Primary Sjogren’s syndrome (pSS) is a systemic autoimmune inflammatory disease mainly defined by T cell–dominated destruction of exocrine glands. Currently, CD8+T cells were closely related to the pathogenesis of pSS. However, the single-cell immune profiling of pSS and molecular signatures of pathogenic CD8+T cells have not been well elucidated. Our multiomics investigation identified that both T cell and B cell, especially CD8+T cells, were undergoing significant clonal expansion in pSS patients. TCR clonality analysis revealed that peripheral granzyme (GZM) K+CXCR6+CD8+T cells had higher proportion of shared clones with CD69+CD103-CD8+ tissue resident memory T (TRM) cells in labial glands in pSS. CD69+CD103-CD8+TRM cells featured by high expression of GZMK were more active and cytotoxic in pSS compared with their CD103+ counterparts. Peripheral GZMK+CXCR6+CD8+T cells with higher CD122 expression were increased and harbored a gene signature similar to TRM cells in pSS. Consistently, IL-15 was significantly elevated in pSS plasma and showed the capacity to promote differentiation of CD8+T cells into GZMK+CXCR6+CD8+T cells in a STAT5 dependent manner. Taken together, we depicted the immune landscape of pSS and further conducted comprehensive bioinformatics analysis and in vitro experimental investigation to characterize the pathogenic role and differentiation trajectory of CD8+TRM cells in pSS.
Ting Xu, Hao-Xian Zhu, Xing You, Jin-Fen Ma, Xin Li, Pan-Yue Luo, Yang Li, Zhe-Xiong Lian, Cai-Yue Gao
Low capacity to produce reactive oxygen species (ROS) due to mutations in neutrophil cytosolic factor 1 (NCF1/p47phox), a component of NADPH oxidase 2 (NOX2) complex, is strongly associated with systemic lupus erythematosus in both humans and mouse models. Here, we aim to identify the key immune cell type(s) and cellular mechanisms driving lupus pathogenesis under the condition of NCF1-dependent ROS deficiency. Using a set of cell-specific Cre-deleter, the human NCF1-339 variant knock-in, and transgenic mouse strains, we show that low ROS production in plasmacytoid dendritic cells (pDCs) exacerbates both pristane-induced lupus and a newly established Yaa-related spontaneous model by promoting pDC accumulation in multiple organs during lupus development, accompanied by elevated IFNα levels and expression of IFN-stimulated genes. Mechanistic studies reveal that ROS deficiency enhances pDC generation through the AKT/mTOR pathway and CCR2-mediated migration to tissues, which together with hyperactivation of the redox-sensitive STING/IFNα/JAK1/STAT1 cascade further augments type I IFN responses. More importantly, by suppressing these pathways, restoration of NOX2-derived ROS specifically in pDCs protects against lupus. These discoveries explain the causative effect of dysfunctional NCF1 in lupus and demonstrate the protective role of pDC-derived ROS in disease development driven by NCF1-dependent ROS deficiency.
Huqiao Luo, Vilma Urbonaviciute, Amir Ata Saei, Hezheng Lyu, Massimiliano Gaetani, Ákos Végvári, Yanpeng Li, Roman A. Zubarev, Rikard Holmdahl
The widespread presence of autoantibodies in acute infection with SARS-CoV-2 is increasingly recognized, but the prevalence of autoantibodies in non–SARS-CoV-2 infections and critical illness has not yet been reported. We profiled IgG autoantibodies in 267 patients from 5 independent cohorts with non–SARS-CoV-2 viral, bacterial, and noninfectious critical illness. Serum samples were screened using Luminex arrays that included 58 cytokines and 55 autoantigens, many of which are associated with connective tissue diseases (CTDs). Samples positive for anti-cytokine antibodies were tested for receptor blocking activity using cell-based functional assays. Anti-cytokine antibodies were identified in > 50% of patients across all 5 acutely ill cohorts. In critically ill patients, anti-cytokine antibodies were far more common in infected versus uninfected patients. In cell-based functional assays, 11 of 39 samples positive for select anti-cytokine antibodies displayed receptor blocking activity against surface receptors for Type I IFN, GM-CSF, and IL-6. Autoantibodies against CTD-associated autoantigens were also commonly observed, including newly detected antibodies that emerged in longitudinal samples. These findings demonstrate that anti-cytokine and autoantibodies are common across different viral and nonviral infections and range in severity of illness.
Allan Feng, Emily Y. Yang, Andrew Reese Moore, Shaurya Dhingra, Sarah Esther Chang, Xihui Yin, Ruoxi Pi, Elisabeth K.M. Mack, Sara Völkel, Reinhard Geßner, Margrit Gündisch, Andreas Neubauer, Harald Renz, Sotirios Tsiodras, Paraskevi C. Fragkou, Adijat A. Asuni, Joseph E. Levitt, Jennifer G. Wilson, Michelle Leong, Jennifer H. Lumb, Rong Mao, Kassandra Pinedo, Jonasel Roque, Christopher M. Richards, Mikayla Stabile, Gayathri Swaminathan, Maria L. Salagianni, Vasiliki Triantafyllia, Wilhelm Bertrams, Catherine A. Blish, Jan E. Carette, Jennifer Frankovich, Eric Meffre, Kari Christine Nadeau, Upinder Singh, Taia T. Wang, Eline T. Luning Prak, Susanne Herold, Evangelos Andreakos, Bernd Schmeck, Chrysanthi Skevaki, Angela J. Rogers, Paul J. Utz
Neuromyelitis optica spectrum disorders (NMOSD) are inflammatory autoimmune disorders of the CNS. Immunoglobulin G autoantibodies targeting the aquaporin-4 water channel (AQP4-IgG) are the pathogenic effector of NMOSD. Dysregulated T follicular helper (Tfh) cells have been implicated in the loss of B-cell tolerance in autoimmune diseases. The contribution of Tfh cells to disease activity and the therapeutic potential of targeting these cells in NMOSD remain unclear. Here, we established an autoimmune model of NMOSD by immunizing mice against AQP4 via in vivo electroporation. After AQP4 immunization, mice displayed AQP4 autoantibodies in the blood circulation, blood-brain barrier disruption, and IgG infiltration in the spinal cord parenchyma. Moreover, AQP4 immunization induced motor impairments and NMOSD-like pathologies including astrocytopathy, demyelination, axonal loss, and microglia activation. These were associated with increased splenic Tfh, T helper 1 (Th1) and T helper 17 (Th17) cells, memory B cells and plasma cell. AQP4-deficient mice did not displayed motor impairments and NMOSD-like pathologies after AQP4 immunization. Importantly, abrogating inducible costimulator (ICOS)/inducible costimulator ligand (ICOS-L) signalling using anti-ICOS-L antibody depleted Tfh cells and suppressed the response of Th1 and Th17 cells, memory B cells, and plasma cells in AQP4-immunized mice. These findings were associated with ameliorated motor impairments and spinal cord pathologies. This study suggests a role of Tfh cells in the pathophysiology of NMOSD in a novel mouse model with AQP4 autoimmunity. It also provides an animal model for further investigating the immunological mechanisms underlying AQP4 autoimmunity, and for developing novel therapeutic interventions targeting the autoimmune reactions in NMOSD.
Leung-Wah Yick, Oscar Ka-Fai Ma, Ethel Yin-Ying Chan, Krystal Xiwing Yau, Jason Shing-Cheong Kwan, Koon-Ho Chan
A GWAS of patients with anti-neutrophil cytoplasmic antibodies (ANCA) found an association between proteinase-3 (PR3) ANCA and a single-nucleotide polymorphism (SNP) (rs62132293) upstream of PRTN3, encoding PR3. The variant (G-allele) was shown to be an eQTL in healthy controls, but the clinical impact remains unknown. Longitudinally followed ANCA patients(n=401) and healthy controls(n=130) were genotyped. Gene expression was quantified by RT-qPCR from leukocyte RNA. Plasma PR3 was quantified by ELISA. Kaplan-Meier estimates and log rank test were used for clinical outcomes. Among patients, variant carriers had elevated leukocyte PRTN3 expression compared to non-carriers (C/G vs. C/C and G/G vs. C/C, p=0.012 and p=0.001, respectively, effect size 0.24). Healthy controls had low PRTN3 regardless of genotype. MPO expression did not differ by genotype. PRTN3 (message) correlated with circulating PR3 (r=0.36, p<0.0005) and variant carriers had higher plasma PR3 compared to non-carriers (p=0.041). Among variant carriers, there was a 1.66-fold increased risk of relapse in patients with PR3-ANCA vs MPO-ANCA (HR 1.66, 95% CI 1.08, 2.54). The risk allele marked by rs62132293 is clinically significant as it is associated with increased autoantigen and may, in part, explain increased relapse in PR3-ANCA. Our results underscore the role of autoantigen availability in ANCA vasculitis.
Dhruti P. Chen, Claudia P. Aiello, DeMoris A. McCoy, Taylor Stamey, Jiajin Yang, Susan L. Hogan, Yichun Hu, Vimal K. Derebail, Eveline Y. Wu, J. Charles Jennette, Ronald J. Falk, Dominic J. Ciavatta
CD4+ cytotoxic T lymphocytes (CTLs) were recently implicated in immune-mediated inflammation and fibrosis progression of Graves’ orbitopathy (GO). However, little is known about therapeutic targeting CD4+ CTLs. Herein, we studied the effect of rapamycin, an approved mTORC1 inhibitor, in GO mouse model, in vitro and in refractory GO patients. In the adenovirus-induced model, rapamycin significantly decreased the incidence of orbitopathy. This was accompanied by reduction of CD4+ CTLs, and improvement of inflammation, adipogenesis and fibrosis in orbits. CD4+CTLs from active GO patients showed upregulation of mTOR pathway, while rapamycin decreased their proportions and cytotoxic function. Low-dose rapamycin treatment substantially improved diplopia and clinical activity score in steroid-refractory GO patients. Single-cell RNA sequencing revealed that eye motility improvement was closely related to suppression of inflammation and chemotaxis in CD4+ CTLs. In conclusion, rapamycin is a promising treatment for CD4+ CTL-mediated inflammation and fibrosis in GO.
Meng Zhang, Kelvin K.L. Chong, Zi-yi Chen, Hui Guo, Yu-feng Liu, Yong-yong Kang, Yang-jun Li, Ting-ting Shi, Kenneth Ka Hei Lai, Ming-qian He, Kai Ye, George J. Kahaly, Bing-yin Shi, Yue Wang
Type 1 diabetes (T1D) is an autoimmune disease resulting in pancreatic β-cell destruction. Coxsackievirus B3 (CVB3) infection and melanoma differentiation-associated protein 5 (MDA5)-dependent antiviral responses are linked with T1D development. Mutations within IFIH1, encoding for MDA5, are correlated with T1D susceptibility, but how these mutations contribute to T1D remains unclear. Utilizing non-obese diabetic (NOD) mice lacking Ifih1 expression (KO) or containing an in-frame deletion within the ATPase site of the helicase 1 domain of MDA5 (ΔHel1), we tested the hypothesis that partial or complete loss-of-function mutations in MDA5 would delay T1D by impairing proinflammatory pancreatic macrophage and T cell responses. Spontaneous T1D developed in female NOD and KO mice similarly, but was significantly delayed in ΔHel1 mice that may be partly due to a concomitant increase in myeloid-derived suppressor cells. Interestingly, KO male mice had increased spontaneous T1D compared to NOD mice. While NOD and KO mice developed CVB3-accelerated T1D, ΔHel1 mice were protected partly due to decreased type I interferons, pancreatic-infiltrating TNF+ macrophages, IFN-γ+ CD4+ T cells, and perforin+ CD8+ T cells. Furthermore, ΔHel1 MDA5 protein had reduced ATP hydrolysis compared to wild-type MDA5. Our results suggest dampened MDA5 function delays T1D, yet loss of MDA5 promotes T1D.
Samuel I. Blum, Jared P. Taylor, Jessie M. Barra, Ashley R. Burg, Qiao Shang, Shihong Qiu, Oren Shechter, Aleah R. Hayes, Todd J. Green, Aron M. Geurts, Yi-Guang Chen, Hubert M. Tse
The efficacy of abatacept in patients with early diffuse systemic sclerosis (dcSSc) was analyzed to test the hypothesis that patients in the inflammatory intrinsic gene expression subset would show the most significant clinical improvement. 84 participants with dcSSc were randomized to receive abatacept or placebo for 12 months. RNA-seq was performed on 233 skin paired biopsies at baseline, 3- and 6-months. Improvement was defined as a 5 point or >20% change in modified Rodnan skin score (mRSS) between baseline and 12 months. Samples were assigned to intrinsic gene expression subset (inflammatory, fibroproliferative, or normal-like). In the abatacept arm, change in mRSS was most pronounced for the inflammatory (p<0.001) and normal-like (p=0.03) subsets relative to placebo. Participants on placebo remained in their molecular subset while inflammatory participants treated with abatacept moved toward normal-like. The CD28 costimulation pathway decreased in patients that improved on abatacept (FDR=5.88x10-4) and was specific to the inflammatory subset (FDR=0%). Patients in the inflammatory subset had elevation of the CD28 costimulation pathway at baseline relative to fibroproliferative (p = 0.0026) and normal-like (p=0.0001) participants. There was a correlation between improved ΔmRSS and baseline expression of the CD28 costimulation pathway (R=-0.62, p=0.02). This study provides an example of precision medicine in SSc clinical trials.
Bhaven K. Mehta, Monica E. Espinoza, Jennifer M. Franks, Yiwei Yuan, Yue Wang, Tammara Wood, Johann Gudjonsson, Cathie Spino, David A. Fox, Dinesh Khanna, Michael L. Whitfield
Lupus nephritis is a serious complication of systemic lupus erythematosus, mediated by IgG immune complex (IC) deposition in kidneys, with limited treatment options. Kidney macrophages are critical tissue sentinels that express IgG-binding Fcγ receptors (FcγRs), with previous studies identifying prenatally seeded resident macrophages as major IC responders. Using single-cell transcriptomic and spatial analyses in murine and human lupus nephritis, we sought to understand macrophage heterogeneity and subset-specific contributions in disease. In lupus nephritis, the cell fate trajectories of tissue-resident (TrMac) and monocyte-derived (MoMac) kidney macrophages were perturbed, with disease-associated transcriptional states indicating distinct pathogenic roles for TrMac and MoMac subsets. Lupus nephritis–associated MoMac subsets showed marked induction of FcγR response genes, avidly internalized circulating ICs, and presented IC-opsonized antigen. In contrast, lupus nephritis–associated TrMac subsets demonstrated limited IC uptake, but expressed monocyte chemoattractants, and their depletion attenuated monocyte recruitment to the kidney. TrMacs also produced B cell tissue niche factors, suggesting a role in supporting autoantibody-producing lymphoid aggregates. Extensive similarities were observed with human kidney macrophages, revealing cross-species transcriptional disruption in lupus nephritis. Overall, our study suggests a division of labor in the kidney macrophage response in lupus nephritis, with treatment implications — TrMacs orchestrate leukocyte recruitment while MoMacs take up and present IC antigen.
Nathan Richoz, Zewen K. Tuong, Kevin W. Loudon, Eduardo Patiño-Martínez, John R. Ferdinand, Anaïs Portet, Kathleen R. Bashant, Emeline Thevenon, Francesca Rucci, Thomas Hoyler, Tobias Junt, Mariana J. Kaplan, Richard M. Siegel, Menna R. Clatworthy
Leukocyte Adhesion Deficiency Type-1 (LAD-1) is a rare disease resulting from mutations in the gene encoding for the common β-chain of the ß2 integrin family (CD18). The most prominent clinical symptoms are profound leukocytosis and high susceptibility to infections. At the same time, LAD-1 patients are prone to develop autoimmune diseases, but the molecular and cellular mechanisms that result in coexisting immunodeficiency and autoimmunity are still unresolved. CD4+FOXP3+ regulatory T cells (Treg) are known for their essential role in preventing autoimmunity. To understand the role of Treg in LAD-1 development and manifestation of autoimmunity we generated mice specifically lacking CD18 on Treg (CD18Foxp3), resulting in defective LFA-1 expression. Here we demonstrate a crucial role of LFA-1 on Treg to maintain immune homeostasis by modifying T cell – dendritic cell (DC) interactions and CD4+ T cell activation. Treg-specific CD18 deletion did not impair Treg migration into extra-lymphatic organs but resulted in shorter interactions of Treg with DC. In vivo, CD18Foxp3 mice developed spontaneous hyperplasia in lymphatic organs, and diffuse inflammation of the skin and in multiple internal organs. Thus, LFA-1 on Treg is required for the maintenance of immune homeostasis.
Tanja Klaus, Alicia S. Wilson, Elisabeth Vicari, Eva Hadaschik, Matthias Klein, Sara Salome Helbich, Nadine Kamenjarin, Katrin Hodapp, Jenny Schunke, Maximilian Haist, Florian Butsch, Hans C. Probst, Alexander H. Enk, Karsten Mahnke, Ari Waisman, Monika Bednarczyk, Matthias Bros, Tobias Bopp, Stephan Grabbe
No posts were found with this tag.