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Yin, C.

Publications and source records attributed to Yin, C..

At least 19 recordsLinked to original sources

Spatial multi-omics reveals novel vascular adipocyte and B cell biology in human abdominal aortic aneurysm

Objective: Perivascular Adipose Tissue (PVAT), tertiary lymphoid structures (TLS), and the B lymphocytes they harbor have been implicated in regulating vascular diseases, including abdominal aortic aneurysm (AAA). Yet, the relationship of adipose tissue to TLS and B cell responses is poorly understood. Approach and Results: Here, we used a multi-omic approach to rigorously define the landscape of human AAA and characterize the adipocyte and TLS microenvironment with regard to B-cell responses to vascular antigens in human AAA and control non-aneurysmal abdominal aortas. Single-nucleus and single-cell RNA sequencing identified transcripts for lipogenesis, lipolysis, extracellular remodeling, haptotactic and chemotactic factors, with potential to recruit CD44+ leukocytes within AAAs. Immunohistology and Visium HD spatial transcriptomics revealed that at least two adipocyte types exist: one in the PVAT and another as isolated clusters in the medial-adventitial region in human AAAs but not in control aortas. Further characterization of these medial-adventitial adipocytes in the AAAs showed close association with TLSs. Mature TLSs recapitulated the organization of functional secondary lymphoid structures, with multiple B-cell follicles clustered to form a nodular structure partly covered by a layer of smooth muscle cells. The TLSs harbored isotype-switched B cells expressing IgG1, IgG3, or IgA, with dominant kappa chain usage and abundant IgG antibodies to aortic wall. Myeloid cells in AAA were implicated in promoting B cell effects, as they were the primary producers of B-cell activating factor (BAFF), a cytokine that promotes B cell infiltration, survival, and function. Conclusion: Altogether, our results support a novel model in which new adipocytes in the medial-adventitial layer produce factors that promote early TLS formation, and BAFF produced by myeloid cells promotes the survival and maturation of vascular wall-antigen-exposed B cells, leading to mature TLS formation, production of antibodies to AAA antigens, fueling inflammation and AAA growth.

immunology↗

Emergence of tunneling nanotube-like intervesicular connections

Tunneling nanotubes (TNTs) are actin-supported membrane bridges that mediate long-range intercellular communication and direct transfer of signaling molecules, organelles, and pathogenic cargo, yet the physicochemical mechanisms underlying their formation and organization remain poorly understood. Here we show that TNT-like intervesicular connections emerge from minimal physicochemical interactions between actin filaments and lipid membranes. Upon Mg2+ exposure, actin-encapsulating vesicles spontaneously generated actin bundle-embedded lipid nanotubes (AT-LNTs) that formed stable intervesicular networks. Mg2+ simultaneously induced actin polymerization, filament bundling, and electrostatic recruitment of F-actin to phosphatidylcholine membranes, enabling membrane tubulation without actin-binding proteins. Systematic perturbation of membrane phase, membrane tension, Mg2+ concentration, ionic strength, and actin concentration revealed that AT-LNT formation occurs only within a narrow physicochemical regime where membrane deformation and actin-membrane coupling are simultaneously permissive. The resulting AT-LNTs reproduced key structural and dynamic features of cellular TNTs, including bundled organization, helical unwinding, lumenal diffusion, and spontaneous bridging between synthetic vesicles and living cells. These findings establish a minimal biophysical framework for understanding the emergence of intercellular membrane connections in living systems and provide a foundation for engineering communication between synthetic and living cell.

synthetic biology↗

RNA m6A demethylase ALKBH4 governs whitefly development

N6-methyladenosine (m6A) modification is the most predominant and ubiquitous internal modification of RNA in eukaryotes, serving as a key post-transcriptional regulator of gene expression that is dynamically modulated by methyltransferases (writers) and demethylases (erasers). However, while the functions of m6A methylases have been partially elucidated in insects, the identity of m6A erasers in arthropods and their chemical catalytic mechanisms, as well as biological functions, remains largely enigmatic. Here, we uncovered 2499 putative methylase genes and 1148 putative demethylase genes in 266 insect genomes, and demonstrated that ALKBH4 functions as an m6A demethylase in the whitefly, Bemisia tabaci, catalyzing the oxidative reversal of mRNA m6A modifications both in vitro and in vivo. Furthermore, we established that ALKBH4, in coordination with other core components of the m6A pathway, fulfills an essential function in regulating the transcript stability of Imaginal Disk Growth Factor 1 (IDGF1) during whitefly development. Collectively, our findings expand the evolutionary scope of the eukaryotic m6A modification system, and reveal a conserved yet insect-specific epitranscriptomic regulatory mechanism governing fundamental physiological processes and adaptive phenotypes. Significance statementThe addition of a methyl group to the N6-position of adenosine (m6A) is a highly abundant chemical modification of RNA. However, the functional role of m6A in insects and the key enzymes that regulate its levels remains poorly understood. In this study, we explored putative methylase genes and demethylase genes in hundreds insect genomes, and identified an m6A RNA demethylase, ALKBH4, in the whitefly, Bemisia tabaci. We demonstrate that ALKBH4 oxidatively reverses mRNA methylation in vivo and in vitro, in combination with other components of the m6A pathway, plays an important role in whitefly development. These findings provide new insight into m6A methylation system of insect.

zoology↗

Anti-Z-NA antibodies can distinguish accessible Z-form states across DNA, RNA, and DNA-RNA substrates

Left-handed (Z-form) double-stranded nucleic acid conformers (Z-DNA and Z-RNA, collectively called Z-NA) are molecular patterns recognized by ADAR1 and ZBP1, which are sensor proteins involved in innate immunity. Monoclonal antibodies raised against Z-DNA, such as Z22 and Z-D11, are employed as probes for the study of Z-NAs, but their substrate specificity and functional equivalence remain unclear. Here, we used biochemical, biophysical, and structural approaches to compare the binding modes and target specificies of Z22 and Z-D11, using Z-prone CG-rich dsDNA, dsRNA, and DNA-RNA hybrids as substrates. Both antibodies failed to form stable complexes with short CG-rich dsRNA under conditions compatible with antibody stability, which suggests that they are unable to induce A-to-Z transitions in dsRNA. In contrast, both antibodies robustly complexed with dsDNA and DNA-RNA hybrid substrates. Cryo-EM structural analysis confirmed that both antibodies interact with Z-NA through a conserved interaction network, and demonstrated that complexes between the antibodies and DNA-RNA hybrids adopted distinct higher-order organizations. Z22 retained binding to both Z-DNA and Z-RNA segments, whereas Z-D11 displayed substrate-dependent organization and was restricted to Z-DNA segments Molecular modelling provided mechanistic explanation for the differences in Z-RNA binding ability between the two antibodies, which was confirmed in situ with ADAR1-depleted, IAV- infected and JTE607-treated cells. We also demonstrate that Z-D11, in contrast to previously described Z22, is unable to induce B-to-Z-transitions in short d(CG)6 oligos under physiological conditions. Together, these results show that anti Z-NA monoclonal antibodies are not functionally interchangeable: whereas Z22 recognizes pre-formed Z-RNA, Z-DNA- RNA hybrids, and Z-DNA, Z-D11 recognizes Z-DNA, and DNA segments in Z-DNA-RNA hybrids. These differences are dictated by substrate composition, local geometry, and conformational accessibility, which also likely impact their ability to induce NA structural transitions. These findings have important implications for interpreting antibody-based detection of left-handed nucleic acids in biological systems.

biophysics↗

High glucose confers senescence resistance via GLUT1 epigenetic rewiring to blunt immunotherapy responses in esophageal squamous cell carcinoma

Therapeutic resistance and undefined predictive biomarkers severely hinder the clinical popularization of immunotherapy in esophageal squamous cell carcinoma (ESCC). Herein, we identify the glucose transporter 1 (GLUT1) as a critical determinant of immunotherapy resistance. Elevated expression of GLUT1 correlates with poor immunotherapy response and unfavorable prognosis in ESCC patients. GLUT1 deletion or inhibition enhances CD8 T cell infiltration and cytotoxicity, and sensitizes ESCC tumors to anti-PD-1 (-PD1) therapy. Importantly, dietary glucose restriction exhibits equivalent antitumor efficacy to GLUT1 inhibition when combined with -PD1. Mechanistically, GLUT1 establishes a positive feedback loop with HAT1 and FOXM1, which epigenetically remodels chromatin accessibility to suppress tumor cell senescence, thereby impeding CD8 T cell-mediated antitumor immunity. Our findings highlight GLUT1 as a predictive biomarker of immunotherapy resistance and suggest dietary glucose restriction as a viable strategy to potentiate immunotherapy efficacy in ESCC. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=188 HEIGHT=200 SRC="FIGDIR/small/738372v1_ufig1.gif" ALT="Figure 1"> View larger version (52K): org.highwire.dtl.DTLVardef@c2c5d5org.highwire.dtl.DTLVardef@14a34c7org.highwire.dtl.DTLVardef@cf05e4org.highwire.dtl.DTLVardef@18bc354_HPS_FORMAT_FIGEXP M_FIG C_FIG SHORT SUMMARYDong et al. identify glucose transporter 1 (GLUT1) as a predictor of poor response to immunotherapy in esophageal squamous cell carcinoma. GLUT1 promotes immune evasion by forming a positive feedback loop with the HAT1/FOXM1 anti-senescence axis, thereby epigenetically remodeling chromatin accessibility. GLUT1 inhibition or dietary glucose restriction restores CD8 T-cell-mediated antitumor immunity and improves the efficacy of anti-PD-1 therapy in preclinical models.

cancer biology↗

A horizontally transferred fungal deubiquitinase facilitates insecticides resistance in whitefly

Horizontal gene transfer (HGT) has enabled insects to acquire novel genetic material that can fuel adaptation to environmental change. However, the role of HGT in the evolution of insecticide resistance remains poorly characterised. Here, we identify BtUCH19, a fungal gene that has integrated into the genome of the global pest Bemisia tabaci and functions as a deubiquitinating enzyme (DUB). We show that compared to endogenous DUB, BtUCH19 specifically removes K63-linked ubiquitin chains from a cytochrome P450, CYP4C64, thereby stabilizing this key detoxification enzyme in vivo. Sustained CYP4C64 abundance enhances metabolic detoxification of two commonly used insecticides thiamethoxam (TMX) and clothianidin (CLO) to their low-toxicity products TMX-Urea and CLO-Urea. Consequently, BtUCH19 drives insecticide resistance through a novel "HGT-PTM-Metab" axis. Our work reveals the instrumental role of a HGT in orchestrating ubiquitin-proteasome system (UPS)-mediated protein level regulation of a key detoxification pathway. These findings offer new insights into the intricate mechanisms underlying co-evolutionary biology, and provide a new molecular target for Integrated Pest Management (IPM).

zoology↗

Quantifying PD1 saturation by PDL1 in tumor tissue using a novel RNA aptamer-based assay

BackgroundTherapeutic agents targeting the PD1-PDL1 interaction are of great clinical value, however accurately predicting which patients are most likely to benefit is challenging. Improved predictive biomarkers for anti-PD1 therapy are clearly needed. Quantifying PD1 saturation by PDL1 in tumor tissue has the potential to serve as such a biomarker. Here we report a novel bioassay called the PD1 Ligand Receptor Complex Aptamer (LIRECAP) assay and demonstrate it can be used to quantify the saturation of PD1 by PDL1 in formalin-fixed paraffin-embedded tumor biospecimens. ResultsThe PD1 LIRECAP assay was developed by identifying a pair of RNA aptamers. One aptamer preferentially binds to unoccupied PD1 (P aptamer) and the other to the PD1-PDL1 complex (C aptamer). P and C aptamers were added together to a formalin-fixed sample, and bound aptamer extracted. A 2-color qRT-PCR assay using a single set of primers was used to determine the ratio of the sample-bound C to P aptamers (C:P ratio) which reflected PD1 saturation by PDL1 in the sample. Quantification of PD1 saturation by PDL1 as determined by the PD1 LIRECAP assay correlated closely with PD1-mediated signaling and PD1-PDL1 proximity. Analysis of sarcoma FFPE biospecimens confirmed the assay is technically reproducible on clinical biospecimens. There were significant differences in PD1 saturation by PDL1 between patients as well as considerable intratumoral heterogeneity. ConclusionsThe PD1 LIRECAP assay is novel assay that can be used to quantify PD1 saturation by PDL1 in clinical biospecimens. The assay is technically feasible, reproducible, and has the potential to serve as a superior predictive biomarker for PD1/PDL1-based therapy. Similar assays based on this platform could be used in other systems and settings to quantify interaction between two molecules.

immunology↗

Ecdysone Receptor autonomously controls germ cell differentiation in the Drosophila ovary

In the Drosophila ovary, the steroid hormone ecdysone controls germline stem cell (GSC) maintenance and germ cell differentiation. Prior studies demonstrated that ecdysone regulates germ cell differentiation non-autonomously via the nuclear receptor Ecdysone Receptor (EcR) in ovarian somatic cells. Although EcR is also expressed in GSCs and their differentiating daughters, potential direct roles for EcR in GSCs independent of the soma have not been examined. Here, we demonstrate that EcR functions autonomously in GSCs and cystoblasts to control germline differentiation. While depletion of EcR from GSCs mildly reduces GSC self-renewal, over-expression of EcR specifically in GSCs and cystoblasts impedes germ cell differentiation, phenotypically resembling bag of marbles loss-of-function and Bone Morphogenetic Protein signaling constitutive activation. We propose that while low levels of EcR are essential to maintain GSC self-renewal and permit initial differentiation, higher levels of EcR accumulate in differentiated germ cells to promote transcription of maternal genes, providing temporal control over germline differentiation. These data support the model that stem cells harbor unique mechanisms to integrate signals from multiple cell sources that safeguard their self-renewal in response to local and physiological cues. SUMMARY STATEMENTThe nuclear receptor EcR modulates stem cell maintenance and differentiation in ovarian germ cells.

developmental biology↗

Cryo-EM structures of anti Z-DNA antibodies in complex with antigen reveal distinct recognition modes of a left-handed geometry

Double-stranded nucleic acids can undergo transitions from canonical B/A-forms to alternate left-handed Z-DNA/Z-RNA (Z-NAs). Z-NAs are implicated in processes such as neuroinflammation in Alzheimers disease, Lupus Erythematosus, microbial biofilms, and type I interferon-mediated human pathologies. Since endogenous Z-NA sensors like the Z domain can induce B-to-Z transitions, monoclonal antibodies (mAbs) Z-D11 and Z22 have been regarded as conformation-specific tools to confirm Z-NA in situ, although high-resolution structural information is missing. Here, we employed single-particle cryo-electron microscopy to solve structures of Z-D11 and Z22 bound to synthetic d(CG)6 12mer Z-DNA duplex. Both mAbs form filamentous trimers around the Z-DNA axis, further stabilized by Fab-Fab interactions. The mAbs achieve specificity through extensive contacts to both Z-form backbone strands and the exposed guanine/cytosine bases in the major groove. This mode of recognition is dictated by shape complementarity rather than sequence specificity, sensing the alternating syn/anti backbone torsions and the phosphate zig-zag geometry unique to Z-DNA. Our data also suggest that these mAbs are not inducing B-to-Z transitions under normal physiological conditions. Finally, comparison to other double-stranded NA-binding mAbs defines a similar structural logic adapted to different helical geometry recognition patterns, thus providing a framework for engineering highly specific nucleic acid probes.

biochemistry↗

Longitudinal Metabolomic Profiling of Biogenic Amines in Plasma and CSF, and Their Correlation, Reveals Sex-Specific and Age Changes in TgF344 Alzheimer's Disease Transgenic and Wildtype Rats

BackgroundAlterations in amine metabolism have been implicated Alzheimers disease (AD). Cerebrospinal fluid (CSF) and plasma are key biofluids in AD research. CSF is considered to better reflect brain metabolic alterations than plasma, while plasma can be obtained more easily. However, plasma-CSF relationships are unclear. AimTo investigate longitudinal changes of amines in plasma and CSF, and their correlation across the two, in male and female TgF344 AD transgenic versus wildtype (WT) rats. MethodLC-MS-based targeted metabolomics was used to analyze 60 and 55 amines in plasma and CSF, respectively, of male and female TgF344-AD and WT rats, at 12, 25, 50 and 85 weeks. Statistical analysis was performed using generalized logistic regressions, Pearson correlations, and differential correlations between groups and matrixes. ResultsCompared to WT controls, at 12 weeks, TgF344-AD rats showed an increase of 3-methylhistidine, anserine, cysteine, s-methylcysteine, while at 25 weeks, male TgF344-AD rats showed pronounced increases in CSF levels of alpha-aminobutyric acid, asparagine, glycylglycine, glycylproline, histidine, isoleucine, kynurenine, leucine, methionine, methionine sulfone, norepinephrine, phenylalanine, proline, tyrosine, and valine. At 50 weeks, female TgF344-AD rats exhibited reductions in CSF for DL-3-aminoisobutyric acid, gamma-aminobutyric acid, ornithine, and putrescine. Distinct plasma-CSF correlations were found for 1-methylhistidine, 2-aminoadipic acid, putrescine, kynurenine, N6,N6,N6-trimethyl-lysine, DL-3-aminoisobutyric acid, and taurine, particularly in TgF344-AD rats. ConclusionsBody fluid, age- and sex-dependent amine alterations in CSF and plasma of TgF344-AD rats compared to WT controls provide important insights into AD disease processes and may aid early diagnosis and therapeutic targeting.

systems biology↗

Altering cell size asymmetry in Drosophila neural stem cells creates supernumerary stem cells with limited lineage expansion potential

Asymmetrically dividing invertebrate and vertebrate stem cells can generate unequal sized sibling cells. However, the functional implications of cell size asymmetry (CSA) are underexplored. Here, we use Drosophila neural stem cells (NSCs) to investigate how changes in CSA impact NSC proliferation and cell fate decisions. Using live cell imaging, NSC lineage analysis, and gene expression profiling, we find that altering CSA increases the NSC pool but decreases lineage size and the number of differentiating progeny cells. Modeling CSA in silico with a volume-sensitivity and NSC self-inhibition model can recapitulate these findings. Gene expression profiling further revealed that the NSC growth regulator Imp and the G1-S cell cycle regulator CycE are upregulated in NSCs with altered CSA, providing a potential molecular link to the volume-sensitivity model. We propose that cell size and position regulate NSC proliferation and differential potential, impacting lineage progression and progeny cell differentiation in the developing Drosophila brain.

cell biology↗

The engulfment receptor Draper is required for epidermal dendrite ensheathment

Our experience of the external world is shaped by somatosensory neurons (SSNs) that innervate our skin and mediate responses to a range of environmental stimuli. The precise innervation patterns and response properties of SSNs are determined in part by specialized interactions with resident skin cells. One such interaction involves the preferential ensheathment of some SSNs by epidermal cells, an evolutionarily conserved intercellular interaction that regulates SSN morphogenesis and mechanical nociceptive sensitivity in Drosophila. The morphogenetic events during ensheathment resemble phagocytic engulfment, therefore we hypothesized that phagocytic receptors mediate molecular recognition of neurites to induce ensheathment. From a screen of epidermally expressed phagocytic receptors we found that the nimrod receptor gene Draper (Drpr) functions in epidermal cells to promote ensheathment. Endogenous Drpr accumulates at sites of epidermal ensheathment but not at epidermal contact sites with unensheathed neurites. Furthermore, overexpressing Drpr increased ensheathment selectively on neurons that are normally ensheathed, suggesting that molecular recognition by Drpr accounts for the specificity of ensheathment. Indeed, we found that an extracellular reporter for the Drpr ligand Phosphatidylserine (PS) accumulates at sites of ensheathment, and that preventing extracellular PS exposure by overexpressing the PS Flippase ATP8a blocked ensheathment. We additionally found that Orion, which encodes a chemokine-like protein that bridges Drpr-PS interactions, is required for sheath formation. Finally, we found that increasing ensheathment by overexpressing Drpr enhanced nociceptor sensitivity to mechanical stimulus. Altogether, these studies show that Drpr acts in epidermal cells to mediate molecular recognition events that drive ensheathment of neurites marked by extracellular PS.

neuroscience↗

Accurate detection and quantification of single-base m6A RNA modification using nanopore signals with multi-view deep learning

N6-methyladenosine (m6A) is a crucial epitranscriptomic mark. While Nanopore Direct RNA Sequencing (DRS) enables transcriptome-wide detection, most existing methods neglect or lack the capacity to effectively process the intrinsically variable-length raw signals generated by DRS reads.Here, we present MultiNano, a multi-view deep learning framework that converts variable-length raw signals into image-like feature representations, effectively resolving the length inconsistency problem. By integrating raw signal and basecalling features, MultiNano enables accurate and comprehensive transcriptome-wide detection of m6A modifications. Our model achieved state-of-the-art (SOTA) performance in various tasks, including site-level prediction, read-level prediction, cross-species transfer learning, and modification rate estimation. Furthermore, the false positive control strategy implemented in MultiNano significantly enhances the models robustness and predictive accuracy, offering a powerful alternative to traditional thresholding-based filtering algorithms. Collectively, our approach provides novel insights for the absolute quantification and single-base resolution of RNA modifications.

bioinformatics↗

A high-quality bread wheat genome unravels adaptive evolution of wheat end-use quality

Understanding the genetics of superior dough performance is essential for improving wheat end-use quality. Here, we presented a de novo assembly of the genome of JM44, a Chinese wheat cultivar known for its exceptional end-use quality. The JM44 genome achieved reference-level quality (QV = 66.74), depicting a complete picture of complex regions containing gluten genes. Our microsynteny analysis across the Triticum-Aegilops complex showed that high-molecular-weight glutenin subunits (HMW-GSs) loci are highly conserved, while low-molecular-weight glutenin subunits (LMW-GSs) and -/{beta}-gliadins exhibited greater structural variation. These variable loci appear to have been preferentially selected by humans and contributed substantially to the evolution of wheat quality traits. Moreover, we observed that epistatic interactions between gluten genes are strong in modern cultivars, but markedly weaker in landraces, indicating the importance of epistatic selection during modern breeding. Our findings shed light on the genomics and evolution of wheat quality traits, providing valuable guidance for future breeding efforts.

genomics↗

Systematic investigation of Epstein-Barr virus transcriptional regulator interactions with the human genome

We systematically investigate interactions between Epstein-Barr virus (EBV) transcriptional regulators (vTRs) and the human genome. Starting with 16 known and candidate vTRs, we identify nine whose introduction into human cells results in substantial alterations to host gene expression. Genome-scale determination of vTR genomic binding events and alterations to chromatin accessibility reveals a detailed map of EBVs functional interactions with the human genome, including >100,000 vTR binding events impacting almost a quarter of all human genes. BMRF1 emerges as a potent regulator, impacting >7,000 genes and altering >37,000 chromatin regions. Our results provide new evidence that EBV RTA interacts with and stabilizes the binding of human RBPJ. Network analysis reveals that many human genes are targeted by multiple EBV vTRs, highlighting the vast coordinated impact of EBV on human gene expression. This study provides a valuable, extensive resource for examining EBV-induced alterations to human gene regulation, with data available on multiple platforms.

genomics↗

Cortical neural landscape captures mouse-to-mouse variability in anticipatory vs. inattentive decision making

Understanding individual variability in behavior is crucial for both basic and clinical neuroscience, yet it remains challenging to study in traditional single laboratory experiments with small sample size. Leveraging standardized behavioral and neural datasets from the International Brain Laboratory, comprising approximately 100 mice trained on a visual decision-making task, we investigated the structure and neural correlates of inter-animal behavioral variability. Using reaction time analysis and a deep learning-based embedding of individual animals, we uncovered large but low-dimensional differences in behavioral traits. Some mice consistently exhibited anticipatory responses, marked by fast reaction times, while others showed slower, more disengaged behavior. These behavioral profiles were consistent across sessions, with female mice tending to show more anticipatory behavior than males. We hypothesized that this behavioral spectrum reflects differences in the depth of underlying cortical states, reflected in the temporal dynamics of neural activity. Supporting this idea, we found that the characteristic timescale of population activity, measured during both inter-trial intervals and passive periods, correlated with an animals anticipatory tendency across cortical areas, especially in medial visual areas. These findings suggest that individual differences in the cortical dynamics may underlie distinct decision-making strategies.

neuroscience↗

Self-Reactive B Cells in Artery Tertiary Lymphoid Organs Encode Pathogenic High Affinity Autoantibody in Atherosclerosis

Artery tertiary lymphoid organs (ATLOs) emerge in atherosclerosis which is a chronic inflammatory artery disease with an autoimmune component. However, whether disease-relevant autoimmune B cells emerge in ATLOs and their impacts remains unknown. To map atherosclerosis-specific humoral autoimmunity and define its roles, we isolated germinal-center (GC) B cells from ATLOs and lymph-nodes, expression-cloned 60 autoantibodies and screened them for arterial wall reactivity. ATLO-derived autoantibodies markedly skewed to atherosclerosis-relevant autoantigens versus those of lymph-nodes. One ATLO GC-derived autoantibody bound to histone 2B (H2B) with high-affinity ([~]25 nM). Moreover, vaccination with H2B or adoptive transfer of its cognate autoantibody markedly accelerated atherosclerosis suggesting that ATLOs fail to delete pathogenic high-affinity self-reactive B cells. In a human cohort, total circulating anti H2B antibody titers positively correlated with aortic and coronary artery calcification. We conclude that ATLOs harbor a dysregulated immune tolerance environment permissive for autoreactive B cells that express pathogenic autoantibodies driving atherosclerosis.

immunology↗

Heat-off responses of epidermal cells sensitize Drosophila larvae to noxious inputs

Perception of external thermal stimuli is critical to animal survival, and although an animals skin is the largest contact surface for thermal inputs, contributions of skin cells to noxious temperature sensing have not been extensively explored. Here, we show that exposure to heat transiently sensitizes Drosophila larvae to subsequent noxious stimuli. This sensitization is induced by prior stimulation of epidermal cells but not nociceptors, suggesting that epidermal cells modulate nociceptor function in response to heat exposure. Indeed, we found that Drosophila epidermal cells are intrinsically thermosensitive, exhibiting robust heat-off responses following warming to noxious temperatures as well as responses to cooling below comfortable temperatures. Further, we found that epidermal heat-off calcium responses involve influx of extracellular calcium and require the store-operated calcium channel Orai and its activator Stim. Finally, epidermal heat-off responses and heat-evoked nociceptive sensitization exhibit similar temperature dependencies, and we found that Stim and Orai are required in epidermal cells for heat-evoked nociceptive sensitization. Hence, epidermal thermosensory responses provide a form of adaptive sensitization to facilitate noxious heat avoidance.

neuroscience↗