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Sloan, N.

Publications and source records attributed to Sloan, N..

3 recordsLinked to original sources

Multiscale harmonization and semantic integration of biomedical data enable biological insights through immersive exploration

Single-cell atlassing efforts like the Human BioMolecular Atlas Program (HuBMAP) and the Cellular Senescence Network (SenNet) are producing multiscale datasets across the healthy, adult, human body, but this data is typically explored only on 2D screens with limited 3D affordances, even though understanding a cells location within a tissue, organ, and body requires reasoning across many orders of spatial magnitude. The Human Reference Atlas (HRA) provides standard terminologies and a Common Coordinate Framework (CCF) for harmonizing such data spatially and semantically. Building on the HRA Organ Gallery in virtual reality (VR) application, we present "HRA: Powers of Ten," which integrates, harmonizes, and visualizes biological data from these efforts immersively in VR using a Multiscale Elevator System that lets users descend, like riding an elevator through an inverted skyscraper, from a whole body view of 81 reference organs to datasets across 5 organs (lymph node, brain, large intestine, small intestine, liver), 5 assay types (CODEX, Visium, v-CyCIF, Xenium, SBF-SEM), and 4 spatial scales. Contributed by Data Providers, these VR scenes enable biological insights into senescence patterns, cellular neighborhoods, 3D tissue reconstruction, and subcellular liver architecture. A standard operating procedure supports adding further datasets. Freely available on the Meta Store to over 20 million headset owners, the application, data, and code are open-source.

bioinformatics↗

Uncovering the Signatures of Cellular Senescence in the Human Dorsolateral Prefrontal Cortex

Identifying senescent cells poses challenges due to their rarity, heterogeneity, and lack of a definitive marker. We performed Visium spatial transcriptomics (ST) and single nucleus RNA sequencing (snRNA-seq) on non-pathological human tissue to build a transcriptomic atlas of aging and senescence in the dorsolateral prefrontal cortex (dlPFC). We identified markers characteristic of aging dlPFC cortical layers and cell types. We also observed an increase in astrocyte abundance and decrease in somatostatin expressing inhibitory neurons. Overall, the senescence profile in the dlPFC was highly heterogeneous and heavily influenced by cell type identity and cortical layer. Combined unbiased analysis of ST and snRNA-seq datasets revealed gene expression modules encoding for communities of microglia and endothelial cells in the white matter and regional astrocytes programs that were strongly enriched with age and for senescence-related genes. These findings will help facilitate future studies exploring the function of senescent cell subpopulations in the aging brain.

cell biology↗

Interaction of an α-synuclein epitope with HLA-DRB1*15:01 initiates early enteric features of Parkinson's disease in humanized mice

Enteric symptoms, including constipation, are hallmarks of prodromal Parkinsons disease (PD) that can appear decades before the onset of motor symptoms and diagnosis. PD patients possess circulating T cells that recognize specific -synuclein-(-syn)-derived epitopes. One epitope, -syn32-46, binds with strong affinity to the HLA-DRB1*15:01 allele implicated in autoimmune diseases. We report that -syn32-46 immunization in a mouse expressing HLA-DRB1*15:01 triggers intestinal inflammation leading to loss of enteric neurons, damage of enteric dopaminergic neurons, constipation and weight loss. -Syn32-46 immunization activates innate and adaptive immune gene signatures in the gut and induces changes in CD4+ TH1/ TH17 transcriptome that resemble tissue resident memory cells found in mucosal barriers during inflammation. Depletion of CD4+, but not CD8+, T cells partially rescues enteric neurodegeneration. Therefore, interaction of -syn32-46 and HLA-DRB1*15:0 is critical for gut inflammation and CD4+ T cell-mediated loss of enteric neurons in humanized mice, suggesting potential mechanisms of prodromal enteric PD. HIGHLIGHTS AND eTOC BlurbO_LI-syn32-46 immunization of an HLA-DRB1*15:01 mouse triggers weight loss and constipation. C_LIO_LI-syn32-46 immunizations induce gut inflammation, loss of enteric neurons and damage to dopaminergic neurons. C_LIO_LI-syn32-46 immunization induces innate and adaptive immune responses in the gut. C_LIO_LIDepletion of CD4+, but not CD8+, T cells partially rescues enteric neural loss. C_LIO_LIAn interaction between -syn32-46 and HLA-DRB1*15:01 is critical for this model of prodromal PD. C_LI Parkinsons disease (PD) patients exhibit elevated number of circulating T cells that recognize -synuclein-(-syn)- epitopes, particularly during early disease stages. One epitope, -syn32-46, interacts with the HLA-DRB1*15:01; however, its role in PD pathogenesis remains unknown. Garretti et al. show that -syn32-46 immunization of a mouse expressing HLA-DRB1*15:01 triggers intestinal inflammation, a loss of enteric neurons, constipation and weight loss, suggesting a critical role for -syn autoimmunity in HLA-DRB1*15:01 carriers in prodromal PD.

neuroscience↗