{"title":"Roles of fibroblasts in the pathogenesis of inflammatory bowel diseases (IBDs) and IBD-associated fibrosis.","authors":"Takayoshi Ito, Hisako Kayama","doi":"10.1093/intimm/dxaf015","DOIUrl":"https://doi.org/10.1093/intimm/dxaf015","url":null,"abstract":"<p><p>Ulcerative colitis and Crohn's disease, the principal forms of inflammatory bowel disease (IBD), are chronic relapsing inflammatory disorders of the gastrointestinal tract. The incidence and prevalence of IBD have been increasing worldwide, but their etiology remains largely unknown. Although anti-TNF agents can be highly effective in IBD patients, 10%-40% of patients do not respond to primary anti-TNF therapy. Furthermore, anti-TNF therapy for IBD does not prevent the incidence and progression of fibrosis. A growing body of evidence suggests that IBD pathogenesis is associated with epithelial barrier dysfunction, inappropriate immune responses to luminal microorganisms, and environmental factors as well as host genetics. Recently, a variety of mesenchymal stromal cell populations, including fibroblasts and myofibroblasts, have been characterized in individual tissues under homeostatic and inflammatory conditions. The compositions of fibroblasts and myofibroblasts are altered in the intestinal mucosa of IBD patients, and diverse properties of these cells, such as production of pro-inflammatory cytokines and extracellular matrix components, are remodeled. Several studies have demonstrated that IBD-specific fibroblasts are involved in anti-TNF therapy refractoriness. Therefore, a better understanding of the interaction among fibroblasts, epithelial cells, immune cells, and microbes associated with the maintenance and perturbation of intestinal homeostasis may facilitate the identification of novel therapeutic targets for IBD. This review presents the key findings obtained to date regarding the pathological and homeostatic mechanisms by which functionally distinct fibroblasts and myofibroblasts regulate epithelial barrier integrity, immunity, and tissue regeneration in health and in gastrointestinal disorders.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143663352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of pre-vaccination blood and T-cell phenotypes on antibody responses to COVID-19 mRNA vaccine.","authors":"Yu Hidaka, Norihide Jo, Osamu Kikuchi, Masaru Fukahori, Takeshi Sawada, Yutaka Shimazu, Masaki Yamamoto, Kohei Kometani, Miki Nagao, Takako E Nakajima, Manabu Muto, Satoshi Morita, Yoko Hamazaki","doi":"10.1093/intimm/dxaf013","DOIUrl":"https://doi.org/10.1093/intimm/dxaf013","url":null,"abstract":"<p><p>Despite the high effectiveness of the coronavirus disease (COVID-19) mRNA vaccines, both immunogenicity and reactogenicity show substantial interindividual variability. One key challenge is predicting high and low responders using easily measurable parameters. In this study, we performed multivariate linear regression analysis, which allows adjustment for confounding, to explore independent predictive factors for antibody responses. Using data from 216 healthy vaccinated donors aged 23-81 years, we evaluated baseline characteristics, pre-vaccination blood and T-cell phenotypes, and post-vaccination T-cell responses as variables, with anti-receptor-binding domain (RBD) immunoglobulin G (IgG) titers following two doses of BNT162b2 vaccination as the primary outcome. Consistent with previous reports, higher age, a history of allergic disease, and autoimmune disease were associated with lower peak IgG titers. Additionally, the frequencies of interferon-γ+ spike-specific CD4+ T cells (T-cell response) following the first vaccination strongly correlated with higher IgG responses, while those of pre-existing spike-reactive T cells showed no association with peak IgG titers. Furthermore, we identified lower percentages of naïve CD8+ T cells, lower hemoglobin levels, lower lymphocyte counts, and higher mean corpuscular volume as independent pre-vaccination predictors of lower peak IgG levels. Notably, the frequency of naïve CD8+ T cells showed a positive correlation with the peak IgG levels even in univariate analysis. These findings contribute to the individualized prediction of mRNA vaccine efficacy and may provide insights into the mechanisms underlying individual heterogeneity in immune responses.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143663295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"B10 cells promote pro-resolving macrophage function through direct cell-cell contact and IL-10 secretion in Raw 264.7 cells.","authors":"Takumi Memida, Elaheh Dalir Abdolahinia, Guoqin Cao, Sunniva Ruiz, Shengyuan Huang, Satoru Shindo, Shin Nakamura, Jiang Lin, Toshihisa Kawai, Xiaozhe Han","doi":"10.1093/intimm/dxaf012","DOIUrl":"10.1093/intimm/dxaf012","url":null,"abstract":"<p><p>It is well known that regulatory B cells (Breg), especially IL-10-producing regulatory cells (B10), play an important role in immune regulation during inflammatory and infectious diseases. Although it has been revealed that the immune regulatory function of B10 can be exerted through cognate cell-cell contact with T cells, more research is needed to delineate its impact on other key cellular immune components within the immune microenvironment. In this study, we evaluated the effect of B10 on the phenotypic change of macrophages and their pro-resolving functional activities using various co-culture systems. The roles of cell-cell contact and the IL-10 secretion by B10 on macrophage differentiation and function were determined. Splenocytes-derived B10 cells from wild-type (WT) or IL-10 knockout (KO) mice were co-cultured with RAW 264.7 cells in the presence or absence of trans-well inserts. Macrophage polarization, programmed cell death 1 (PD-1) expression, production of specialized pro-resolving mediators (SPMs), and phagocytic activity were evaluated. The results showed that direct B10-macrophage co-culture enhanced the macrophage polarization towards pro-resolving phenotype and their PD-1 expression, which was diminished when the cultured B10 and macrophages were separated by trans-well inserts, or when B cells from IL-10 KO mice were used for the co-culture. In addition, B10 was found to promote the release of specific SPM (RvD5) and phagocytic activity by macrophages after co-culture. These effects were compromised in trans-well co-culture or co-cultures with IL-10-deficient B cells. Our results suggest that B10 promotes pro-resolving macrophage differentiation and function through direct cell-cell contact and IL-10 secretion.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143582297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The immune memory of innate immune systems.","authors":"Yasuhiro Kato, Atsushi Kumanogoh","doi":"10.1093/intimm/dxae067","DOIUrl":"10.1093/intimm/dxae067","url":null,"abstract":"<p><p>Immune memory has long been considered a function specific to adaptive immune systems; however, adaptive immune memory alone has not fully explained the mechanism by which vaccines exert their protective effects against nontarget pathogens. Recently, trained immunity, in which human monocytes vaccinated with bacillus Calmette-Guérin become highly responsive to pathogens other than Mycobacterium tuberculosis, has been reported. However, a phenomenon called endotoxin tolerance is also known, in which monocyte responsiveness is attenuated after the first lipopolysaccharide stimulation. These phenomena represent an altered innate immune response after the initial exposure to the stimulus, indicating that memories are formed in the innate immune system. In this review, we discuss trained immunity and endotoxin tolerance, known as innate immune memory, and innate immune memory formation by mRNA vaccines, which have been newly used in the coronavirus disease 2019 (COVID-19) pandemic and are considered important vaccine modalities in the future.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":"195-202"},"PeriodicalIF":4.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142716128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mayu Yagita-Sakamaki, Takayoshi Ito, Taiki Sakaguchi, Shuichi Shimma, Bo Li, Daisuke Okuzaki, Daisuke Motooka, Shota Nakamura, Koji Hase, Eiichiro Fukusaki, Akira Kikuchi, Takashi Nagasawa, Atsushi Kumanogoh, Kiyoshi Takeda, Hisako Kayama
{"title":"Intestinal Foxl1+ cell-derived CXCL12 maintains epithelial homeostasis by modulating cellular metabolism.","authors":"Mayu Yagita-Sakamaki, Takayoshi Ito, Taiki Sakaguchi, Shuichi Shimma, Bo Li, Daisuke Okuzaki, Daisuke Motooka, Shota Nakamura, Koji Hase, Eiichiro Fukusaki, Akira Kikuchi, Takashi Nagasawa, Atsushi Kumanogoh, Kiyoshi Takeda, Hisako Kayama","doi":"10.1093/intimm/dxae068","DOIUrl":"10.1093/intimm/dxae068","url":null,"abstract":"<p><p>Several mesenchymal cell populations are known to regulate intestinal stem cell (ISC) self-renewal and differentiation. However, the influences of signaling mediators derived from mesenchymal cells other than ISC niche factors on epithelial homeostasis remain poorly understood. Here, we show that host and microbial metabolites, such as taurine and gamma-aminobutyric acid (GABA), act on PDGFRαhigh Foxl1high sub-epithelial mesenchymal cells to regulate their transcription. In addition, we found that CXC chemokine ligand 12 (CXCL12) produced from Foxl1high sub-epithelial mesenchymal cells induces epithelial cell cycle arrest through modulation of the mevalonate-cholesterol synthesis pathway, which suppresses tumor progression in ApcMin/+ mice. We identified that Foxl1high sub-epithelial cells highly express CXCL12 among colonic mesenchymal cells. Foxl1-cre; Cxcl12f/f mice showed an increased number of Ki67+ colonic epithelial cells. CXCL12-induced Ca2+ mobilization facilitated phosphorylation of AMPK in intestinal epithelial cells, which inhibits the maturation of sterol regulatory element-binding proteins (SREBPs) that are responsible for mevalonate pathway activation. Furthermore, Cxcl12 deficiency in Foxl1-expressing cells promoted tumor development in the small and large intestines of ApcMin/+ mice. Collectively, these results demonstrate that CXCL12 secreted from Foxl1high mesenchymal cells manipulates intestinal epithelial cell metabolism, which links to the prevention of tumor progression in ApcMin/+ mice.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":"235-250"},"PeriodicalIF":4.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142948431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"JunB is required for CD8+ T cell responses to acute infections.","authors":"Shukla Sarkar, Naoyuki Taira, Tsung-Han Hsieh, Hsiao-Chiao Chien, Masato Hirota, Shin-Ichi Koizumi, Daiki Sasaki, Miho Tamai, Yu Seto, Mio Miyagi, Hiroki Ishikawa","doi":"10.1093/intimm/dxae063","DOIUrl":"10.1093/intimm/dxae063","url":null,"abstract":"<p><p>Basic-leucine zipper transcription factor ATF-like (BATF) and interferon regulatory factor 4 (IRF4) are crucial transcription factors for the generation of cytotoxic effector and memory CD8+ T cells. JunB is required for expression of genes controlled by BATF and IRF4 in CD4+ T cell responses, but the role of JunB in CD8+ T cells remains unknown. Here, we demonstrate that JunB is essential for cytotoxic CD8+ T cell responses. JunB expression is transiently induced, depending on the T cell receptor signal strength. JunB deficiency severely impairs the clonal expansion of effector CD8+ T cells in response to acute infection with Listeria monocytogenes. Junb-deficient CD8+ T cells fail to control transcription and chromatin accessibility of a specific set of genes regulated by BATF and IRF4, resulting in impaired cell survival, glycolysis, and cytotoxic CD8+ T cell differentiation. Furthermore, JunB deficiency enhances the expression of co-inhibitory receptors, including programmed cell death 1 (PD-1) and T cell immunoglobulin mucin-3 (TIM3) upon activation of naive CD8+ T cells. These results indicate that JunB, in collaboration with BATF and IRF4, promotes multiple key events in the early stage of cytotoxic CD8+ T cell responses.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":"203-220"},"PeriodicalIF":4.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11884676/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142464488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ro5-4864, a translocator protein ligand, regulates T cell-mediated inflammatory responses in skin.","authors":"Yuka Sendai, Kazuyoshi Takeda, Keisuke Ohta, Susumu Nakae, Kyotaro Koshika, Kei Kitamura, Makoto Higuchi, Tatsuya Ichinohe, Toshifumi Azuma, Ko Okumura, Tatsukuni Ohno","doi":"10.1093/intimm/dxae065","DOIUrl":"10.1093/intimm/dxae065","url":null,"abstract":"<p><p>Translocator protein (TSPO) is a mitochondrial outer membrane protein expressed on a variety of immune cells, including macrophages, dendritic cells, and T cells, in addition to neurons and steroid-producing cells. Previous studies of TSPO ligands have suggested that TSPO is involved in multiple cellular functions, including steroidogenesis, immunomodulation, and cell proliferation. Currently, there are limited reports on the effects of TSPO or TSPO ligands on T cell-mediated immune responses. Here, we investigated the involvement of TSPO/TSPO ligand in T cell responses using a 2,4-dinitro-1-fluorobenzene (DNFB)-induced contact hypersensitivity (CH) model. Treatment with Ro5-4864, a TSPO ligand, during DNFB sensitization reduced the number and activation status of CD4+ and CD8+ T cells in draining lymph nodes and alleviated skin inflammation after DNFB challenge. Adoptive transfer of Ro5-4864-treated mouse-derived DNFB-sensitized T cells to naive mice inhibited CH responses after DNFB challenge. Ro5-4864-treated sensitized T cells showed lower proliferative responses when stimulated with DNFB-pulsed antigen-presenting cells compared to control-treated sensitized T cells. Ro5-4864 also suppressed cell proliferation, as well as adenosine triphosphate and lactate production, during T cell activation. Moreover, the inhibitory effects of Ro5-4864 on T cell responses were conserved in TSPO-deficient cells. Our results suggest that Ro5-4864 inhibits CH responses by suppressing energy metabolism, at least via glycolysis, to reduce the T cell primary response in a TSPO-independent manner.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":"221-234"},"PeriodicalIF":4.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142499829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Keishi Fujio, Toshiyuki Ushijima, Tomohisa Okamura, Mineto Ota
{"title":"The role of polyreactive memory B cells in systemic lupus erythematosus.","authors":"Keishi Fujio, Toshiyuki Ushijima, Tomohisa Okamura, Mineto Ota","doi":"10.1093/intimm/dxae058","DOIUrl":"10.1093/intimm/dxae058","url":null,"abstract":"<p><p>In systemic lupus erythematosus (SLE), the production of autoantibodies is a crucial characteristic, and B cells play a significant role in its pathogenesis. B cells are the immune cells most associated with the genetic predispositions of SLE, and recent clinical studies showing that anti-CD19 chimeric antigen receptor (CAR)-T cell therapy induces drug-free remission have underscored the importance of B cells in SLE. Meanwhile, various B-cell subsets exist across different stages of differentiation, from naive B cells to plasma cells, and identifying the important subpopulations within SLE remains a critical future challenge. Years of B-cell repertoire analyses have revealed the importance of polyreactive B-cell receptors (BCRs) and autoantibodies that react to various self-antigens and microbial antigens. Particularly, memory B cells with polyreactive BCRs, which play a crucial role in biological defense during the fetal stage, are characteristically differentiated in SLE. Type I interferon-mediated expression of CXCL13 and IL-21 in CD4+ T cells is associated with the development of polyreactive memory B cells. The expansion of the polyreactive B-cell repertoire, vital for defending against infections such as viruses, may exert an intrinsic function in SLE.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":"189-194"},"PeriodicalIF":4.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11884719/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142602068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The TET-TDG axis in T cells and biological processes.","authors":"Kazumasa Suzuki, Anjana Rao, Atsushi Onodera","doi":"10.1093/intimm/dxaf006","DOIUrl":"10.1093/intimm/dxaf006","url":null,"abstract":"<p><p>Ten-eleven translocation (TET) proteins are dioxygenases that sequentially oxidize the methyl group of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC). All three epigenetic modifications are intermediates in DNA demethylation. In the \"passive\" (replication-dependent) DNA demethylation pathway, sequential oxidation reactions by TETs are essential and modified cytosines (C) are diluted at each cycle of DNA replication. In the \"active\" (replication-independent) DNA demethylation pathway, both thymine DNA glycosylase (TDG) and TETs play important roles. TDG removes 5fC and 5caC from 5fC:G and 5caC:G base pairs and these modified bases are replaced by unmodified C via base excision repair. Through epigenetic regulation of DNA demethylation, TETs and TDG are involved in cell development, differentiation, and homeostasis. The interplay between TDG and TETs is involved in embryo development, stem cell differentiation, neural development, immune responses, and tumorigenesis. Loss-of-function mutations of TET proteins in immune cells are associated with a variety of abnormalities, including inflammation, cancer, and clonal hematopoiesis, a condition related to aging. Loss of TETs also has a significant impact on the plasticity and differentiation of T cells, which contributes to inflammation and cancer. In this review, we describe recent findings in function of TETs in T cell plasticity and differentiation and the TET-TDG axis in selected biological processes.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143373958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Correlation of Interferons and Autoimmune Aspects in Long COVID-19 Patients.","authors":"Fumiyuki Hattori, Junji Nishiyama, Hideaki Hasuo","doi":"10.1093/intimm/dxaf008","DOIUrl":"https://doi.org/10.1093/intimm/dxaf008","url":null,"abstract":"<p><p>Long COVID, or post-acute sequelae of COVID-19 (PASC), represents a major global health challenge, with its underlying mechanisms remaining poorly understood despite substantial research and clinical trials. This study investigates the role of the interferon (IFN) axis in the pathogenesis of PASC, drawing parallels to systemic lupus erythematosus (SLE). The potential pathogenic role of IFNs was detected by meta-analyses of mRNA sequencing data comparing PASC patients to healthy controls. We analyzed serum samples from 39 PASC patients and found significant correlations among multiple IFN subtypes, including IFN alpha-2, beta, gamma, lambda-1, and lambda-2/3. The biological activity of IFNs in the serum was positively correlated with levels of both total and type III IFNs. Notably, we detected the widespread presence of anti-double-stranded DNA (anti-dsDNA) and anti-Smith (anti-Sm) antibodies in these patients, with anti-dsDNA levels showing a strong correlation with IFN activity. Based on these findings, we propose a hypothetical autoimmune pathogenesis for PASC highlighting the crucial role of IFN signaling.</p>","PeriodicalId":13743,"journal":{"name":"International immunology","volume":" ","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143373956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}