M cells are a subset of mucosal epithelial cells with specialized capability to transport antigens across the mucosal barrier, but there is limited information on antigen transfer in the subepithelial zone due to the challenges in tracking microparticles and antigens that are transcytosed by this unique cell. Using transgenic reporter mice expressing dsRed in the cytoplasm of M cells and EGFP in myeloid cells, we observed that the M cell basolateral pocket hosts a close interaction between B lymphocytes and dendritic cells. Interestingly, we identified a population of previously undescribed M cell-derived vesicles (MCM) that are constitutively shed into the subepithelial space and readily taken up by CX3CR1(+)CD11b(+) CD11c(+) dendritic cells. These MCM are characterized by their cytoplasmic dsRed confirming their origin from the M cell cytoplasm. MCM showed preferential colocalization in dendritic cells with transcytosed bacteria but not transcytosed polystyrene beads, indicating a selective sorting of cargo fate in the subepithelial zone. The size and number of MCM were found to be upregulated by bacterial transcytosis and soluble toll-like receptor 2 (TLR2) agonist, further pointing to dynamic regulation of this mechanism. These results suggest that MCM provide a unique function by delivering to dendritic cells, various materials such as M cell-derived proteins, effector proteins, toxins, and particles found in the M cell cytoplasm during infection or surveillance.
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http://dx.doi.org/10.1080/21688370.2015.1004975 | DOI Listing |
Biomaterials
January 2025
Department of Pharmacy of Puning People's Hospital (Guangdong Postdoctoral Innovation Practice Base of Jinan University), Department of Chemistry, State Key Laboratory of Bioactive Molecules and Druggability Assessment, MOE Key Laboratory of Tumor Molecular Biology, Jinan University, Guangdong, 510632, China. Electronic address:
Developing translational nanoradiosensitizers with multiple activities in sensitizing tumor cells and re-shaping tumor immunosuppressive microenvironments are urgently desired for addressing the poor therapeutic efficacy of radiotherapy in clinic. Inspired by the anaerobic and immunoagonist properties of the probiotic (bifidobacterium longum, BL), herein, a biomimetic Selenium nanoradiosensitizer in situ-formed on the surface of the probiotic (BL@SeNPs) is developed in a facile method to potentiate radiotherapy. BL@SeNPs selectively target to hypoxia regions of tumors and then anchor on the surface of tumor cells to inhibit its proliferation.
View Article and Find Full Text PDFCell Rep
January 2025
Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB T6G 1Z2, Canada; Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB T6G 2R3, Canada. Electronic address:
Patients with colorectal cancers (CRCs) that have microsatellite instability (MSI) (MSI CRCs) face a better prognosis than those with the more common chromosomal instability (CIN) subtype (CIN CRCs) due to improved T cell-mediated anti-tumor immune responses. Previous investigations identified the cytosolic DNA (cyDNA) sensor STING as necessary for chemokine-mediated T cell recruitment in MSI CRCs. Here, we find that cyDNA from MSI CRC cells is inherently more capable of inducing STING activation and improves cytotoxic T cell activation by dendritic cells (DCs).
View Article and Find Full Text PDFTransl Psychiatry
January 2025
Department of Neuropsychiatry, Dongguk University, School of Medicine, Seoul, Republic of Korea.
Autism spectrum disorder (ASD) is linked to ion channel dysfunction, including chloride voltage-gated channel-4 (CLCN4). We generated Clcn4 knockout (KO) mice by deleting exon 5 of chromosome 7 in the C57BL/6 mice. Clcn4 KO exhibited reduced social interaction and increased repetitive behaviors assessed using three-chamber and marble burying tests.
View Article and Find Full Text PDFCancer Lett
January 2025
. Department of Thoracic Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China. Electronic address:
Tertiary lymphoid structures (TLSs) are ectopic immune cell clusters formed in nonlymphoid tissues affected by persistent inflammation, such as in cancer and prolonged infections. They have features of the structure and function of secondary lymphoid organs, featuring central CD20+ B cells, surrounded by CD3+ T cells, CD21+ follicular dendritic cells, and CD68+ macrophages, with a complex vascular system. TLS formation is governed by lymphotoxin-α1β2, TNF, and chemokines like CCL19, CCL21, and CXCL13, differing from secondary lymphoid organ development in developing later in life at sites of chronic inflammation.
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry (Shaanxi Normal University), The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China. Electronic address:
Inflammation underlies a wide variety of physiological and pathological processes, the Lipopolysaccharide (LPS)-induced inflammation model is widely recognized as a classical inflammatory paradigm, while Transforming growth factor-β (TGF-β) serves as a potent immunosuppressant capable of inhibiting immune responses and mitigating inflammation. However, its in vivo instability and the high cost associated with purification have imposed limitations on its clinical application. Therefore, we propose a therapeutic strategy for genetically modifying extracellular vesicles (HEVs) derived from HEK-293 T cells to incorporate TGF-β which holds potential for mitigating LPS-induced inflammation.
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