Scientists have, for the first time, grown 3D mini lungs from human stem cells.
The advantage of growing 3D structures is that their organization bears greater similarity to the human lung, and the University of Michigan researchers scientists succeeded in growing structures resembling both the large proximal airways and the small distal airways.
The Ingredients included: Embryonic stem cells, Proteins involved in lung development, Growth factors, Inhibitors of intestine development, Growing media, Petri dish, Protein mixture, Method for 'morphogenesis in a dish.'
First, add protein ActivinA to stem cells and leave for 4 days. Add Noggin, another protein, and a transforming growth factor, and leave for another 4 days. You will find the endoderm is induced to form 3D spherical structures called the foregut spheroids.
Transfer spheroids to protein mixture and incubate at room temperature for 10 minutes until the mixture solidifies. Treat with additional proteins every 4 days and transfer into a new protein mixture every 10-15 days.
The resulting lung organoids should survive in culture for over 100 days and develop into well-organised structures containing cell types found in the lung. You will find the lung organoids are self-organizing, and do not require further manipulation to generate 3-dimensional tissues.
Since these structures were developed in a dish, they lack several components of the native lung, including blood vessels, which are a critical component of gas exchange.
The study is published in eLife.
