• maturation
  • We also demonstrate a role for autocrine type I IFN signaling in bacterial LPS-induced DC maturation, although, in the context of LPS stimulation, this mechanism is not so critical for CD8 T cell activation (promotes IFN-γ production but not proliferation or granzyme B production). (jimmunol.org)
  • After birth, the decline of T-cell function begins with the progressive involution of the thymus, which is the organ essential for T-cell maturation following the migration of precursor cells from the bone marrow. (wikipedia.org)
  • Bone marrow is responsible for both the creation of T cells and the production and maturation of B cells. (wikipedia.org)
  • Thymic
  • This age-associated decrease of thymic epithelial volume results in a reduction/exhaustion on the number of thymocytes (i.e. pre-mature T-cells), thus reducing output of peripheral naïve T-cells. (wikipedia.org)
  • Together with the age-related thymic involution, and the consequent age-related decrease of thymic output of new T cells, this situation leaves the body practically devoid of virgin T cells, which makes the body more prone to a variety of infectious and non-infectious diseases. (wikipedia.org)
  • phagocytic cells
  • Supposedly, this separation from the sites of earliest antigen processing and capture provide a protected environment in which opsonized antigens can be displayed for a long time without being proteolyzed or removed by phagocytic cells. (wikipedia.org)
  • lysosomes
  • extracellular proteins are endocytosed, digested in lysosomes, and the resulting epitopic peptide fragments are loaded onto MHC class II molecules prior to their migration to the cell surface. (wikipedia.org)
  • As in phagocytic immune cells, the resulting phagosome may be merged with lysosomes containing digestive enzymes, forming a phagolysosome. (wikipedia.org)
  • molecules
  • Because cancer cells typically fail to express the repertoire of costimulatory molecules required for stimulating T cells directly, adaptive immune recognition is likely accomplished through an indirect mechanism that exploits the capture of dying tumor cells by host mononuclear phagocytes ( 6 ). (aacrjournals.org)
  • These molecules are constitutively expressed in professional, immune antigen presenting cells, but may also be induced on other cells by interferon γ. (wikipedia.org)
  • Adhesion between FDCs and B cells is mediated by ICAM-1 (CD54)-LFA-1 (CD11a) and VCAM-VLA-4 molecules. (wikipedia.org)
  • Various molecular markers can serve as eat-me signals, particularly a change in composition of the cell membrane, modifications of molecules on the cell surface, changed charge on the plasma membrane, or indirectly the extracellular bridging molecules. (wikipedia.org)
  • Some molecules naturally present on cells can also work as eat-me signals after certain modifications. (wikipedia.org)
  • Additionally, some intracellular molecules are displayed on the cell surface after induction of the apoptotic program to ease the recognition. (wikipedia.org)
  • Extracellular bridging molecules are serum proteins which facilitate connection between apoptotic cell and phagocyte. (wikipedia.org)
  • One of the features of an apoptotic cell is the presentation of a variety of intracellular molecules on the cell surface, such as calreticulin, phosphatidylserine (from the inner layer of the plasma membrane), annexin A1, oxidised LDL and altered glycans. (wikipedia.org)
  • The major histocompatibility complex (MHC) is a set of cell surface proteins essential for the acquired immune system to recognize foreign molecules in vertebrates, which in turn determines histocompatibility. (wikipedia.org)
  • MHC molecules mediate interactions of leukocytes, also called white blood cells (WBCs), which are immune cells, with other leukocytes or with body cells. (wikipedia.org)
  • In a cell, protein molecules of the host's own phenotype or of other biologic entities are continually synthesized and degraded. (wikipedia.org)
  • infection
  • Transfaunation of microbiota from HBM-fed preterm infants or a newly identified and cultured Propionibacterium strain, P. UF1, to germfree mice conferred protection against pathogen infection and correlated with profound increases in intestinal Th17 cells. (jci.org)
  • For example, depletion of CD8 T cells renders mice more susceptible to pulmonary infection with Cryptococcus neoformans and Paracoccidioides brasiliensis ( 3 , 4 ). (jimmunol.org)
  • During an infection, chemical signals attract phagocytes to places where the pathogen has invaded the body. (wikipedia.org)
  • A child with Bacillus Calmette-Guérin and Salmonella enteritidis infection was found to have a large homozygous deletion within the IL-12 p40 subunit gene, precluding expression of functional IL-12 p70 cytokine by activated dendritic cells and phagocytes. (wikipedia.org)
  • effector
  • The combination of brisk intratumoral CD8 + T cells and rare FoxP3 + Tregs connotes a particularly favorable prognostic index, suggesting that the balance of effector and regulatory cells might modulate disease course in some patients. (aacrjournals.org)
  • Humans
  • While in humans the level of CD14 expression can be used to differentiate non-classical and intermediate monocytes, the slan cell surface marker was shown to give an unequivocal separation of the two cell types. (wikipedia.org)
  • In humans, up to a cup (240 ml) of red blood cells can be held in the spleen and released in cases of hypovolemia. (wikipedia.org)
  • In humans, the amoebozoan entamoeba histolytica can phagocytose red blood cells. (wikipedia.org)
  • Monocyte
  • An Arbiskov cell is a modified monocyte mostly found in myeloblastomas. (wikipedia.org)
  • To test this hypothesis, we assessed the migration of monocyte-derived DCs toward HCE cell supernatants with or without lipopolysaccharide (LPS) stimulation of HCE cells and inflammatory cytokines (released by HCE cells). (jove.com)
  • There are at least three types of monocytes in human blood: The classical monocyte is characterized by high level expression of the CD14 cell surface receptor (CD14++ CD16− monocyte) The non-classical monocyte shows low level expression of CD14 and additional co-expression of the CD16 receptor (CD14+CD16++ monocyte). (wikipedia.org)
  • The term Histiocyte can also simply refer to a cell from monocyte origin outside the blood system, such as in a tissue (as in rheumatoid arthritis as palisading histiocytes surrounding fibrinoid necrosis of rheumatoid nodules). (wikipedia.org)
  • Biology
  • In molecular biology, the protein domain YopE refers to the secretion of virulence factors in Gram-negative bacteria involves transportation of the protein across two membranes to reach the cell exterior. (wikipedia.org)
  • Antigens
  • The crafting of genetic and biochemical strategies to characterize cancer antigens has yielded the insight that most patients mount tumor-specific T cell and antibody reactions ( 5 ). (aacrjournals.org)
  • Moreover, in the presence of dying cells, PTX3 restricts the cross presentation of antigens derived from dying cells. (wikipedia.org)
  • Along with dendritic cells, they are foremost among the cells that present antigens, a crucial role in initiating an immune response. (wikipedia.org)
  • They express LCAs (leucocyte common antigens) CD45, CD14, CD33, and CD4 (also expressed by T helper cells). (wikipedia.org)
  • uptake
  • Collectins (e.g. mannose-binding lectin and surfactant protein A) bind the altered surface sugars on apoptotic cell and enable easier uptake by phagocytes which recognize their complex with calreticulin. (wikipedia.org)
  • pathogen
  • Our laboratory aims to understand the underlying mechanisms controlling mononuclear phagocyte (MP) function in pathological situations such as during tumor development or the encounter with an invading pathogen. (cancer.gov)
  • We are particularly interested in the role of the microbiota: combining cellular and molecular approaches together with in vivo studies using germ-free animals we study the effect of commensals on myeloid cell function and their impact on the response to cancer therapy or to the invading pathogen. (cancer.gov)
  • helper cells
  • Whereas Mϕ-1 efficiently stimulated type 1 helper cells, Mϕ-2 only poorly supported type 1 helper function. (pnas.org)
  • tissues
  • A spectrum of host responses to cell death empowers the immune system with the dual abilities to monitor the integrity of healthy tissues and to respond rapidly to tissue injury ( 4 ). (aacrjournals.org)
  • However, during the last decade, an understanding has emerged that ROS also have important roles as signaling messengers in a multitude of pathways, in all cells, tissues, and organs. (biomedcentral.com)
  • Phagocytes are crucial in fighting infections, as well as in maintaining healthy tissues by removing dead and dying cells that have reached the end of their lifespan. (wikipedia.org)
  • Monocytes which migrate from the bloodstream to other tissues will then differentiate into tissue resident macrophages or dendritic cells. (wikipedia.org)
  • Following apoptosis, the dying cells need to be taken up into the surrounding tissues by macrophages in a process called efferocytosis. (wikipedia.org)
  • The blood does not come into direct contact with the parenchymal cells and tissues in the body (except in case of an injury causing rupture of one or more blood vessels), but constituents of the blood first exit the microvascular exchange blood vessels to become interstitial fluid, which comes into contact with the parenchymal cells of the body. (wikipedia.org)
  • apoptosis
  • ROS have been extensively implicated in T-cell hyporesponsiveness, apoptosis, and activation. (biomedcentral.com)
  • To become selected as a future memory cell, GC B cells must bind the antigen presented on FDCs, otherwise they enter apoptosis. (wikipedia.org)
  • Activated B-cells with low affinity to antigen captured on FDCs surface as well as autoreactive B-cells undergo apoptosis, whereas B cells bound to FDCs through the antigen complex, survive due to apoptosis blockage caused by interaction with FDCs. (wikipedia.org)
  • During apoptosis, these signals must be removed or changed in order not to block the ingestion by phagocyte. (wikipedia.org)
  • The other 95% of T cells begin a process of apoptosis, a form of programmed cell death. (wikipedia.org)
  • induces
  • IL-12 is a heterodimer of p40 and p35 that drives polarization of naive T cells toward type 1 helper (Th1) cells and induces the release of IFN-γ from T and natural killer cells ( 5 ). (pnas.org)
  • IL-23, similar to IL-12, induces IFN-γ secretion from T cells ( 11 ) and may be involved in type 1 immune defense against mycobacteria ( 1 , 12 ). (pnas.org)
  • proteins
  • These are important in activating critical transcription factor proteins such as STAT4 that are implicated in IL-12 signaling in T cells and NK cells. (wikipedia.org)
  • In its entirety, the MHC population is like a meter indicating the balance of proteins within the cell. (wikipedia.org)
  • cytotoxic
  • A deeper understanding of the mechanisms underlying the immunogenicity of dying cells informs the crafting of strategies that exploit endogenous or treatment-induced cancer cell death as the basis for stimulating sustained host antitumor cytotoxic reactions. (aacrjournals.org)
  • Mechanisms
  • Notwithstanding the intense effort directed toward unraveling the mechanisms underlying cancer cell death, much less attention have been devoted to understanding the host response to tumor cell demise. (aacrjournals.org)
  • In response, neoplastic cells utilize NF-κB to suppress this killing activity, but the mechanisms underlying their self-protection remain unclear. (jci.org)
  • Dendritic cells (DCs) are present in the central avascular area of inflamed corneas, but the mechanisms of their migration to this location are poorly understood. (jove.com)
  • It is unclear how exactly having the HLA-B27 tissue type increases the risk of ankylosing spondylitis and other associated inflammatory diseases, but mechanisms involving aberrant antigen presentation or T cell activation have been hypothesized. (wikipedia.org)
  • trigger
  • Autoreactive CD4 T cells that differentiate into pathogenic Th17 cells can trigger autoimmune diseases. (jci.org)
  • tumor
  • Cancer cell death occurs continually during tumor development and progression, whereas the selective killing of surviving cancer cells remains the primary objective of antineoplastic treatments. (aacrjournals.org)
  • Dying tumor cells evoke a range of host responses, dependent in part upon the mode of cell death, which may either impede or foster additional immune-mediated cancer destruction. (aacrjournals.org)
  • Although the economies of cell proliferation and accumulation dominate cell demise during disease progression, pathologic examination of established cancers typically reveals evidence for both single cell and zonal areas of tumor death. (aacrjournals.org)
  • It stimulates the production of interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) from T cells and natural killer (NK) cells, and reduces IL-4 mediated suppression of IFN-γ. (wikipedia.org)
  • Evidence also suggests that CD8 T lymphocyte cells mediate protection against Yersinia by production of cytokines (e.g., tumor necrosis factor alpha [TNF-alpha] and gamma interferon [IFN]) and by killing bacteria-associated host cells to promote internalization by neighbouring phagocytes. (wikipedia.org)
  • Signals
  • Don't-eat-me signals (also SAMPs = self-associated molecular patterns) are present on all host viable cells and actively protect the cells from engulfment. (wikipedia.org)
  • They achieve this by facilitating a detachment of phagocytes from the cell (CD31-CD31 interaction) or even sending repulsive signals towards the phagocyte (CD47-SIRPα interaction). (wikipedia.org)