Lung transplants are among the most complicated medical procedures, and patients have one of the poorest prognosis post-transplant. This is because it’s very difficult to find biocompatible lungs for transplant. Growing new lungs in the lab directly from patients’ cells, however, offers a massive workaround. More or less, the resulting lung would be very similar to the one the patient loses during transplant, greatly reducing the chance the immune system will reject the lung. Growing organs may seem like SciFi and although we’re still far away from seeing a fully fledged, lab-grown organ becoming successfully transplanted, we’re getting there.
“Now, we are finally able to make lung and airway cells,” study leader Dr. Hans-Willem Snoeck, a professor of microbiology and immunology at Columbia University in New York, said in a statement.
A breath of fresh air
Previously, Snoeck and team discovered a set of chemical factors that can turn human embryonic stem (ES) cells or human induced pluripotent stem (iPS) cells (adult skin cells that have been reprogrammed into stem cells) into anterior foregut endoderm – precursors of lung and airway cells. Now, the same researchers have found a set of chemicals that coax stem cells in growing into epithelial cells which coat the surface of lungs.
In fact, resultant cells were found to express markers of at least six types of lung and airway epithelial cells, particularly markers of type 2 alveolar epithelial cells. The kind of cells are vital because they produce surfactant, a substance critical to maintain the lung alveoli, where gas exchange takes place; they also participate in repair of the lung after injury and damage.
“Now, we are finally able to make lung and airway cells. This is important because lung transplants have a particularly poor prognosis. Although any clinical application is still many years away, we can begin thinking about making autologous lung transplants — that is, transplants that use a patient’s own skin cells to generate functional lung tissue,” said the authors of the paper published in the journal Nature Biotechnology.
Transplants may be long away, but lab-grown lungs from diseased patients could serve a much more immediate purpose in the future. Early-stage precursor lungs could become highly valuable in research, where they could act as biological test beds for various types of drugs or kinds of treatment. This applies for virtually any kind of organ. Even in this primitive stage, testing could be made. For instance, idiopathic pulmonary fibrosis (IPF) is a lung disease in which type 2 alveolar epithelial cells are thought to play a central role.
“No one knows what causes the disease, and there’s no way to treat it,” says Dr. Snoeck. “Using this technology, researchers will finally be able to create laboratory models of IPF, study the disease at the molecular level, and screen drugs for possible treatments or cures.”
“In the longer term, we hope to use this technology to make an autologous lung graft,” Dr. Snoeck said. “This would entail taking a lung from a donor; removing all the lung cells, leaving only the lung scaffold; and seeding the scaffold with new lung cells derived from the patient. In this way, rejection problems could be avoided.” Dr. Snoeck is investigating this approach in collaboration with researchers in the Columbia University Department of Biomedical Engineering.
“I am excited about this collaboration with Hans Snoeck, integrating stem cell science with bioengineering in the search for new treatments for lung disease,” said Gordana Vunjak-Novakovic, PhD, co-author of the paper and Mikati Foundation Professor of Biomedical Engineering at Columbia’s Engineering School and professor of medical sciences at Columbia University College of Physicians and Surgeons.