The researchers made a detailed description of how to change the structure and function of microglial cells and their predecessors in the human brain before birth, reported in Science. It was found that the properties characteristic of immune cells, they acquire between the ninth and eighteenth weeks of fetal development. This is probably one of the reasons why the Central nervous system of the fetus is particularly sensitive to adverse influences during this period.
Microglia is one of the types of immune cells in the brain. They not only fight infection (because the brain is surrounded by blood-brain barrier, most of the pathogens just it misses), but also performs several other functions. For example, in adult mice microglia dispose of the bodies of neurons and their short processes, while the processing of long distant from the cell bodies engaged in processes of astrocytes. During intrauterine development microglia one of the first hits to the brain: detected there even before the formation of the blood-brain barrier, myelin sheaths and maturation of neurons, and it affects all these processes.
By the microglial cells also need to Mature. When ripe, changing the activity of a number of genes that can be tracked using epigenetic markers and transcriptomic (defining the repertoire and quantity of different RNA molecules in cells). Knowwhen and how this happens in mice, but the changes microglial cells during intrauterine development of man is less well known, and large-scale systematic analysis of all processes is still not there.
It was led by neuroscientists from the Netherlands and Belgium under the leadership of Bart Eggen (Bart Eggen) of the University medical center Groningen. They used samples of microglia 23 human fetuses and obtained the transcriptome of single cells for 15782 elements 781 and microglial cells of the nervous system relates to other types.