On the side of the University of Cincitatti, the approach is similar. The team of the Faculty of Medicine sought to grow, in the same organoid, cells which form the surface of the organs – called epithelial cells – and the cells of the blood vessels. Usually these two cell types require contrary signals to develop properly, which complicates their co-culture. The researchers therefore developed a very precise cocktail of molecules which allows the two families of cells to grow simultaneously, without one preventing the other from forming. Result: they obtained lung and intestine organoids which contained both the famous epithelial cells and blood vessels.
Organic supergrule
On the brain side, the challenge was even larger. And for good reason: most brain organoids do not reproduce the whole brain, but only a region like the cortex. The researchers therefore cultivated separately neural cells from different brain regions and rudimentary blood vessels before assembling them using adhesive proteins, a sort of “organic supergrule”, allowing tissues to connect. As they gathered, these fabrics began to produce an electrical activity and react in a network.
A feat, of course, but which does not mean that we can now cultivate real human brains in the laboratory. And for good reason: organoids manufactured by Johns Hopkins University – among the most perfected to date – have only between 6 and 7 million neurons, compared to 100 billion for adult human brains. “” These structures partially imitate the function of an organ, but to speak of real organs would be prematureconfirms the biologist Pierre Savatier in the last issue of Futurthe magazine ofUsbek & Ricawithin the framework of an article on the creation of organs to organs. It must be kept in mind that an organ is an extremely complex entity, composed of a heterogeneous mixture of cells, which it is difficult to reproduce. »
To read in the summer issue 2025 of our magazine:
“Bodyoids”, the track of three American researchers to create organs to organs
It is for this reason that most scientists reject the term “mini-organization”. “” Qualify the organoids of [la sorte] Give false hopes to patients, who may believe that replacement organs are already cultivated in the laboratoryadvances a dozen scientists in a forum published in 2023 on the world site. They are still far from reproducing in vitro the function of whole organs and being able to restore it in the human body ».
Regenerative medicine
Although we cannot yet use organoids for transplants, these miniature models are very precious in research. In the space of 10 years, brain organoids have been used to study neurological development disorders, intestinal organoids to model celiac disease, and pulmonary organoids to study SARS-COV-2, the virus originating from COVID-19.