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Current Stem Cell Research & Therapy Sep 2013Dendritic cells (DC) are important antigen presenting cells (APC) which induce and control the adaptive immune response. In spleen alone, multiple DC subsets can be... (Review)
Review
Dendritic cells (DC) are important antigen presenting cells (APC) which induce and control the adaptive immune response. In spleen alone, multiple DC subsets can be distinguished by cell surface marker phenotype. Most of these have been shown to develop from progenitors in bone marrow and to seed lymphoid and tissue sites during development. This study advances in vitro methodology for hematopoiesis of dendritic-like cells from progenitors in spleen. Since spleen progenitors undergo differentiation in vitro to produce these cells, the possibility exists that spleen represents a specific niche for differentiation of this subset. The fact that an equivalent cell subset has been shown to exist in spleen also supports that hypothesis. Studies have been directed at investigating the specific functional role of this novel subset as an APC accessible to blood-borne antigen, as well as the conditions under which hematopoiesis is initiated in spleen, and the type of progenitor involved.
Topics: Adaptive Immunity; Animals; Antigen-Presenting Cells; Bone Marrow Cells; Cell Differentiation; Dendritic Cells; Flow Cytometry; Hematopoiesis; Mice; Spleen
PubMed: 23971833
DOI: 10.2174/1574888x113089990050 -
Immunology Aug 2011Dendritic cells (DCs) are professional antigen-presenting cells that are critical for induction of adaptive immunity and tolerance. Traditionally DCs have been divided... (Review)
Review
Dendritic cells (DCs) are professional antigen-presenting cells that are critical for induction of adaptive immunity and tolerance. Traditionally DCs have been divided into two discrete subtypes, which comprise conventional and non-conventional DCs. They are distributed across various organs in the body and comprise a heterogeneous population, which has been shown to display differences in terms of surface marker expression, function and origins. Recent studies have shed new light on the process of DC differentiation and distribution of DC subtypes in various organs. Although monocytes, macrophages and DCs share a common macrophage-DC progenitor, a common DC progenitor population has been identified that exclusively gives rise to DCs and not monocytes or macrophages. In this review, we discuss the recent advances in our understanding of DC differentiation and subtypes and provide a comprehensive overview of various DC subtypes with emphasis on their function and origins. Furthermore, in light of recent developments in the field of DC biology, we classify DCs based on the precursor populations from which the various DC subsets originate. We classify DCs derived from common DC progenitor and pre-DC populations as conventional DCs, which includes both migratory and lymphoid-resident DC subsets and classify monocyte-derived DCs and plasmacytoid DCs as non-conventional DCs.
Topics: Animals; Cell Differentiation; Dendritic Cells; Humans; Immune System
PubMed: 21627652
DOI: 10.1111/j.1365-2567.2011.03457.x -
American Journal of Physiology. Cell... Jun 2011Dendritic cells (DCs) are highly versatile antigen-presenting cells critically involved in both innate and adaptive immunity as well as maintenance of self-tolerance. DC... (Review)
Review
Dendritic cells (DCs) are highly versatile antigen-presenting cells critically involved in both innate and adaptive immunity as well as maintenance of self-tolerance. DC function is governed by Ca(2+) signaling, which directs the DC responses to diverse antigens, including Toll-like receptor ligands, intact bacteria, and microbial toxins. Ca(2+)-sensitive DC functions include DC activation, maturation, migration, and formation of immunological synapses with T cells. Moreover, alterations of cytosolic Ca(2+) trigger immune suppression or switch off DC activity. Ca(2+) signals are generated by the orchestration of Ca(2+) transport processes across plasma, endoplasmic reticulum, and inner mitochondrial membrane. These processes include active pumping of Ca(2+), Ca(2+)/Na(+) antiport, and electrodiffusion through Ca(2+)-permeable channels or uniporters. Ca(2+) channels in the plasma membrane such as Ca(2+) release-activated Ca(2+) or L-type Ca(2+) channels are tightly regulated by the membrane potential which in turn depends on the activity of voltage-gated K(+) or Ca(2+)-activated nonselective cation channels. The rapidly growing knowledge on the function and regulation of these membrane transport proteins provides novel insight into pathophysiological mechanisms underlying dysfunction of the immune system and opens novel therapeutic opportunity to favorably influence the function of the immune system.
Topics: Animals; Calcium; Calcium Signaling; Cell Differentiation; Dendritic Cells; Humans; Ion Channels; Membrane Transport Proteins; T-Lymphocytes
PubMed: 21451105
DOI: 10.1152/ajpcell.00039.2011 -
Nihon Rinsho. Japanese Journal of... Dec 2001Dendritic cells(DC) are most powerful antigen presenting cells for the induction of antigen specific T cell response. They have been successfully used in clinical pilot... (Review)
Review
Dendritic cells(DC) are most powerful antigen presenting cells for the induction of antigen specific T cell response. They have been successfully used in clinical pilot study to induce tumor specific immunity as well as clinical response in selected patients. Here we report the ability of DC therapy against chronic myelogenous leukemia(CML). Three patients with CML received a series of four infusions of CML-specific bcr/abl peptide-pulsed autologous DCs. Vaccination was well tolerated. No physical sign of autoimmunity was detected in any of patients. DC vaccination induced delayed-type hypersensitivity(DTH) reactivity toward KLH in all patients, as well as positive DTH reaction to peptide-pulsed DC in one patient. Clinical responses have been measured with no patients. Further studies are necessary to demonstrate clinical effectiveness and impact on the survival of CML patients.
Topics: Dendritic Cells; Humans; Hypersensitivity, Delayed; Immunotherapy, Adoptive; Leukemia, Myelogenous, Chronic, BCR-ABL Positive
PubMed: 11766350
DOI: No ID Found -
Medical Microbiology and Immunology Mar 2007Because of their anatomical distribution epidermal Langerhans cells (LCs) are discussed to be crucial for antigen uptake and subsequent presentation to naïve T cells in... (Review)
Review
Because of their anatomical distribution epidermal Langerhans cells (LCs) are discussed to be crucial for antigen uptake and subsequent presentation to naïve T cells in skin-draining lymph nodes. The use of LC-specific markers like Langerin or knock-in mice expressing green fluorescent protein under the control of the Langerin promotor now facilitates the dissection of LCs from other dendritic cell (DC) subsets. Surprisingly, current data indicate that LCs are not generally involved in the induction of cellular immune responses. Moreover, the widely accepted paradigm postulating that LCs in principle act as T cell activators is contested by recent publications. Consequently, the biological role of LCs, in particular in cutaneous immune responses, needs to be revisited. The experimental model of leishmaniasis represents a suitable model to study the origin of an antigen-specific T cell response in mice. With this model the transport and presentation of skin derived Leishmania (L.) major antigens can be monitored in vivo. Furthermore, the quality of T cell-DC interactions can be determined. Considering recent progress in LC research we propose a novel concept of LCs in T cell meditated immunity against L. major parasites.
Topics: Animals; Antigen-Presenting Cells; Antigens, Protozoan; Cytokines; Dendritic Cells; Immunity, Cellular; Langerhans Cells; Leishmania major; Leishmaniasis, Cutaneous; Lymph Nodes; Mice; Skin; T-Lymphocytes
PubMed: 16786361
DOI: 10.1007/s00430-006-0023-0 -
Research in Immunology 1989Clinical aspects of dendritic cells have yet to be studied intensively. One obstacle, that of isolating and identifying dendritic cells from human blood and other... (Review)
Review
Clinical aspects of dendritic cells have yet to be studied intensively. One obstacle, that of isolating and identifying dendritic cells from human blood and other tissues like skin and tonsil, is being overcome, although the field would be facilitated by dendritic-cell-specific monoclonals or other probes. Many of the specializations that dendritic cells exhibit as antigen-presenting cells in other mammals are being verified in man. New properties, particularly their capacity to induce clonal expansion of T cells and to be infected with retroviruses, have become evident. Four areas where it may be productive to give more attention to dendritic cells are transplantation, protective T-cell immunity, autoimmunity and HIV-1 infection.
Topics: Acquired Immunodeficiency Syndrome; Autoimmunity; Cell Differentiation; Dendritic Cells; HIV-1; Humans; Immunity; Phenotype; Transplantation Immunology; Vaccination
PubMed: 2697915
DOI: 10.1016/0923-2494(89)90054-0 -
Clinical Medicine & Research Aug 2005The paradigm of tolerogenic/immature versus inflammatory/mature dendritic cells has dominated the recent literature regarding the role of these antigen-presenting cells... (Review)
Review
The paradigm of tolerogenic/immature versus inflammatory/mature dendritic cells has dominated the recent literature regarding the role of these antigen-presenting cells in mediating immune homeostasis or self-tolerance and response to pathogens, respectively. This issue is further complicated by the identification of distinct subtypes of dendritic cells that exhibit different antigen-presenting cell effector functions. The discovery of pathogen-associated molecular patterns and toll-like receptors provides the mechanistic basis for dendritic cell recognition of specific pathogens and induction of appropriate innate and adaptive immune responses. Only recently has insight been gained into how dendritic cells contribute to establishing and/or maintaining immunological tolerance to self. Soluble and cellular mediators have been reported to effectively regulate the function of dendritic cells by inducing several outcomes ranging from non-inflammatory dendritic cells that lack the ability to induce T lymphocyte activation to dendritic cells that actively suppress T lymphocyte responses. A thorough discussion of these stimuli and their outcomes is essential to understanding the potential for modulating dendritic cell function in the treatment of inflammatory disease conditions.
Topics: Animals; Apoptosis; Dendritic Cells; Humans; Immunity, Cellular; Immunologic Factors; T-Lymphocytes
PubMed: 16160071
DOI: 10.3121/cmr.3.3.166 -
Cellular & Molecular Immunology Dec 2005Appropriate in vivo control of plasmacytoid dendritic cell (pDC) recruitment and activation is a fundamental requirement for defense against viral infection. During this... (Review)
Review
Appropriate in vivo control of plasmacytoid dendritic cell (pDC) recruitment and activation is a fundamental requirement for defense against viral infection. During this process, a pivotal event that influences the outcome of viral infection is the production of high levels of type I interferon by pDCs. In particular, recent research findings showed that pDCs not only shape the nature of innate resistance, but are also responsible for the successful transition from innate to adaptive immunity for viral resistance. In addition, pDCs can differentiate into antigen presenting cells that may regulate tolerance to a given pathogen. Importantly, in a series of recent clinical studies, pDCs appeared to be defective in number and function in conditions of chronic viral diseases such as infected with HIV-1, HBV or HCV. pDC-associated clinical antiviral therapy is also emerging. This review describes research findings examining the functional and antiviral properties of in vivo pDC plasticity.
Topics: Animals; Dendritic Cells; Humans; Immunity, Innate; Immunotherapy; Virus Diseases; Viruses
PubMed: 16426490
DOI: No ID Found -
Seminars in Immunopathology Feb 2017Dendritic cells (DC) are unique hematopoietic cells, linking innate and adaptive immune responses. In particular, they are considered as the most potent antigen... (Review)
Review
Dendritic cells (DC) are unique hematopoietic cells, linking innate and adaptive immune responses. In particular, they are considered as the most potent antigen presenting cells, governing both T cell immunity and tolerance. In view of their exceptional ability to present antigen and to interact with T cells, DC play distinct roles in shaping T cell development, differentiation and function. The outcome of the DC-T cell interaction is determined by the state of DC maturation, the type of DC subset, the cytokine microenvironment and the tissue location. Both regulatory T cells (Tregs) and DC are indispensable for maintaining central and peripheral tolerance. Over the past decade, accumulating data indicate that DC critically contribute to Treg differentiation and homeostasis.
Topics: Animals; Antigen Presentation; Autoimmune Diseases; Biomarkers; Cell Communication; Cell Differentiation; Dendritic Cells; Homeostasis; Humans; Immune Tolerance; Immunotherapy; Organ Specificity; Phenotype; Signal Transduction; T-Lymphocyte Subsets
PubMed: 27456849
DOI: 10.1007/s00281-016-0583-z -
Clinical Journal of Oncology Nursing Aug 2005Once believed to be part of the nervous system, dendritic cells (DCs) now are known to be potent antigen-presenting cells of the immune system. Upon capturing a foreign... (Review)
Review
Once believed to be part of the nervous system, dendritic cells (DCs) now are known to be potent antigen-presenting cells of the immune system. Upon capturing a foreign antigen, the immature DC matures as it travels to the T cells to activate an immune response. DCs can be categorized into two main subsets: DC1s and DC2s. DC1s, also called myeloid-related DCs, arise from early-precursor cells or monocytes and play a role in initiating immune responses against antigens such as cancer cells. Various cytokines stimulate the growth and differentiation of DCs, such as granulocyte macrophage-colony-stimulating factor. DC research is evolving rapidly as a clinical therapy; therefore, nurses should appreciate the cell's mechanisms of action.
Topics: Dendritic Cells; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Recombinant Proteins
PubMed: 16117213
DOI: 10.1188/05.CJON.460-464