The scientists for the first time created 3D brain models with the use of cells from multiple people.

The researchers have made these new hybrid creations, which are called "chimeroids". These tiny 3D models are variations of brain organoids which are made of tissue which are structured like a full-size brain and function in the same way.

These models are more accurate to human biology in comparison to 2D cellular models or animals such as lab mice. With the help of these models, scientists think that they can accelerate drug research and development. 

Generally, brain organoids are grown from cells which are collected from only one donor. Such brain organoids don't capture the genetic variability which exists between people and have the potential to impact the brain development of individuals and their responses to drugs. 

According to the scientists, who have carried out the new study, the creation of chimeroids will help overcome this hurdle. Such a "village in a dish" can especially be helpful in the early stages of drug testing, they stated. 

Earlier, researchers have grown sheets of brain cells from the stem cells of various people, but this is the first time that the brain's 3D models have been grown this way. 

"Chimeroids are an exciting tool that will be widely adopted in the field of neurodevelopment, probably with diverse applications," said Aparna Bhaduri, who is an assistant professor of biological chemistry at the University of California, Los Angeles, while commenting on the study.

How the chimeroids were grown by scientists?

The stem cells of five people were collected by the researchers to make the chimeroids and then growth-inducing chemicals were used in the lab to push the growth of brain organoids, each of which contained cells from just one person.

The resulting organoids were then torn by the scientists and recombined their cells to form chimeroids. With this, every chimeroid had an equal number of cells taken from each person. 

"I'm excited about what the future holds in terms of using organoids, such as the chimeroids, to develop brand new ways to achieve therapeutic innovation for neurological disease," said Paola Arlotta, co-senior study author and a professor of stem cell and regenerative biology at Harvard University, while speaking to Live Science.