SCIENCE &TECH

Scientists use stem cells to successfully grow human lungs in a dish A team of researchers from University of California, Los Angeles (UCLA) created a three-dimensional lung, called as organoids, to study diseases, including idiopathic pulmonary fibrosis. The organoids resemble sections of human lungs instead of just cells. The study was published in the journal Stem Cells Translational Medicine. How the researchers grew lungs? • The researchers used stem cells taken from actual adult human lungs to coat tiny sticky hydrogel beads. • The beads eventually grew and self-assembled to envelope the hydrogel beads, which were all placed inside linked wells. • The resulting structure produced evenly distributed three-dimensional patterns consistent with actual air sacs like those in human lungs. • Inside each well, the lung cells grew around the beads, which linked them and formed an evenly distributed three-dimensional pattern. • To show that these tiny organoids mimicked the structure of actual lungs, the researchers compared the lab-grown tissues with real sections of human lung. • Moreover, when the researchers added certain molecular factors to the 3D cultures, the lungs developed scars similar to those seen in the lungs of people who have idiopathic pulmonary fibrosis. • The scientists were not able build a fully functional lung. However, they have been able to take lung cells and place them in the correct geometrical spacing and pattern to mimic a human lung. What is Idiopathic pulmonary fibrosis? • Idiopathic pulmonary fibrosis is a chronic lung disease characterised by scarring of the lungs. • The scarring makes the lungs thick and stiff, which over time results in progressively worsening shortness of breath and lack of oxygen to the brain and vital organs. • The term 'idiopathic' is used because the cause of pulmonary fibrosis is still unknown. • To study the effect of genetic mutations or drugs on lung cells, researchers have previously relied on two-dimensional cultures of the cells. But when they take cells from people with idiopathic pulmonary fibrosis and grow them on these flat cultures, the cells appear healthy.