Scientists implant regenerated lung tissue in rats

Washington, June 25 : Scientists have successfully implanted engineered lung tissue in rats, raising hopes of regeneration of entire lungs for humans.

Lung disease accounts for around 400,000 deaths each year in the US. Lung tissue is difficult to regenerate because it does not generally repair or regenerate beyond the microscopic level.

Laura Niklason, professor in anaesthesiology and biomedical engineering at Yale University, said: "We succeeded in engineering an implantable lung in our rat model that could efficiently exchange oxygen and carbon dioxide, and could oxygenate haemoglobin in the blood."

"This is an early step in the regeneration of entire lungs for larger animals and, eventually, for humans," added Niklason.

The only current way to replace damaged adult lung tissue is to perform lung transplantation, which is highly susceptible to organ rejection and infection and achieves only 10 percent to 20 percent survival at 10 years.

The Yale team's goal was to see if it was possible to successfully implant tissue-engineered lungs, cultured in vitro (lab), that could serve the lung's primary function of exchanging oxygen and carbon dioxide.

The team found that the mechanical characteristics of the engineered lungs were similar to those of native tissues and when implanted, were capable of participating in gas exchange, said a Yale University release.

The Yale team says this is an important first step, but a great deal more research must be done to see if fully functional lungs can be regenerated in vitro, implanted and sustained.

Their paper appeared in the Thursday issue of Science Express.