The human gastric pathogen Helicobacter pylori spontaneously switches lipopolysaccharide (LPS) Lewis (Le) antigens on and off (phase-variable expression), but the biological significance of this is unclear. Here, we report that Le+ H. pylori variants are able to bind to the C-type lectin DC-SIGN and present on gastric dendritic cells (DCs), and demonstrate that this interaction blocks T helper cell (Th)1 development. In contrast, Le- variants escape binding to DCs and induce a strong Th1 cell response. In addition, in gastric biopsies challenged ex vivo with Le+ variants that bind DC-SIGN, interleukin 6 production is decreased, indicative of increased immune suppression. Our data indicate a role for LPS phase variation and Le antigen expression by H. pylori in suppressing immune responses through DC-SIGN.
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http://dx.doi.org/10.1084/jem.20041061 | DOI Listing |
Drugs Aging
January 2025
Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
IgG4-related disease (IgG4-RD) is an immune-mediated disorder characterized by organ enlargement and dysfunction. The formation of tertiary lymphoid tissues (TLTs) in affected organs is crucial for understanding IgG4-RD, as T follicular helper (Tfh) 2 cells within TLTs drive IgG4+B cell differentiation, contributing to mass formation. Key cytokines IL-4 and IL-10, produced by Tfh2 cells, are essential for this process.
View Article and Find Full Text PDFInflammation
January 2025
Department of Otorhinolaryngology, Dankook University College of Medicine, 201 Manghyang-Ro, Dongnam-Gu, Cheonan, 31116, Republic of Korea.
During nasal polyp (NP) development, activated T cells differentiate into T helper (Th) 1, Th2, and Th17 cells. Additionally, regulatory T cells (Tregs) that have an immune suppressive function are involved in the pathophysiology of chronic rhinosinusitis (CRS) with NP (CRSwNP). Tregs can act as effector cells that produce inflammatory cytokines, such as interleukin (IL)-17A.
View Article and Find Full Text PDFRheumatology (Oxford)
January 2025
Department of Rheumatology, Hospital Universitario La Paz-IdiPaz, Madrid, Spain.
Objectives: Giant cell arteritis (GCA) is a large/medium-vessel granulomatous vasculitis, and the PD-1/PD-L1 coinhibitory pathway seems to be implicated in its pathogenesis. CD4 T cells expressing high PD-1 levels, CD4+CXCR5-PD-1hi peripheral helper (Tph) and CD4+CXCR5+PD-1hi follicular helper T cells (Tfh), are key mediators of autoimmunity. Their frequencies are elevated in the peripheral blood of subjects with several autoimmune conditions but have not been investigated in GCA.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
University of Melbourne, Parkville, VIC, Australia.
Background: Mounting evidence support the involvement of adaptive immune system in the pathogenesis of Alzheimer's disease (AD). The current study investigated the age-dependent changes in the abundance of B and T cell subtypes in APP/PS1 mice, a commonly used model for AD.
Method: Peripheral blood was collected through cardiac puncture from 6-, 9-, 12-month-old APP/PS1 transgenic (TG) mice (APPsw and PSEN1dE9, n = 8-12) and their wildtype (WT) littermates (C57BL/6J, n = 12-15).
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
December 2024
Department of Toxicology, School of Public Health, Shenyang Medical College, Shenyang 110034, China. *Corresponding author, E-mail:
Objective To investigate the protective effect of curcumin (Cur) against arsenic-induced neuroimmune toxicity and the underlying molecular mechanisms in vivo. Methods Eighty SPF female C57BL/6 mice were randomly assigned to four groups: a control group, an arsenic-treated group, a Cur-treated group and an arsenic+Cur group, with 20 mice in each group. The control group received distilled water; the arsenic-treated group was given 50 mg/L NaAsO in the drinking water; the Cur-treated group was gavaged with 200 mg/kg of curcumin for 45 days; and the arsenic+Cur group received distilled water and was gavaged with 200 mg/kg of curcumin.
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