Scientists Make First Step Towards Growing Human Lungs For Transplant

Scientists have successfully converted human embryonic stem cells into lung cells, taking a first step towards building human lungs for transplantation.

According to research to be published in the journal Tissue Engineering, the team from Imperial College London, took human embryonic stem cells and 'directed' them to convert into the type of cells needed for gas exchange in the lung, known as mature small airway epithelium. Dame Professor Julia Polak, from Imperial College London, who led the research team, says: "This is a very exciting development, and could be a huge step towards being able to build human lungs for transplantation or to repair lungs severely damaged by incurable diseases such as cancer." The research involved taking human embryonic stem cells and growing them in Petri dishes in the laboratory in a specialized system that encouraged them to change into the cells that line the part of the lung where oxygen is absorbed and carbon dioxide excreted. Although this was done in the first instance on embryonic stem cells, the system will be tested further on stem cells from other sources, including umbilical cord blood and bone marrow. Dr Anne Bishop, from Imperial College London and based at Chelsea and Westminster Hospital, and senior author of the paper, adds: "Although it will be some years before we are able to build actual human lungs for transplantation, this is a major step towards deriving cells that could be used to repair damaged lungs." Following further laboratory tests, the researchers plan to use their findings to treat problems such as acute respiratory distress syndrome (ARDS), a condition which causes the lining of the cells to fall off, and which currently kills many intensive care patients. By injecting stem cells that will become lung cells, they hope to be able to repopulate the lung lining. (Source: Imperial College London: Tissue Engineering: August 2005.)