The B cell receptor (BCR) interacts with foreign antigens to mediate B cell activation and secretion of antibodies. B cell activation begins with initiation of signaling pathways, such as NFAT, NF-κB, and MAPK, and endocytosis of the BCR-antigen complex. Many studies have investigated the signaling pathways associated with BCR activation, and this work has led to significant advances in drug therapies to treat cancer and autoimmune diseases that are linked to aberrant BCR signaling. Less is known, however, about the mechanisms of BCR endocytosis and the role endocytosis plays in B cell pathogenesis. This chapter will review key characteristics of the BCR, including a review of signaling pathways, and endocytic mechanisms associated with the activated BCR. We will also review recent studies investigating the role of BCR endocytosis disease pathogenesis.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/bs.pmbts.2022.08.003 | DOI Listing |
Sci Adv
November 2024
Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, WA, USA.
Life Sci Alliance
January 2025
Laboratory of Immune Cell Biology. Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
B cells rapidly adapt their endocytic pathway to promote the uptake and processing of extracellular antigens recognized through the B-cell receptor (BCR). The mechanisms coupling changes in endomembrane trafficking to the capacity of B cells to screen for antigens within lymphoid tissues remain unaddressed. We investigated the role of SNX5, a member of the sorting nexin family, which interacts with endocytic membranes to regulate vesicular trafficking and macropinocytosis.
View Article and Find Full Text PDFJ Immunol
November 2024
Department of Neurology, University of California, Irvine, Irvine, CA.
N-glycan branching is a potent and multifaceted negative regulator of proinflammatory T cell and B cell function. By promoting multivalent galectin-glycoprotein lattice formation at the cell surface, branching regulates clustering and/or endocytosis of the TCR complex (TCR+CD4/CD8), CD45, CD25, BCR, TLR2 and TLR4 to inhibit T cell and B cell activation/proliferation and proinflammatory TH1 and TH17 over TH2 and induced T regulatory cell responses. In addition, branching promotes cell surface retention of the growth inhibitory receptor CTLA-4.
View Article and Find Full Text PDFiScience
July 2024
Immunology Research Center, National Health Research Institutes, Zhunan Town, Miaoli County 350401, Taiwan.
Phosphatase and tensin homolog (PTEN) is vital for B cell development, acting as a key negative regulator in the PI3K signaling pathway. We used CD23-cre to generate PTEN-conditional knockout mice (CD23-cKO) to examine the impact of PTEN mutation on peripheral B cells. Unlike mb1-cre-mediated PTEN deletion in early B cells, CD23-cKO mutants exhibited systemic inflammation with increased IL-6 production in mature B cells upon CpG stimulation.
View Article and Find Full Text PDFImmunohorizons
April 2024
Department of Immunology and Microbial Disease, Albany Medical College, Albany, NY.
The BCR allows for Ag-driven B cell activation and subsequent Ag endocytosis, processing, and presentation to recruit T cell help. Core drivers of BCR signaling and endocytosis are motifs within the receptor's cytoplasmic tail (primarily CD79). However, BCR function can be tuned by other proximal cellular elements, such as CD20 and membrane lipid microdomains.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!