Human brain immune cells take years to mature, study finds
Human brain immune cells known as microglia can take four to eight years to mature, a process that lasts only about three weeks in mice and may contribute to humans’ advanced cognitive abilities, reports a Qazinform News Agency correspondent.
Researchers at Columbia University’s Zuckerman Institute found that human microglia, much like neurons, develop significantly more slowly than comparable cells in other animals.
“This slow development may help human microglia influence the human brain in ways that enable our powerful cognitive abilities,” said study lead author Carlos Diaz-Salazar.
Microglia are the most abundant immune cells in the brain. Besides protecting it from harmful agents and removing damaged neurons, they play an important role in brain development by helping determine which connections, or synapses, between neurons are maintained or eliminated.
The study, published in Neuron, identified a possible genetic explanation for their unusually slow development. Researchers found that human-specific copies of the SRGAP2 gene were nearly 10 times more abundant in microglia than in neurons.
Experiments involving mice and human cells showed that these copies significantly slowed microglial maturation.
“This gene helps control the developmental tempo of neurons, and nature has also selected it to control the development of microglia that are so crucial to neuron development, so they are in sync during development,” Diaz-Salazar said.
Researcher Franck Polleux said the findings could also improve understanding of brain diseases, as microglia have been linked to neurodevelopmental and neurodegenerative disorders.
“We want to understand all the elements that help make up the human brain to understand what makes us unique from an evolutionary standpoint,” Polleux said.
Earlier, Qazinform News Agency reported that HKU researchers discovered ultrathin diamond membranes can generate electricity when mechanically deformed.