Immune Cell Offers Possible Path To Treating Brain Diseases

The team discovered the new type of granulocyte white blood cell while studying mouse models. This cell is similar to a neutrophil but it secretes growth factors that can help axons of the central nervous system to regenerate according to the team, who suggest to have also identified a subset of human immune cells with similar properties. 

According to Benjamin Segal, M.D., professor and chair of neurology at Ohio State College of Medicine and co-director of the Wexner Medical Center's Neurological Institute the ability of the subset to stimulate the regrowth of severed nerve fibers is “really unprecedented” and "In the future, this line of research might ultimately lead to the development of novel cell-based therapies that restore lost neurological functions across a range of conditions."

Findings published in the journal Nature Immunology describe how the team observed the newly discovered granulocytes being similar to immature neutrophils and the testing for therapeutic power by injecting them into mice with injured optic nerves or broken nerve fibers; findings showed that animals receiving injections regrew nerve fibers while those injected with mature neutrophils did not. 

There is therefore a “dire need” for novel therapies that might not only reduce, but potentially even reverse chronic neurological deficits. “One potential strategy that has been proposed to promote neuroprotection and regeneration involves modulation of the local immune response to CNS damage,” they noted.

The next steps involve collecting the neuro-enhancing granulocytes for additional testing to determine how to enhance them in a lab, to investigate whether these cells could be injected into patients to possibly reverse the damage to the central nervous system. If they are successful this immunotherapy could be beneficial for treating diseases such as ALS and MS as well as for treating traumatic injuries to the brain and spine according to the team. 

“The distinctive mechanism of action of the Ly6Glo neuro-regenerative neutrophil subset makes it an attractive candidate for multimodal therapy, in synergy with agents that block cell-intrinsic or cell-extrinsic suppressors of axon growth, to rescue dying neurons and enhance axonal regeneration after CNS injury,” the team stated. “Our findings could ultimately lead to the development of novel immunotherapies that reverse central nervous damage and restore lost neurological function across a spectrum of diseases.”

Immunotherapy solutions to brain diseases are becoming popular in neurological research. In 2019 researchers from Stanford University described a subpopulation of CD8 T cells that could be boosted to relieve MS symptoms in mice with a peptide. Mount Sinai’s Icahn School of medicine recently reported microglia immune cells tamping down excessive neuron activity. Additionally, the startup Tranquis Therapeutic just launched this summer with $30 million in capital with the goal to target microglia in neurodegenerative diseases.