Biology subjects

Webster, J. M.

Publications and source records attributed to Webster, J. M..

6 recordsLinked to original sources

bioRxiv2026

Stage-Specific NF-κB RelA and IRF4 Programs Drive -Synuclein-Induced Disease-Associated Microglia Differentiation

Microglial activation in response to aggregated -synuclein (-syn) accumulation is a pathological hallmark of Parkinson disease (PD). A distinct activated microglial state, disease-associated microglia (DAM), has been identified across multiple neurodegenerative disorders, including PD. However, the transcriptional and epigenetic programs governing DAM differentiation remain unclear. Here, we show that neuronal -syn overexpression drives progressive microglial state transitions toward DAM, accompanied by increased phagocytic activity and enhanced cytokine and chemokine production. Integrative transcriptomic and chromatin accessibility analyses reveal a hierarchical NF-{kappa}B--AP-1--IRF regulatory program underlying these state transitions. Microglial NF-{kappa}B p65 (RelA) or IRF4 deficiency impairs microglial progression toward DAM, with RelA and IRF4 governing early microglial activation and subsequent DAM differentiation, respectively. Enrichment of NF-{kappa}B, AP-1, and IRF motifs in DAM in human PD supports conservation of this regulatory program across species. Together, our findings establish RelA and IRF4 as sequential, stage-specific regulators that coordinate -syn-induced DAM differentiation in PD.

immunology↗

bioRxiv2026

Digital Atlases to Unlock the Potential of Brain Biorepository Tissues for Interdisciplinary Research

Human brain tissue preserved in biorepositories is foundational for the structural, cellular, and biomolecular research necessary for a mechanistic understanding of neurological diseases. Realizing the research potential of these valuable resources requires well-characterized research-relevant tissue that can be efficiently identified by investigators and incorporated into the conceptual and computational frameworks of interdisciplinary research. Several large-scale efforts to improve research reliability and reproducibility have sought to characterize and annotate the processes by which these samples are collected, yet limited progress has been made on standardizing spatial information for these samples. Biorepositories systematically collect brain tissue according to a brain sampling protocol (BSP) that differs between institutions, yet explicit spatial information regarding the samples may not be documented in standard operating procedures (SOPs). The amount of anatomical location details available to investigators are inconsistent across biorepositories and typically lack sufficient anatomical precision to ensure correspondence with samples from other biorepositories or research relevant brain regions specified by neuroimaging, functional, or disease-susceptibility criteria. Here, we introduce a pipeline for developing a Spatial Atlas for Mapping Protocol Locations of Ex vivo Samples (SAMPLES), which uses a neuroimaging framework to create a 3D representation of a BSP through a metrically precise digital instantiation of the procedures for brain extraction, segmentation, slicing, and sampling on a modern digital brain template. SAMPLES incorporates modern neuroinformatics conventions to create explicit 3D labels of BSP-defined samples that can be interactively visualized with freely available neuroimaging software. We illustrate the pipeline by developing an atlas for the protocol from the University of Washington BioRepository and Integrated Neuropathology laboratory (UW BRaIN SAMPLES). By providing an explicit, computable reference, SAMPLES atlases can support the efficient identification, referencing, and utilization of postmortem samples for interdisciplinary research. These capabilities enable biorepository workflows, data harmonization across biorepositories, and integration with antemortem neuroimaging.

neuroscience↗

bioRxiv2024

Amyloid-beta, alpha-synuclein and tau aggregated co-pathologies enhance neuropathology and neuroinflammation

Alzheimers (AD) and Parkinson disease (PD) pathology often co-occur. Amyloid-{beta} and phosphorylated tau are found in 30-50% of idiopathic PD cases, while -synuclein inclusions are present in 50% of AD cases. These co-pathologies are linked to increased mortality and earlier onset of cognitive decline. Immune activation is a hallmark of these neurodegenerative diseases, but current models primarily examine each pathology in isolation. How these co-pathologies drive inflammation and neuronal loss remains poorly understood. We therefore developed a mouse model combining tau, amyloid-{beta}, and -synuclein. We found that co-pathologies synergistically trigger an amplified neuroimmune response, with expanded populations of CD4+ and CD8+ tissue-resident memory T cells and CD68+ microglia, compared to single pathologies. These changes were abundant in the hippocampus and cortex, regions with elevated protein pathology load and enhanced neuronal loss. Our findings demonstrate that co-pathologies enhance proteinopathy and synergistically enhance immune activation and neurodegeneration, suggesting that combinatorial therapeutic strategies that target both co-pathologies and inflammation, may be disease modifying. SummaryWebster et al. demonstrate that co-occurring Alzheimers and Parkinson disease protein pathologies, common in cognitively impaired patient populations, amplify proteinopathy and synergistically enhance CNS neuroinflammatory responses and neurodegeneration. This work supports the need for combinatorial therapeutic strategies and positions neuroinflammation as an important link for co-pathology enhanced neurodegeneration.

neuroscience↗

bioRxiv2024

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

Multiple system atrophy (MSA) is rare, fast progressing, and fatal synucleinopathy with alpha-synuclein (-syn) inclusions located within oligodendroglia called glial cytoplasmic inclusions (GCI). Along with GCI pathology there is severe demyelination, neurodegeneration, and neuroinflammation. In post-mortem tissue, there is significant infiltration of CD8+ T cells into the brain parenchyma, however their role in disease progression is unknown. To determine the role of CD8+ T cells, a modified AAV, Olig001-SYN, was used to selectively overexpress -syn in oligodendrocytes modeling MSA in mice. Four weeks post transduction, we observed significant CD8+ T cell infiltration into the striatum of Olig001-SYN transduced mice recapitulating the CD8+ T cell infiltration observed in post-mortem tissue. To understand the role of CD8+ T cells, a CD8 knockout mice were transduced with Olig001-SYN. Six months post transduction into a mouse lacking CD8+ T cells, demyelination and neurodegeneration were unchanged. Four weeks post transduction, neuroinflammation and demyelination were enhanced in CD8 knockout mice compared to wild type controls. Applying unbiased spectral flow cytometry, CD103+, CD69+, CD44+, CXCR6+, CD8+ T cells were identified when -syn was present in oligodendrocytes, suggesting the presence of tissue resident memory CD8+ T (Trm) cells during MSA disease progression. This study indicates that CD8+ T cells are not critical in driving MSA pathology but are needed to modulate the neuroinflammation and demyelination response.

neuroscience↗

bioRxiv2022

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↗

bioRxiv2018

Persistent Underrepresentation of Women’s Science in High Profile Journals

Yiqin Alicia Shen, Jason M. Webster, Yuichi Shoda, and Ione Fine Department of Psychology, University of Washington Past research has demonstrated an under-representation of female editors and reviewers in top scientific journals, but less is known about the representation of women authors within original research articles. We collected research article publication records from 15 high-profile multidisciplinary and neuroscience journals for 2005-2017 and analyzed the representation of women over time, as well as its relationship with journal impact factor. We find that women authors have been persistently underrepresented in high-profile journals. This under-representation has persisted over more than a decade, with glacial improvement over time. Even within our limited group of high profile journals, the percent of female first and last authors is negatively associated with journal impact factor. Since publishing in high-profile journals is a gateway to academic success, this underrepresentation of women may contribute to the lack of women at the top of the academic ladder.

scientific communication and education↗