Researchers at Karolinska Institutet in Sweden have studied different brain functions during brain development. The study shows how B cells communicate with one another during brain development. The findings could open up opportunities for new approaches to treat brain disorders.

The brain is best understood through the development of cortical connections a process called cortical wiring. Individuals are exposed to various sensory stimuli during that process. Neural connections are then established between the brain regions with two major types of neurons: linear neurons that are active in a set of them and are responsible for long-range communication and median neurons that are active in one of those. However it is not possible to separate mice from humans at this stage because such neurons are highly aberrant in the mouse brain.

Das says they have now succeeded in separating genetically-mimicked neuronal cultures from both mice and humans. They have studied the communication between B cells and cytotoxic T lymphocytes (endothelial lymphocytes) in this way which is important for the development of this neural network. We have shown that these behaviors are actually regulated by the level of the host immune system. It is the B cells that promote the development of more expensive cognitive functions in video-driven mice and the traffic of the intermediate cells that yield the long-range communication says Dr. Dahlin. This suggests that the communication is indirectly regulated by the behavior of these good neighbours until the mouse is old enough to distinguish them.

Distinguishing B cells and adults.

The scientists then looked at adult animals and showed how B cells differentiate into their larger forms – great for communication between brain regions. We were able to show that B cells send signals to those aged and abnormal and that these signals are regulated by their agonistic receptors says Dr. Dahlin.

Sexing occurs in the beginning of a mouses life but by the time the animal attained present age much has occurred. Most of the genes still reside unchanged in the animal as they do in humans. The hypothalamus for example. In the mid-twenty late teens the Treg cells are programmed to mature and to give out a hand-off signal to neighbouring B cells. This would allow a healthy adult to differentiate into a B cell. As a result signals can be picked up by the host and processed but the determination of differences in the B cell types arrives at separate stages in the mouse brain explains Dr. Dahlin.

The mechanisms are not completely clear yet. Therefore the researchers do not yet know if the tortuous communication is regulated by the endothelial cells of the nervous system. The muscles could possibly be involved in this process. We know that some nerve cells in the muscles become pore-filling and do this in turn to facilitate blood clotting and arousal. These are the kinds of mechanisms that we could study in more depth explains Dr. Dahlin.