Emilia Schneider Revueltas, Marta Ferreira-Gomes, Gabriela Maria Guerra, Pawel Durek, Frederik Heinrich, Anna Casanovas Subirana, Koji Tokoyoda, Jun Dong, Simon Reinke, Sebastian Hardt, Christian Hipfl, Thomas Dörner, Carsten Perka, Ute Hoffmann, Hyun-Dong Chang, Mir-Farzin Mashreghi, Andreas Radbruch
{"title":"Surface CD69-Negative CD4 and CD8 Bone Marrow-Resident Human Memory T Cells","authors":"Emilia Schneider Revueltas, Marta Ferreira-Gomes, Gabriela Maria Guerra, Pawel Durek, Frederik Heinrich, Anna Casanovas Subirana, Koji Tokoyoda, Jun Dong, Simon Reinke, Sebastian Hardt, Christian Hipfl, Thomas Dörner, Carsten Perka, Ute Hoffmann, Hyun-Dong Chang, Mir-Farzin Mashreghi, Andreas Radbruch","doi":"10.1002/eji.202451529","DOIUrl":"https://doi.org/10.1002/eji.202451529","url":null,"abstract":"<p>Across tissues, tissue-resident memory T cells have been defined as cells that express CD69 on their cell surface but not sphingosine-1-phosphate receptor 1 (S1PR1), the receptor for the tissue-egress signal sphingosine-1-phosphate (S1P). It is less clear whether CD69-negative memory T cells are also tissue-resident. Here, we compare transcriptomes and T cell receptor repertoires of individual CD4 and CD8 memory T cells from paired blood and bone marrow samples from three human donors. CD69<sup>−</sup> memory T cells of blood and bone marrow share transcriptionally defined clusters, characterized by signature genes and reflecting their imprinting during original activation. However, cells of related clusters from blood and bone marrow have different TCR repertoires, evidence that they represent distinct compartments of memory and indicating that the CD69<sup>−</sup> memory T cells are residents of the bone marrow. Interestingly, the surface CD69<sup>−</sup> memory T cells of bone marrow do transcribe the CD69 gene and express S1PR1, suggesting that they are blindfolded to the perception of the egress signal sphingosine-1-phosphate by dimerization and internalization of CD69 and S1PR1, maintaining them in the bone marrow.</p>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eji.202451529","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144074470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nadia Pulvirenti, Chiara Vasco, Camilla Righetti, Petra Dadova, Giacomo Boffa, Alice Laroni, Tiziana Vigo, Anna Maria Raiola, Maria Cristina Crosti, Stefano Maglie, Luca Valenti, Daniele Prati, Sergio Abrigani, Antonio Uccelli, Jens Geginat
{"title":"The Human Bone Marrow May Offer an IL-15-Dependent Survival Niche for EOMES+ Tr1-Like Cells","authors":"Nadia Pulvirenti, Chiara Vasco, Camilla Righetti, Petra Dadova, Giacomo Boffa, Alice Laroni, Tiziana Vigo, Anna Maria Raiola, Maria Cristina Crosti, Stefano Maglie, Luca Valenti, Daniele Prati, Sergio Abrigani, Antonio Uccelli, Jens Geginat","doi":"10.1002/eji.202451644","DOIUrl":"https://doi.org/10.1002/eji.202451644","url":null,"abstract":"<p>Maintenance of memory T-cells in the bone marrow and systemically depends on the homeostatic cytokines IL-7 and IL-15. An immunological memory may also exist for regulatory T-cells. EOMES<sup>+</sup>type-1 regulatory (Tr1)-like cells have a rapid in vivo turnover, but whether they are short-lived effector cells or are maintained long-term has not been investigated.</p><p>EOMES<sup>+</sup>Tr1-like cells expressing GzmK were enriched among CD69<sup>+</sup>Ki67<sup>−</sup>T-cells in the bone marrow of healthy donors, suggesting that they became quiescent and bone marrow-resident. Conversely, CD4<sup>+</sup>GzmB<sup>+</sup> effector T-cells were excluded from the bone marrow-resident fraction. The dichotomy between GzmK<sup>+</sup> and GzmB<sup>+</sup>T-cells was observed both in healthy individuals and in multiple sclerosis patients, and also among CD8<sup>+</sup>T-cells. Intriguingly, bone marrow-resident CD4<sup>+</sup> memory T-cells expressed increased levels of IL-7Rα, while EOMES<sup>+</sup>Tr1-like cells were consistently IL-7Rα<sup>lo</sup>. However, EOMES<sup>+</sup>Tr1-like cells expressed the IL-2/15Rβ chain, and the latter was induced upon forced expression of EOMES in primary human CD4<sup>+</sup> T-cells. Finally, IL-15 rescued EOMES<sup>+</sup>Tr1-enriched populations from death by neglect but was not required for CD4<sup>+</sup> memory T-cell survival. These findings suggest that the bone marrow may provide a survival niche for EOMES<sup>+</sup>Tr1-like cells. The different IL-7 and IL-15 receptor expression patterns of CD4<sup>+</sup> memory T-cells and EOMES<sup>+</sup>Tr1-like cells suggest furthermore that they compete for different homeostatic niches.</p>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eji.202451644","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144074579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Teresa Steffen, Jesuthas Ajendra, Marianne Koschel, Alexander Palmen, Hannah Wegner, Frederic Risch, Luisa Bach, Manuel Ritter, Marc P. Hübner, Dirk Baumjohann
{"title":"Escalation of Germinal Center Responses in Chronic Litomosoides sigmodontis Filarial Infection","authors":"Teresa Steffen, Jesuthas Ajendra, Marianne Koschel, Alexander Palmen, Hannah Wegner, Frederic Risch, Luisa Bach, Manuel Ritter, Marc P. Hübner, Dirk Baumjohann","doi":"10.1002/eji.202451400","DOIUrl":"https://doi.org/10.1002/eji.202451400","url":null,"abstract":"<p>T follicular helper (T<sub>FH</sub>) cells are the primary CD4<sup>+</sup> T helper cell subset providing help to B cells for efficient antibody responses in vaccination, allergy, autoimmunity, and infectious diseases. Despite their critical involvement in immunity, T<sub>FH</sub> cells’ specific role in filarial infections remains unclear. Using the rodent filarial model <i>Litomosoides sigmodontis</i>, we examined T<sub>FH</sub> and germinal center (GC) B cell responses in lung-draining mediastinal lymph nodes (medLNs) over a 110-day infection period in naive and infected wildtype (WT) BALB/c mice, as well as eosinophil-deficient dblGATA mice, using flow cytometry and ELISA. We observed robust and prolonged T<sub>FH</sub> and GC B cell responses in medLNs of infected BALB/c mice, along with enduring IgG1 antibody responses next to a persistent systemic humoral immune response. We further provide evidence of dysregulated T<sub>FH</sub>/T follicular regulatory (T<sub>FR</sub>) cell ratios in medLNs. Finally, elevated T<sub>FH</sub> cell frequencies in medLNs of dblGATA mice reaffirm the significant role of eosinophils during chronic infection. In conclusion, our findings provide novel insights into population changes of T<sub>FH</sub> and GC B cells during filarial infection.</p>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eji.202451400","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Regulation and Function of the Atypical IκBs—Bcl-3, IκBNS, and IκBζ—in Lymphocytes and Autoimmunity","authors":"Tanja Kübelbeck, Nina Olivera Wichmann, Timsse Raj, Cynthia Raj, Caspar Ohnmacht, Nadine Hövelmeyer, Daniela Kramer, Vigo Heissmeyer","doi":"10.1002/eji.202451273","DOIUrl":"https://doi.org/10.1002/eji.202451273","url":null,"abstract":"<p>Signaling pathways involving NF-κB transcription factors have essential roles in inflammation, immunity, cell proliferation, differentiation, and survival. Classical IκB proteins, such as IκBα and IκBβ, bind to NF-κB via ankyrin repeats to sequester NF-κB in the cytoplasm and thus suppress NF-κB activity. Unlike these constitutively expressed classical IκBs, the expression of the atypical IκBs Bcl-3, IκB<sub>NS</sub>, and IκBζ is induced in immune cells after recognition of antigens, pathogen-associated molecular patterns (PAMPs) or cytokines, upon which they localize to the nucleus and form complexes with transcription factors and regulators on the DNA. Atypical, nuclear IκBs have been proposed to modulate NF-κB activity in a context-dependent manner as they can either inhibit or increase gene expression of a subset of NF-κB target genes. This complexity may be related to the molecular function of atypical IκBs, which bind to different transcription factor complexes and form a bridge to different cofactors or epigenetic modifiers. Recent research has identified novel target genes of atypical IκBs that include chemokines, cytokines, and master regulators of lymphocyte differentiation, underscoring prominent roles in adaptive immune and autoimmune responses. Here, we summarize our current understanding of atypical IκBs in lymphocytes with a focus on their emerging role in autoimmunity.</p>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eji.202451273","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Emelie Backman, Remigius Gröning, Alicia Lind, Christoffer Granvik, Hinnerk Eilers, Anna Lange, Clas Ahlm, Sara Cajander, Mattias N. E. Forsell, Johan Normark, Constantin F. Urban
{"title":"Elevated Plasma Levels of NET Components in Men with Severe COVID-19 Correlates to Increased Amounts of IL-18","authors":"Emelie Backman, Remigius Gröning, Alicia Lind, Christoffer Granvik, Hinnerk Eilers, Anna Lange, Clas Ahlm, Sara Cajander, Mattias N. E. Forsell, Johan Normark, Constantin F. Urban","doi":"10.1002/eji.202451546","DOIUrl":"https://doi.org/10.1002/eji.202451546","url":null,"abstract":"<p>Severe COVID-19 disease is accompanied by high plasma levels of proinflammatory, prothrombotic NETs, and NET-inducing cytokine IL-18. We found that both, IL-18 and NETs, are elevated in men with severe disease, but not in women of the same category. Our findings warrant further investigation of sex-related differences in SARS-CoV-2 infection.\u0000\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eji.202451546","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143930443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Repeated CD107a Staining Enables Identification of Serial Degranulating NK Cells","authors":"Jens Niemann, Maren Claus, Vanna Imširović, Carsten Watzl","doi":"10.1002/eji.202451642","DOIUrl":"https://doi.org/10.1002/eji.202451642","url":null,"abstract":"<p>Upon repeated target cell contact serial degranulating NK cells are identified by multiple staining events using differentially labeled anti-CD107a (LAMP1) antibodies. This flow-cytometry-based method allows for the characterization and isolation of serial degranulating NK cells.\u0000\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eji.202451642","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143930444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Els Lebegge, Daliya Kancheva, Jolien Van Craenenbroeck, Sam Ernst, Pauline M. R. Bardet, Aarushi A. Caro, Máté Kiss, Neema Ahishakiye Jumapili, Romina Mora Barthelmess, Maida Zivalj, Naela Assaf, Leen Ali, Yvon Elkrim, Jesse Demuytere, Jan De Jonge, Geert Raes, Eva Hadadi, Nick Devoogdt, Cécile Vincke, Kiavash Mohavedi, Lars Vereecke, Wim Ceelen, Benoit Stijlemans, Damya Laoui, Sana M. Arnouk, Jo A. Van Ginderachter
{"title":"VSIG4-Expressing Macrophages Contribute to Antiparasitic and Antimetastatic Responses in the Peritoneal Cavity","authors":"Els Lebegge, Daliya Kancheva, Jolien Van Craenenbroeck, Sam Ernst, Pauline M. R. Bardet, Aarushi A. Caro, Máté Kiss, Neema Ahishakiye Jumapili, Romina Mora Barthelmess, Maida Zivalj, Naela Assaf, Leen Ali, Yvon Elkrim, Jesse Demuytere, Jan De Jonge, Geert Raes, Eva Hadadi, Nick Devoogdt, Cécile Vincke, Kiavash Mohavedi, Lars Vereecke, Wim Ceelen, Benoit Stijlemans, Damya Laoui, Sana M. Arnouk, Jo A. Van Ginderachter","doi":"10.1002/eji.202551804","DOIUrl":"https://doi.org/10.1002/eji.202551804","url":null,"abstract":"<p>Large peritoneal macrophages (LPMs) play a role as gatekeepers of peritoneal homeostasis by providing a first line of defense against pathogens. A third of the LPMs express the surface receptor VSIG4, but it is unclear whether these cells differ from their VSIG4-negative counterparts and perform dedicated functions. We demonstrate that VSIG4<sup>+</sup>, but not VSIG4<sup>−</sup>, LPMs are in the majority derived from embryonal precursors, and their occurrence is largely independent of sex and microbiota but increases with age. Although their transcriptome and surface proteome are indistinguishable from VSIG4<sup>−</sup> LPMs at steady-state, VSIG4<sup>+</sup> LPMs are superior in phagocytosing <i>S. aureus</i> bioparticles and colorectal carcinoma (CRC) cells. Anti-VSIG4 nanobody constructs that are ADCC-enabled allowed a selective elimination of the VSIG4<sup>+</sup> LPM subset without affecting overall LPM abundance. This strategy uncovered a role for VSIG4<sup>+</sup> LPMs in lowering the first peak of parasitemia in a <i>Trypanosoma brucei brucei</i> infection model and in reducing CRC outgrowth in the peritoneal cavity, a prime metastatic site in CRC patients. Altogether, our data uncover a protective role for VSIG4<sup>+</sup> LPMs in infectious and oncological diseases in the peritoneal cavity.</p>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eji.202551804","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143930454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fran Prenen, Emilie Pollenus, Hanne Meers, Sofie Knoops, Rebecca Sadler, Margot Deckers, Evanna L. Mills, Philippe E. Van den Steen
{"title":"Itaconate Has Limited Protective Effects in Experimental Malaria Models","authors":"Fran Prenen, Emilie Pollenus, Hanne Meers, Sofie Knoops, Rebecca Sadler, Margot Deckers, Evanna L. Mills, Philippe E. Van den Steen","doi":"10.1002/eji.202451595","DOIUrl":"https://doi.org/10.1002/eji.202451595","url":null,"abstract":"<div>\u0000 \u0000 <p>In severe malaria, dysregulated metabolism and excessive inflammatory responses contribute to fatal outcomes. Therapeutic strategies that address both metabolic and inflammatory balances are thus required. Itaconate, a metabolite produced by aconitate decarboxylase 1 (ACOD1), is a potent inhibitor of both inflammation and glycolysis with protective effects in various inflammatory diseases. Although elevated itaconate levels have been observed in <i>Plasmodium</i>-infected individuals, its role in malaria is still poorly understood, making further investigation essential for assessing its therapeutic potential. We investigated the role of itaconate in both severe and mild malaria using <i>Plasmodium berghei</i> NK65 (<i>Pb</i>NK65) and <i>Plasmodium chabaudi</i> AS (<i>Pc</i>AS) models, respectively. Using <sup>13</sup>C-tracer metabolomics, we detected increased itaconate levels in various organs during infection and identified inflammatory monocytes as the source of this production. Nevertheless, ACOD1 knockout mice displayed no significant changes in phenotype after <i>Pb</i>NK65 infection, and treatment of <i>Pb</i>NK65-infected mice with 4-octyl itaconate did not affect disease severity either. However, in the <i>Pc</i>AS model, ACOD1 deficiency worsened the disease, as indicated by increased weight loss, higher clinical scores, and elevated parasitemia. Therefore, in contrast to the findings in recent literature, our study shows that itaconate does not contribute to susceptibility, but rather provides limited protection to malaria.</p>\u0000 </div>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143930357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Updates on Toll-Like Receptor 10 Research","authors":"Federica Riva, Marta Muzio","doi":"10.1002/eji.202551840","DOIUrl":"https://doi.org/10.1002/eji.202551840","url":null,"abstract":"<p>Toll-like receptors (TLRs) are transmembrane proteins that share sequence similarity and biological function as they are responsible for the innate immune response to exogenous or endogenous molecular patterns. Distinct ligands are recognized by the leucine-rich repeats regions and trigger an inflammatory signal into the cell thanks to the TIR domain of TLR. TLR10 shares the same structural organization but shows a unique expression pattern and functional activity yet to be fully elucidated. In this review, we summarize the literature on TLR10 expression and cellular localization. Several polymorphisms were reported for the TLR10 gene that is present in most mammalians and arose from gene duplication of an ancestral TLR1-like gene. Accordingly, TLR10 was shown to act as TLR1 in terms of TLR2 interaction and TLR1/2 ligands recognition; however, in contrast to all the other TLRs it could also trigger anti-inflammatory signaling and was responsive to several unrelated microbial components. In this review, we will describe key steps and recent updates on TLR10 research highlighting common or divergent findings, in humans and animals.</p>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eji.202551840","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143930356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Treg Control of CD80/CD86 Expression Mediates Immune System Homeostasis","authors":"Yong-Hee Kim, Abir K. Panda, Ethan M. Shevach","doi":"10.1002/eji.202551771","DOIUrl":"https://doi.org/10.1002/eji.202551771","url":null,"abstract":"<p>Foxp3<sup>+</sup> regulatory T cells (Treg) are critical for the maintenance of self-tolerance, and their absence or dysfunction can result in autoimmunity. To determine the critical cell type controlled by Treg and potentially the suppressor mechanism utilized by Treg in the steady state, we utilized mice expressing the diphtheria toxin receptor (DTR) exclusively on Treg cells. Complete depletion of Treg was achieved 24 h after DT treatment, but profound activation of CD4<sup>+</sup> and CD8<sup>+</sup> T cells as measured by induction of CD44 expression and proliferation required 3–4 days. Increased expression of CD80/CD86 was observed on dendritic cells and more prominently on macrophages after 3 days. Depletion of CD4<sup>+</sup> T cells or macrophages resulted in ∼50% inhibition of T-cell activation. The initial steps in T-cell activation were completely independent of IFN-γ or IL-2, while upregulation of CD80/CD86 was partially dependent on IFN-γ. Complete reversal of immune activation post-Treg depletion was only achieved by blockade of CD80/CD86 interactions with CD28. We conclude that the major mechanism used by Treg in the steady state is the regulation of CD80/CD86 expression and dysregulation of this suppressor pathway results in lethal autoimmunity driven by co-stimulatory signals in concert with TCR stimulation, or even by costimulatory signals alone.</p>","PeriodicalId":165,"journal":{"name":"European Journal of Immunology","volume":"55 5","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eji.202551771","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143930453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}