Gastritis due to Helicobacter pylori is induced by a Th1-mediated response that is CD4 cell and gamma interferon (IFN-gamma) dependent. T-bet is a transcription factor that directs differentiation of and IFN-gamma secretion by CD4+ Th1 T cells. The goal of this study was to use two mouse models to elucidate the role of T-bet in gastritis due to H. pylori. C57BL/6J mice, congenic T-bet knockout (KO) mutants, or congenic SCID (severe, combined immunodeficient) mutants were given live H. pylori by oral inoculation. SCID mice were given CD4+ splenocytes from C57BL/6J or T-bet KO mice by intraperitoneal injection. Twelve or 24 weeks after bacterial inoculation, C57BL/6J mice developed moderate gastritis but T-bet KO mice and SCID mice did not. In contrast, SCID recipients of either C57BL/6J T cells or T-bet KO T cells developed gastritis 4 or 8 weeks after adoptive transfer. In recipients of C57BL/6J CD4+ cells but not recipients of T-bet KO cells, gastritis was associated with a delayed-type hypersensitivity response to H. pylori antigen and elevated gastric and serum IFN-gamma, interleukin 6, and tumor necrosis factor alpha. In spite of the absence of IFN-gamma expression, indicating failure of Th1 differentiation, CD4+ T cells from T-bet KO mice induce gastritis in H. pylori-infected recipient SCID mice. This indicates that Th1-independent mechanisms can cause gastric inflammation and disease due to H. pylori.
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http://dx.doi.org/10.1128/IAI.01887-05 | DOI Listing |
J Immunother Cancer
March 2025
St. John's Institute of Dermatology, School of Basic & Medical Biosciences & KHP Centre for Translational Medicine, King's College London, London, UK
Background: Anti-human epidermal growth factor receptor 2 (HER2) IgG1-based antibody therapies significantly improve cancer prognosis, yet intrinsic or acquired resistance to fragment antigen-binding (Fab)-mediated direct effects commonly occurs. Most resistant tumors retain antigen expression and therefore remain potentially targetable with anti-HER2 therapies that promote immune-mediated responses. Tumor-antigen-specific IgE class antibodies can mediate powerful immune cell-mediated effects against different cancers and have been shown to activate IgE Fc receptor-expressing monocytes.
View Article and Find Full Text PDFGut
March 2025
Department of Gastroenterology, Shanghai Tenth People's Hospital, Shanghai, China
Background: GPR171 suppresses T cell immune responses involved in antitumour immunity, while its role in inflammatory bowel disease (IBD) pathogenesis remains unclear.
Objective: We aimed to investigate the role of GPR171 in modulating CD4 T cell effector functions in IBD and evaluate its therapeutic potential.
Design: We analysed GPR171 expression in colon biopsies and peripheral blood samples from patients with IBD and assessed the impact of GPR171 on CD4 T cell differentiation through administration of its endogenous ligand (BigLEN).
Background: The pathogenesis of female pelvic floor polypropylene mesh complications is unclear as trials evaluating explanted mesh have not included asymptomatic controls.
Objectives: To compare explanted polypropylene mesh from those with and without mesh complications to determine the pathogenesis of the complications.
Methods: Between August 2019 and July 2020 66 participants attending Wesley and Royal Brisbane and Women's Hospital Urogynecology department with mesh complications and 15 undergoing repeat prolapse and/or continence surgery after prior polypropylene mesh implantation were included.
Cell Rep
March 2025
Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC, Canada; Département de médicine, Université de Montréal, Montréal, QC, Canada. Electronic address:
Ansari et al. identified a subset of CD4 T cells (CXCR5PD-1) resembling T follicular helper (Tfh) cells in patients with severe dengue. This subset helps B cell responses via IL-21 and can also differentiate into cytotoxic CD4 T cells.
View Article and Find Full Text PDFCell Rep
March 2025
Vaccine Immunology Laboratory, National Institute of Immunology, New Delhi 110067, India. Electronic address:
Dengue-virus-induced humoral immunity can increase the risk of severe disease, but the factors influencing this response are poorly understood. Here, we investigate the contribution of CD4 T cells to B cell responses in human dengue infection. We identify a dominant peripheral PD-1 T cell subset that accumulates in severe patients and could induce B cell differentiation via interleukin-21 (IL-21)-related pathway.
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