Immune System Linked to Neurological Disease
Cells that help protect the nervous system may also contribute to the development of neurodegenerative disorders like Alzheimer's disease, according to researchers at Case Western Reserve University School of Medicine.
While tau protein is a natural part of a neuron's structure, abnormal accumulations can produce threadlike deposits that damage cells, leading to tauopathies—a family of neurological disorders characterized by abnormal buildup of tau protein, including Alzheimer's and other kinds of dementia.
Previous research has suggested a link between inflammation in the nervous system and tauopathies. Specifically, immune cells called microglia have been implicated in the development of multiple neurodegenerative disorders.
To explore this connection, a research team led by Bruce T. Lamb, PhD, professor with both the School of Medicine and the Cleveland Clinic Lerner College of Medicine of Case Western Reserve and neuroscientist at Cleveland Clinic, studied a specific signaling pathway through which neurons and microglia communicate. The team found that inflammation promoted the accumulation of tau protein in several different models, including biologic models and tests of lab-grown cells.
A key finding, according to Lamb, was that introducing a deficiency of a specific microglial receptor altered the activation of the immune cell, as well as enhanced accumulation of tau protein and behavioral abnormalities in the biologic models.
In addition to documenting the effects of a specific receptor on the accumulation of tau protein, the researchers also gained new insight into signaling molecules. Taken together, the findings reveal a direct link between the activation of microglia and abnormal aggregation of tau in neurons and suggest potential for new therapies.