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Gallups, N. J.

Publications and source records attributed to Gallups, N. J..

2 recordsLinked to original sources

IFNγ drives neuroinflammation and demyelination in a mouse model of multiple system atrophy

Multiple system atrophy (MSA) is a rare and fatal synucleinopathy characterized by insoluble alpha-synuclein (-syn) cytoplasmic inclusions located within oligodendroglia. Neuroinflammation, demyelination, and neurodegeneration are correlated with areas of GCI pathology, however it is not known what specifically drives disease pathogenesis. Recently in a mouse model of MSA, CD4+ T cells have been shown to drive neuroinflammation and demyelination, however the mechanism by which this occurs also remains unclear. In this study we use genetic and pharmacological approaches in a novel model of MSA to show that the pro-inflammatory cytokine interferon gamma (IFN{gamma}) drives neuroinflammation and demyelination. Furthermore, using an IFN{gamma} reporter mouse, we found that infiltrating CD4+ T cells were the primary producers of IFN{gamma} in response to -syn overexpression in oligodendrocytes. Results from these studies indicate that IFN{gamma} expression in CD4 T cells drives -syn-mediated neuroinflammation and demyelination, and strategies to target IFN{gamma} expression may be a potential disease modifying therapeutic strategy for MSA.

neuroscience↗

Border-associated macrophages mediate the neuroinflammatory response in an alpha-synuclein model of Parkinson disease

Dopaminergic cell loss due to the accumulation of -syn is a core feature of PD pathogenesis. Neuroinflammation specifically induced by -syn has been shown to exacerbate neurodegeneration, yet the role of CNS resident macrophages in this process remains unclear. We found that a specific subset of CNS resident macrophages, border-associated macrophages (BAMs), play an essential role in mediating -syn related neuroinflammation due to their unique role as the antigen presenting cells necessary to initiate a CD4 T cell response. Surprisingly, the loss of MHCII antigen presentation on microglia had no effect on neuroinflammation. Furthermore, -syn expression led to an expansion in BAM numbers and a unique damage-associated activation state. Through a combinatorial approach of single-cell RNA sequencing and depletion experiments, we found that BAMs played an essential role in immune cell recruitment, infiltration, and antigen presentation. Furthermore, BAMs were identified in post-mortem PD brain in close proximity to T cells. These results point to a critical role for BAMs in mediating PD pathogenesis through their essential role in the orchestration of the -syn-mediated neuroinflammatory response.

neuroscience↗