Airway Transplant Aided by Stem Cells a Medical First

By Amanda Gardner
HealthDay Reporter

TUESDAY, Nov. 18 (HealthDay News) -- In a medical first, a 30-year-old mother of two has successfully undergone the first transplantation of a breathing passage fashioned from a donor's airway and her own stem cells, researchers report.

As of now, the woman, Claudia Castillo, who lives in Barcelona, Spain, with two children aged 15 and 4, does not need immunosuppressive drugs to prevent rejection of the new organ.

She reported that she is able to take care of her two children, can climb two flights of stairs, and even go out dancing some evenings.

"The possibility of avoiding the removal of my entire lung and, instead, replacing only my diseased bronchus with this tissue engineering process represented a unique chance for me to return to a normal life that I am now enjoying with my children and family," Castillo said in a news release.

The doctors who performed the procedure -- from the Hospital Clinic of Barcelona; the University of Bristol, in England; Politecnico di Milano, in Italy, and the University of Padua, in Italy -- reported the feat online Nov. 19 in The Lancet.

"This was a really good opportunity to demonstrate the effectiveness of adult stem cells, which don't have the issues of immunological rejection," said Paul Sanberg, distinguished professor of neurosurgery and director of the University of South Florida Center for Aging and Brain Repair in Tampa. "We clearly need to find ways to really help patients and move into the clinic in these devastating diseases. This demonstrated the utility of bioengineering."

Other experts issued some words of caution.

"Success or failure depends on how much stem cells can take over the function of the donor cells, which have a certain life span. Stem cells have, in theory, a longer life span," said Dr. Len Horovitz, a pulmonary specialist at Lenox Hill Hospital in New York City. "There are more questions in my mind than answers to this, and it's difficult to be able to say, this is definitely the dawn of the future, and this is going to work. We have to see if it's going to work and works in more patients before we can say this is a mainstream approach."

Four years ago, Castillo developed a cough that wouldn't go away; it was eventually diagnosed as tuberculosis. That cough led to a collapsed lung.

By March of this year, Castillo's condition had deteriorated to the point where she was unable to care for her children. Removing a lung was one treatment option, which would have allowed her to live, but seriously impaired her quality of life.

Instead, Castillo received a "new," bioengineered airway.

The scientists essentially created epithelial and cartilage cells from stem cells from Castillo's own bone marrow. Those cells were put on a 7-centimeter piece of trachea from a 51-year-old woman who had died of a brain hemorrhage. Four months later, the scientists had a "hybrid" organ that they used in June to replace Castillo's left main bronchus, which connects the main trachea (windpipe) to the left lung.

The donated organ underwent 25 "washing cycles" to remove donor antigens, which could cause the new tissue to be rejected by the recipient.

Castillo suffered no complications from the surgery and left the hospital 10 days after the procedure.

Tissue bioengineering has already been used to provide organ replacements in other parts of the body, but not in the airway, the study authors said.

"Hopefully the [stem] cells of this woman that were mixed will somehow coat or become integrated [with the donated trachea] so the graft won't be rejected with the assurance that most human tissues are," Horovitz said. "This is the first transplant of this kind. You're using stem cells as an immune modulator, almost to convert the organ from what it was to what you want it to be."

Dr. Ronald Kuppersmith, clinical assistant professor of surgery with the Texas A&M Health Science Center College of Medicine, called the new procedure "exciting" because the "patient didn't have to take immunosuppressant medication."

This approach could eventually have a role in patients who are dealing with weakened immune systems, such as lung cancer patients, he said.