as a Potential Model for Tracheal Mucosal Reconstruction

Abstract

The normal function of the airway epithelium is vital for the host’s well-being. Conditions that might compromise the structure and functionality of the airway epithelium include congenital tracheal anomalies, infection, trauma and post-intubation injuries. Recently, the onset of COVID-19 and its complications in managing respiratory failure further intensified the need for tracheal tissue replacement. Thus far, plenty of naturally derived, synthetic or allogeneic materials have been studied for their applicability in tracheal tissue replacement. However, a reliable tracheal replacement material is missing. Therefore, this study used a tissue engineering approach for constructing tracheal tissue. Human respiratory epithelial cells (RECs) were isolated from nasal turbinate, and the cells were incorporated into a calcium chloride-polymerized human blood plasma to form a human tissue respiratory epithelial construct (HTREC). The quality of HTREC in vitro, focusing on the cellular proliferation, differentiation and distribution of the RECs, was examined using histological, gene expression and immunocytochemical analysis. Histological analysis showed a homogenous distribution of RECs within the HTREC, with increased proliferation of the residing RECs within 4 days of investigation. Gene expression analysis revealed a significant increase (p < 0.05) in gene expression level of proliferative and respiratory epithelial-specific markers Ki67 and MUC5B, respectively, within 4 days of investigation. Immunohistochemical analysis also confirmed the expression of Ki67 and MUC5AC markers in residing RECs within the HTREC. The findings show that calcium chloride-polymerized human blood plasma is a suitable material, which supports viability, proliferation and mucin secreting phenotype of RECs, and this suggests that HTREC can be a potential candidate for respiratory epithelial tissue reconstruction.

Surgical Innovations in Tracheal Reconstruction: A Review on Synthetic Material Fabrication

“…By isolation, respiratory epithelial cells from the nasal turbinate are incorporated into calcium chloride polymerised blood plasma to produce human tissue respiratory epithelial construct (HTREC). After gene expression analysis, Ki67 (a proliferative marker) and MUC5AC (a mucin-secreting marker) both had significant increases in gene expression levels after four days, highlighting the viability of HTREC as an option for respiratory epithelial reconstruction [43]. When autologous nasal epithelial sheets were incorporated into a partially decellularised scaffold in rabbits, the cell sheets enhanced epithelial regeneration and the transplanted patches were wholly incorporated into the trachea after two months [44].…”

Wet-adhesive γ-PGA/ε-PLL hydrogel loaded with EGF for tracheal epithelial injury repair

“…Extraction and culture of TECs and fibroblasts. Tracheal epithelial cells and fibroblasts were extracted and cultured as described previously, 32 and modified slightly. New Zealand White rabbits (3 months old, male; provided by the Shanghai Jiaotong University Agricultural and Student Experimental Practice Facility Co., Ltd) were euthanized using intravenous sodium pentobarbital (100 mg kg À1 ), their tracheae were removed, and the samples were washed three times with PBS (Gibco) containing 1% penicillinstreptomycin-amphotericin (Gibco).…”

Role of Biomaterials in the Development of Epithelial Support in 3D In Vitro Airway Epithelium Development: A Systematic Review

“…Human plasma [33] • Human tissue respiratory epithelial construct (HTREC) • Respiratory epithelial cells (RECs)…”