bioRxiv Science⌕ Search

bioRxiv · 10.1101/2024.05.28.596190

Oligodendrocyte precursor cells exacerbate acute CNS inflammation via macrophage and T cell activation in a mouse model of multiple sclerosis

Abstract

Oligodendrocyte precursor cells (OPCs) are a type of glial cell that differentiates into mature oligodendrocytes, a cell type that contributes to myelination, but their roles in the pathologies are not fully understood. Activities other than differentiation into oligodendrocytes have recently been reported for OPCs present in the inflammatory milieu, but intervention studies using animal models are lacking. This study aimed to explore the role of OPCs in mouse MS model experimental autoimmune encephalomyelitis (EAE). Using inducible diphtheria toxin receptor-expressing transgenic mice, platelet-derived growth factor receptor A (PDGFR)+ OPCs were depleted in EAE mice. Surprisingly, OPC depletion in the acute phase improved clinical scores and reduced demyelination. Major histocompatibility complex (MHC) class II was reduced in the spinal cord, whereas astrocyte marker and blood-spinal cord barrier tight junction and adhesion molecule expressions were unaffected after OPC depletion. The numbers of T cells and IL17-expressing Th17 cells were decreased in the spinal cords of the OPC-depleted group. MHC class II expression in spinal cord macrophages was consistently decreased by OPC depletion. These data suggest that in the acute phase of EAE, OPCs are involved in activation of infiltrated macrophages and induce subsequent T cell activation and neuroinflammation. Although the precise mechanisms remain unclear, this implies that OPCs exist not only as the source for oligodendrocytes but also play a pivotal role in central nervous system (CNS) autoimmune inflammation. Table of Contents Image O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=72 SRC="FIGDIR/small/596190v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@98162dorg.highwire.dtl.DTLVardef@d7f92dorg.highwire.dtl.DTLVardef@1280619org.highwire.dtl.DTLVardef@a85907_HPS_FORMAT_FIGEXP M_FIG C_FIG MAIN POINTSO_LIOPC depletion in the acute phase of EAE improved clinical scores and reduced demyelination. C_LIO_LIOPC depletion in the spinal cord suppressed Antigen presentation via MHC class II. C_LIO_LIOPCs are involved in activation of infiltrated macrophages and induce subsequent T cell activation and neuroinflammation. C_LI

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Ohashi, K., Uemura, N., Nagayasu, K., Kaneko, S., Maki, T., Shirakawa, H.. 2024-06-01. Oligodendrocyte precursor cells exacerbate acute CNS inflammation via macrophage and T cell activation in a mouse model of multiple sclerosis. https://doi.org/10.1101/2024.05.28.596190

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

The Unreasonable Effectiveness of Cell Types in Describing Neuronal Physiological Features

Single-cell RNA sequencing (scRNA-seq) captures detailed gene expression profiles at scale, while patch-clamp recordings measure intrinsic neuronal electrophysiological properties. Modeling the relations between these two modalities remains a challenge. Here, we compare how well electrophysiological features can be predicted by traditional transcriptomic cell type classification, representations derived from a foundational model (scGPT) pretrained on large-scale scRNA-seq datasets, ion channel-coding genes, and highly variable genes. Using paired transcriptomic and electrophysiological patch-sequencing data from 495 human neurons from neurosurgical tissue, we find that cluster-level cell type representations consistently outperform highly variable gene selection, ion channel gene selection, and context-enriched scGPT embeddings. Notably, performance varies across model architectures and initializations, and the best results are obtained by combining the outputs of separate cell type and scGPT-based models. Together, these findings suggest that traditional discrete cellular classification is highly effective in predicting physiological features. For maximum performance it can be complemented by pretrained transformer models.

neuroscience↗

A nonlinear inhibition pathway underlying cortical responses to tuned holographic optogenetic perturbations

Optogenetics enables causal manipulation of cortical activity. Perturbation responses can be counterintuitive due to network interactions, making theory essential for predicting them. Existing approaches often rely on linear approximations, which fail for many biologically relevant perturbations. Here we develop a nonlinear theory of responses to holographic perturbations in cell-type-specific recurrent networks with structured connectivity. We fit a nonlinear model to mouse V1 data, which shows cotuned-ensemble suppression: perturbing spatially clustered neurons with similar preferred orientations yields markedly stronger short-range suppression than perturbing untuned ensembles. We show that cotuned-ensemble suppression arises from a feature-tuned, nonlinear inhibition pathway implicating somatostatin-positive (SST) interneurons. The theory predicts that cotuned ensembles suppress parvalbumin-positive (PV) neurons but facilitate SST neurons, and links the degree of cotuned-ensemble suppression or facilitation to the variance of the SST response. This framework identifies mechanisms by which nonlinear inhibition sculpts cortical dynamics and establishes a predictive basis for targeted optogenetic interventions.

neuroscience↗

Proteomic signatures of APOE ε4 across human tissues and cell types in Alzheimers disease

The apolipoprotein E {varepsilon}4 (APOE {varepsilon}4) allele is the strongest genetic risk factor for late-onset Alzheimers disease (AD). However, the underlying molecular mechanisms remain unclear. This study included 1691 participants from the Religious Orders Study and Rush Memory and Aging Project (ROSMAP), 1226 participants from the Accelerating Medicines Partnership - Alzheimers Disease (AMP-AD) Diverse Cohorts Study, and 735 participants from the Alzheimers Disease Neuroimaging Initiative (ADNI). To characterise APOE {varepsilon}4 molecular effects, we analysed proteomic data from plasma, cerebrospinal fluid (CSF), and induced pluripotent stem cell (iPSC)-derived astrocytes and neurons, as well as transcriptomic and proteomic data from multiple brain regions. The association of APOE {varepsilon}4 with AD neuropathology was also examined. APOE {varepsilon}4 carriers shared a plasma proteomic signature enriched for immune processes, irrespective of AD diagnosis. A machine learning classifier trained on this signature discriminated APOE {varepsilon}4 carriers from non-carriers in an independent cohort using CSF proteomics. APOE {varepsilon}4 carriage was associated with higher Braak stages and Consortium to Establish a Registry for Alzheimers Disease (CERAD) score. However, only limited APOE {varepsilon}4-associated transcriptomic and proteomic changes were observed in bulk brain tissue, with poor cross-layer concordance. Proteomic analyses of iPSC-derived astrocytes and neurons further revealed cell-type-specific APOE {varepsilon}4-associated changes. APOE {varepsilon}4 is associated with a consistent proteomic signature across plasma and CSF. Its molecular effects in the brain differ across cell types, brain regions and molecular layers. These findings support the need for cell-type-resolved multi-omic studies to elucidate how APOE {varepsilon}4 confers AD risk.

neuroscience↗