It really is now possible to grow and culture human brain tissue in a device that costs bit more than a sit down elsewhere. With a $5 washable and reusable microchip, scientists can observe self-organising brain samples, known as brain organoids, growing in real time under a microscope.
These devices, dubbed a “microfluidic bioreactor”, is a 4-by-6-centimetre chip which includes small wells where the brain organoids grow. Each is filled up with nutrient-rich fluid that is pumped in and out automatically, like the fluids that flush through the mind.
Using this technique, Ikram Khan at the Indian Institute of Technology Madras in Chennai and his colleagues at the Massachusetts Institute of Technology (MIT) have now reported the growth of a brain organoid over seven days. This demonstrates that the mind cells can thrive inside the chip, says Khan.
Culturing brain tissue in a laboratory would theoretically let scientists test how individual patients’ brains might react to different varieties of medications.
Devices for growing brain organoids already exist, but for the reason that dishes are sealed shut in order to avoid contamination from microorganisms in the air, it is impossible to include nutrients like amino acids, vitamins, salts and glucose or to remove the waste made by the cells. As a consequence, the cells usually die in a few days.
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To combat that problem, researchers have previously added tiny tubes to deliver nutrients to the brain tissue. However the opaque design of the devices helps it be impossible to watch what’s happening inside the dish – a substantial problem, particularly if scientists want to know the way the tissue reacts to drugs.
So Khan and his colleagues engineered a new, simpler device that combines an evergrowing platform, tiny tubes, drug-injection channels and a good fluid-warming compartment all onto an individual chip, which may be 3D-printed using the same sort of biocompatible resin used in dental surgery. The bioreactors control the flow of replenishing fluid and waste extraction through tubes in an enclosed incubator while providing full visibility.
To test their system, the researchers placed human brain-differentiated stem cells in the wells and programmed fluid flow through the chip. Utilizing a microscope above the platform, they could watch the mind tissue develop for a complete week – essentially before organoids ran out of space within their tiny wells.
During that time, they saw that the cells multiplied and formed a ventricle-like structure, similar to the cavities observed in real brains, says Chloé Delépine at MIT. The ventricle was surrounded by tissue that appeared similar compared to that of the neocortex, a brain layer accountable for higher-order functions like thinking, reasoning and language comprehension.
Mind organoids have reached such a level of development in a laboratory before, but this marks the first time it has happened in a device which allows such good visibility of the tissue, therefore inexpensively, says Delépine.
“My goal is to see this technology reach persons throughout the world who need access to it for his or her healthcare needs,” says Khan, who has since created a start-up company in India to realise this objective.
Journal reference: Biomicrofluidics , DOI: 10.1063/5.0041027
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