98%
921
2 minutes
20
Innate-like splenic marginal zone (MZ) B (MZB) cells play unique roles in immunity due to their rapid responsiveness to blood-borne microbes. How MZB cells integrate cell-extrinsic and -intrinsic processes to achieve accelerated responsiveness is unclear. We found that Delta-like1 (Dll1) Notch ligands in splenic fibroblasts regulated MZB cell pool size, migration, and function. Dll1 could not be replaced by the alternative Notch ligand Dll4. Dll1-Notch2 signaling regulated a Myc-dependent gene expression program fostering cell growth and a Myc-independent program controlling cell-movement regulators such as sphingosine-1 phosphate receptor 1 (S1PR1). S1pr1-deficient B cells experienced Notch signaling within B cell follicles without entering the MZ and were retained in the spleen upon Notch deprivation. Key elements of the mouse B cell Notch regulome were preserved in subsets of human memory B cells and B cell lymphomas. Thus, specialized niches program the poised state and patrolling behavior of MZB cells via conserved Myc-dependent and Myc-independent Notch2-regulated mechanisms.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11735314 | PMC |
http://dx.doi.org/10.1016/j.immuni.2024.12.003 | DOI Listing |
Scand J Immunol
September 2025
Department of Molecular Biosciences, the Wenner-Gren Institute, Stockholm University, Stockholm, Sweden.
The initial aim of this study on Balb/C mice was to investigate the putative effects on feeding and appetite of isopentenyl pyrophosphate (IPP) and E-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), also known as phosphoantigens (pAgs). HMBPP was recently shown to increase blood meal appetite in malaria mosquitoes. Both IPP and HMBPP are metabolites produced by the normal gut microbiota and apicomplexan parasites such as Plasmodium.
View Article and Find Full Text PDFAn Bras Dermatol
August 2025
Department of Pathology, Faculty of Medicine, Universidade de São Paulo, São Paulo, SP, Brazil; Instituto de Medicina Tropical da Faculty of Medicine, Universidade de São Paulo, São Paulo, SP, Brazil.
Background: Leprosy is a chronic infectious disease marked by complex immune interactions, yet the roles of specific B-lymphocyte subsets in its pathology are poorly understood.
Objectives: To investigate the presence and distribution of B-cell subsets, including B1 cells, Marginal Zone (MZ) B-cells, Regulatory B-cells (Bregs), and Effector-1 B-cells (Be1), across different clinical forms of leprosy and reactional states.
Methods: Immunohistochemical and morphometric analyses were performed on skin lesions from patients with various clinical presentations of leprosy.
J Clin Immunol
August 2025
National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.
Background And Objectives: Germline pathogenic variants in the mucosa-associated lymphoid tissue lymphoma translocation gene 1 (MALT1) encodes a caspase-like protease that plays a crucial role in the caspase recruitment domain (CARD)-B-cell lymphoma 10 (BCL10)-MALT1 (CBM) complex. This complex mediates the activation of nuclear factor-kB (NF-kB) pathway and are associated with diverse human diseases including combine immunodeficiency (CID), lymphoproliferation and others. This study aimed to determine the underlying cause of immune deficiency and immune dysregulation in a patient presented with recurrent respiratory infections, aphthous ulcers, dermatitis, chronic diarrhea, failure to thrive and early death.
View Article and Find Full Text PDFAtherosclerosis
August 2025
Jiangsu Key Laboratory of Infection and Immunity, Children's Hospital of Soochow University, Institutes of Biology & Medical Sciences, Soochow Medical College of Soochow University, Suzhou, 215123, China; MOE Key Laboratory of Geriatric Diseases and Immunology, Suzhou Medical College of Soochow Univ
Background And Aims: We previously reported that one Cd19 allele inactivation by insertion of the Cre-expressing cassette specifically impairs the development of B1a and marginal zone B (MZB) cells but enhances humoral responses in vivo. Because B1 and MZB cells are considered atheroprotective, this study aims to investigate the potential impact of Cd19 haplodeficiency on atherosclerosis.
Methods: Cd19 and Cd19 littermates on Ldlr background were generated and fed Western-type diet (WTD) to induce atherosclerosis.
EBioMedicine
July 2025
Department of Genetics, Evolution, Microbiology, and Immunology, Institute of Biology, University of Campinas, Campinas, SP, Brazil; Experimental Medicine Research Cluster, University of Campinas, Campinas, SP, Brazil. Electronic address:
Background: Oropouche virus (OROV) is a neglected insect-borne orthobunyavirus that causes a febrile illness, neurological disease, and pregnancy complications in humans across an endemic area spanning South and Central America. The host factors associated with disease pathogenesis have nonetheless remained obscure, and little is known about the immune determinants of protection against OROV.
Methods: We tracked morbidity, mortality, viral loads, and serum neutralisation in wild-type (WT), Rag1, CD19-CreIfnar, and CD19-CreMyD88 mice and performed immunophenotyping experiments, passive serum transfers, and adoptive cell transfers to determine how early antibody responses and B cell subsets control viral replication and dissemination to the central nervous system after infection with OROV.