World’s first trachea transplant marks new era in stem cells

20 February 2012

The technique of extracting stem cells from knee cartilage created in the lab was first pioneered by the University of Bristol’s School for Cellular and Molecular Medicine in 2005, when Professor Anthony Hollander and his team successfully grew human cartilage from a patient’s own stem cells. 

Three years later, Professor Hollander was approached by Professor Paulo Macchiarini, Head of Respiratory Surgery at the Hospital Clinic de Barcelona, with the idea of adapting the technique to save the life of a woman who had been suffering with severe breathing difficulties caused by a rare form of tuberculosis. 

The team went on to create a tissue-engineered trachea using stem cells taken from the patient, which was scaffolded on to a donor trachea and used to replace that of the patient, mother of two, Claudia Castillo.

The case represented a historic milestone, paving the way for less invasive surgical techniques and demonstrating the importance of basic scientific research to translational medicine.

“This successful treatment manifestly demonstrates the potential of adult stem cells to save lives,” said Professor Hollander, Arthritis Research Campaign Professor of Rheumatology and Tissue Engineering.

Professor Hollander was initially hesitant about the possibility of applying a technique that had, until then, only been proven in the lab.  Yet the ambition, clinical expertise and commitment of a multinational team combined to have dramatic results, overcoming logistical problems that at one stage, threatened to prevent the transportation of the bioengineered trachea across continents,

In the Bristol lab, stem cells taken from the patient’s bone marrow were grown and matured into cartilage cells using an adapted method originally devised in Bristol for treating osteoarthritis. While in Spain, a seven-centimetre tracheal segment donated by a transplant donor was completely decellularised to leave only a scaffold of collagen.

The donor trachea was then seeded with cartilage cells on the outside, using a novel bioreactor developed at Italy’s Politecnico di Milano that incubates cells, allowing them to migrate into the tissue.  In order to replicate the lining of the trachea, epithelial cells were then seeded onto the inside of the trachea. 

Days later, Claudia underwent surgery to replace her left main bronchus with the seeded graft.  Within four days of the transplant, the graft was almost indistinguishable from adjacent normal bronchi and ten days after the operation, Claudia – who otherwise faced losing her lung - was discharged from hospital.

The tissue engineering techniques pioneered by Professor Hollander’s team have already been successfully commercialised by University of Bristol spin-out company Azellon, which raised £1.6 million to fund trials in cell bandaging technology, a method of cartilage repair using patients’ stem cells.

Please contact Aliya Mughal for further information.