Meningeal T cells function in the central nervous system homeostasis and neurodegenerative diseases

Abstract

Recently, a rising interest is given to neuroimmune communication in physiological and neuropathological conditions. Meningeal immunity is a complex immune environment housing different types of immune cells. Here, we focus on meningeal T cells, possibly the most explored aspect of neuro-immune cell interactions. Emerging data have shown that meningeal T cells play a crucial role in the pathogenesis of several neurodegenerative disorders, including multiple sclerosis, Alzheimer’s, Parkinson’s, and Huntington’s diseases. This review highlights how meningeal T cells may contribute to immune surveillance of the central nervous system (CNS) and regulate neurobehavioral functions through the secretion of cytokines. Overall, this review assesses the recent knowledge of meningeal T cells and their effects on CNS functioning in both health and disease conditions and the underlying mechanisms.

Tissue resident memory CD8+ T cells are present but not critical for demyelination and neurodegeneration in a mouse model of multiple system atrophy

“…In human MSA post-mortem tissue, we have previously reported an increase in CD8+ T cells within the putamen and substantia nigra[ 40 ]. Literature has also shown that CD8+ T cells are retained in dura and leptomeningeal spaces, and upon a stimulus in the brain, will infiltrate into the parenchyma and execute effector functions[ 1 ]. Our results potentially suggest a similar trafficking of CD8+ T cells into the brain that has been described in other studies as α-syn overexpression results in enhanced parenchymal CD8+ T cells but decreased dural CD8+ T cells ( Figure 1B and C ).…”

Promising Strategies to Reduce the SARS-CoV-2 Amyloid Deposition in the Brain and Prevent COVID-19-Exacerbated Dementia and Alzheimer’s Disease

“…Recent studies have demonstrated an important role of MLVs in the protection of the brain against pathogens and the development of neurodegenerative diseases [ 114 , 115 , 116 , 117 ]. Dysfunction of MLVs aggravates Aβ accumulation in the brain and significantly reduces the efficacy of immunotherapy against AD and brain tumors [ 43 , 44 , 118 , 119 ].…”

Interplay between the Glymphatic System and the Endocannabinoid System: Implications for Brain Health and Disease

“…This immune response activates immune cells, including macrophages and microglia, which discharge pro-inflammatory cytokines, chemokines, and other agents fostering inflammation and detriment to myelin and nerve cells. This inflammatory cascade can give rise to demyelinated plaques and axonal loss, the elongated projections of nerve cells accountable for transmitting electrical impulses [66,67].…”

“…Subsequently, the CNS endeavors to effect repair and remyelination, albeit often incomplete, potentially resulting in the formation of scar tissue (gliosis). The recurring cycles of inflammation, demyelination, and repair attempts contribute to the distinctive relapsing-remitting MS pattern, wherein symptoms exacerbate during relapses and partially alleviate during remissions [67].…”