For the first time, American scientists have used stem cells to cultivate lung organoids with a complete vascular network. These 'mini' lungs have a highly similar developmental process to human lungs. This latest achievement, published in the journal Cell, not only reveals the mysteries of early human development, but also lays the foundation for constructing models of other vascularized organs such as the intestine and colon, and provides powerful tools for disease research, drug testing, and personalized treatment. This study was conducted in collaboration between the University of California, Los Angeles and Cincinnati Children's Hospital Medical Center. The research team innovatively adopted a strategy of synchronously cultivating lung tissue and blood vessels, resulting in four major advantages of the obtained organoids: richer cell types, more complete three-dimensional structures, higher cell survival rates, and closer to mature developmental states. The research team was the first to apply this groundbreaking model to the study of pulmonary vein misalignment associated with alveolar capillary dysplasia. This congenital lung disease caused by FOXF1 gene mutation has always been difficult to simulate in traditional organoid models due to its main damage to blood vessels and supporting cells. With the help of a new method, the research team extracted stem cells from FOXF1 mutant patients and grew vascularized lung organoids, successfully reproducing primary vascular defects and the secondary lung tissue abnormalities caused by them. The research team stated that these lung like organs can also be used to study other pulmonary vascular diseases, marking a crucial step for humans in using real human tissue models to study diseases and potentially significantly reducing the dependence of new drug development on animal models. Given that the currently cultivated organoids are only equivalent to the level of fetal lung development, the research team plans to simulate mechanical stretching and air contact during respiration to promote the formation of more mature lung structures in organoids. (New Society)