The danger model of immunity and tolerance holds that antigen-presenting cells (APCs), activated by stress, injury, or necrosis, but not by physiological (apoptotic) cell death, initiate adaptive immune responses. APC activation is fundamentally associated with binding of CD40 to its ligand CD154. Platelets express CD154 upon activation and are thus potential primal danger signals linking the homeostatic response to trauma to activation of the acquired immune system. Previously, we showed that platelets can undergo gradient-driven migration, or chemotaxis, toward supernatants from cells injured by repeated freeze/thaws, UV light, or ischemia/reperfusion. Herein, we demonstrate that platelet-derived CD154 induces immature dendritic cell maturation with upregulation of costimulatory molecules and IL-12p40 production. Overall, these results provide a mechanism for platelet activation of APC facilitating the induction of adaptive immunity in environments of cell injury.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.exphem.2003.11.004 | DOI Listing |
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
January 2025
Hematologic Disease Center, First Affiliated Hospital of Xinjiang Medical University, Xinjiang Uygur Autonomous Region Research Institute of Hematology, Xinjiang Medical University, Urumqi, Xinjiang Uygur Autonomous Region, Wulumuqi 830011, China. *Corresponding author, E-mail:
Objective This study investigated the regulatory effect of high mobility group protein B1 (HMGB1) in the peripheral blood of patients with primary immune thrombocytopenia (ITP) on myeloid dendritic cells (mDC) and Th17/regulatory T cells (Treg) balance. Methods The study enrolled 30 newly diagnosed ITP patients and 30 healthy controls.Flow cytometry was used to measure the proportion of mDC, Th17, and Treg cells in the peripheral blood of ITP patients and healthy controls.
View Article and Find Full Text PDFMol Ther
January 2025
Department of Biological Engineering, Massachusetts Institute of Technology; Cambridge, MA, USA, 02139; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology; Cambridge, MA, USA, 02139; Department of Chemical Engineering, Massachusetts Institute of Technology; Cambridge, MA, USA, 02139; Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, and Harvard University; Cambridge, MA, USA, 02139; Howard Hughes Medical Institute; Chevy Chase, MD, USA, 20815; Department of Materials Science of Engineering; Massachusetts Institute of Technology; Cambridge, MA, USA, 02139. Electronic address:
mRNA delivered using lipid nanoparticles (LNPs) has become an important subunit vaccine modality, but mechanisms of action for mRNA vaccines remain incompletely understood. Here, we synthesized a metal chelator-lipid conjugate enabling positron emission tomography (PET) tracer labeling of LNP/mRNA vaccines for quantitative visualization of vaccine trafficking in live mice and non-human primates (NHPs). Following i.
View Article and Find Full Text PDFNutrients
December 2024
Nihonbashi Cardiology Clinic, Kyodo Bldg. #201, 13-4 Nihonbashi Kodenmacho, Chuo-ku, Tokyo 103-0001, Japan.
Background/objectives: GCL1815 is a lactic acid bacterium thought to activate dendritic cells. This randomized, placebo-controlled, double-blind study aimed to evaluate the effects of GCL1815 on human dendritic cells and the onset of the common cold.
Methods: Two hundred participants were divided into two groups and took capsules containing either six billion GCL1815 cells or placebo for 8 weeks.
Int J Mol Sci
December 2024
College of Life Sciences and Biotechnology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea.
Bone marrow stromal antigen 2 (BST2) is a host-restriction factor that plays multiple roles in the antiviral defense of innate immune responses, including the inhibition of viral particle release from virus-infected cells. BST2 may also be involved in the endothelial adhesion and migration of monocytes, but its importance in the immune system is still unclear. Immune cell adhesion and migration are closely related to the initiation of immune responses.
View Article and Find Full Text PDFJ Immunother Cancer
December 2024
Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois, USA
Background: The use of immune checkpoint inhibitors (CPIs) has become a dominant regimen in modern cancer therapy, however immune resistance induced by tumor-associated macrophages (TAMs) with immune suppressive and evasion properties limits responses. Therefore, the rational design of immune modulators that can control the immune suppressive properties of TAMs and polarize them, as well as dendritic cells (DCs), toward a more proinflammatory phenotype is a principal objective in cancer immunotherapy.
Methods: Here, using a protein engineering approach to enhance cytokine residence in the tumor microenvironment, we examined combined stimulation of the myeloid compartment via tumor stroma-binding granulocyte-macrophage colony-stimulating factor (GM-CSF) to enhance responses in both DCs and T cells via stroma-binding interleukin-12 (IL-12).
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!