Long-term changes to in vitro preserved bioengineered human trachea and their implications for decellularized tissues

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Bioengineered tissues for transplantation require long-term viability and function.
• Evaluating the stability of decellularized human tissue scaffolds is crucial for clinical application.
• The extracellular matrix (ECM) integrity is vital for tissue scaffold performance.

Purpose of the Study:

• To assess the in vitro degradation of decellularized human trachea scaffolds over a one-year storage period.
• To compare the structural, mechanical, and angiogenic properties of stored scaffolds against baseline values.
• To determine the suitability of stored scaffolds for long-term tissue engineering applications.

Main Methods:

• Human tracheas were decellularized and stored in phosphate-buffered saline (PBS) at 4°C with antibiotics for one year.
• Structural analysis focused on extracellular matrix architecture, including collagen and elastic fibers.
• Mechanical testing evaluated scaffold strength and elasticity.
• Angiogenic properties were assessed to determine potential for new blood vessel formation.

Main Results:

• Stored decellularized tracheas exhibited significant degradation of the ECM, particularly collagen and elastic fibers.
• A notable decrease in mechanical strength and angiogenic potential was observed after one year of storage.
• A natural cross-linking agent did not improve the mechanical alterations or prevent ECM deterioration.

Conclusions:

• Human decellularized trachea scaffolds stored for one year in PBS at 4°C are unsuitable for lifelong tissue engineering grafts due to ECM degradation.
• Observed in vitro degradation may be exacerbated in vivo, posing risks for long-term transplanted tissues.
• Further pre-clinical evaluation is essential to assess the clinical relevance of scaffold degradation for long-term implantation.