When scientists attempt to model human brain diseases using other model organisms, the question always remains whether they can actually identify the cellular roots of these diseases in humans. This new collection of 21 research studies combining science, scientific advances, and scientific translational medicine represents an invaluable resource
to better understand and treat neurological and brain diseases.
These studies were conducted as part of the National Institutes of Health’s BRAIN Initiative Cell Census Network (BICCN) program launched in 2017. The program involved hundreds of scientists collaborating, resulting in a range of studies particularly focused on the most advanced molecular biology technologies.
“These techniques have so far been used mainly in preclinical studies with experimental animal models, but the work presented here shows how human research could go beyond this preclinical work,” summarizes Mattia Maroso, editor-in-chief of the journal Science.
The main work involved in creating the atlas is described in three studies This therefore enabled this first draft of the human brain cell map, including the underlying gene expression and gene regulation architecture. One such study examined the variation in brain cell types in 75 adults undergoing surgery for epilepsy or brain tumors: This research shows how brain cells differ from one patient to another and provides insights. First reference base for cell typing in neurological or brain diseases.
“There is not a single human prototype”some researchers in the project specify: “A wide range of differences in genetic variation and response to the environment can be observed in both healthy people and disease states.”
“There is no cerebral uniformity”: Another study further examines how variation in cell types depends on brain region.
What features of brain cell organization are specific to humans? Another study using transcriptomics shows that chimpanzee neurons are more similar to gorilla neurons than human neurons, even though chimpanzees and humans share a more recent common ancestor. The complex arrangement of cells in our brain is established in our first days of life: Other studies show that cellular states in the human brain are established in the first trimester of life.
Which function is specific to humans? The work explores how fast interneurons in humans enable fast synchronization rates despite larger neuron-to-neuron distances compared to other animal models.
Which universal trigger of neurological disorders? Other studies confirm the “universal” role of inflammation as a trigger for these diseases. And while the effects of inflammation on human brain development are still poorly understood, early studies suggest that they are associated with changes primarily in certain subtypes of inhibitory neurons.
“These valuable data represent a step toward answering fundamental scientific questions about the human brain: the era of cell research on the human brain is just around the corner,” the researchers conclude.