The first operation for transplantation of a tissue-engineered airway has been successful, and has massively improved the quality of life of the 30-year-old Colombian female recipient, a mother of two, who needed the transplant after contracting tuberculosis.
These pioneering results are reported in an article published in The Lancet. The work was done by a team from four institutions: Hospital Clínic of Barcelona ( Universitat de Barcelona ), Spain, University of Bristol, UK, Politecnico di Milano, Italy, and University of Padua, Italy, and was led by Paolo Macchiarini ( Hospital Clínic of Barcelona ).
The loss of a normal airway is devastating, and attempts to replace large airways have met with serious problems, such as graft necrosis, lethal bleeding, and severe and life-threatening infections.
Pre-requisites for a tissue-engineered replacement are a suitable matrix, cells, ideal mechanical properties, and the absence of antigenicity ( rejection ).
The team removed the cells from a human donor trachea, principally because these cells have transplant rejection antigens. The decellularised trachea was then readily colonised with cartilage cells ( chondrocytes ) derived from the patient's own stem cells, and epithelial cells taken from a healthy part of her trachea.
This graft was then used to replace the recipient's left main bronchus, which connects the main windpipe ( trachea ) to the left lung.
Her own left bronchus had been damaged by an irreversible, end-stage collapse ( malacia ).
The recipient had no complications from the operation and was discharged from hospital on the 10th postoperative day. She has remained well since, and is able to walk up two flights of stairs, walk 500 m without stopping, and, perhaps most importantly, care for her children.
The graft had a normal appearance and properties at 4 months, and the patient had no anti-donor antibodies and did not need to take immunosuppressive drugs.
The graft also developed its own blood supply, with active bleeding within 30 days.
The results have shown that a cellular, tissue-engineered airway can be produced with mechanical properties that allow normal functioning, and which is free from the risks of rejection.
This patient provides new evidence that autologous cells combined with appropriate biomaterials might provide, in future, successful functional solutions for serious clinical disorders. ( Xagena )
Source: The Lancet, 2008