neuropil thread

Full Definition

Neuropil threads are pathological tau-immunoreactive fibers found in the brain parenchyma between neurons and glial cells. These structures represent abnormally phosphorylated tau protein accumulating in neuronal processes, particularly dendrites and axons. They are one of the hallmark features of Alzheimer disease and other tauopathies, appearing as thin, thread-like structures that can be visualized with silver stains or tau immunohistochemistry. Their density correlates with disease severity and cognitive impairment.

Usage

Usage note: Often mentioned alongside neurofibrillary tangles in tauopathy reports.

In Context

• "Abundant neuropil threads were evident in the temporal cortex using AT8 immunostaining." — Alzheimer disease autopsy report
• "The density of neuropil threads correlated with the Braak stage assessment." — Tauopathy research study