• Hence cutaneous histiocytoma is a localized epidermal Langerhans cell tumor, and the rare examples of systemic spread of histiocytoma are best characterized as Langerhans cell histiocytosis (LCH) similar to that observed in humans. (wikipedia.org)
  • Langerhans cell histiocytosis (LCH) is a group of idiopathic disorders characterized by the presence of cells with characteristics similar to bone marrow-derived Langerhans cells juxtaposed against a backdrop of hematopoietic cells, including T-cells, macrophages, and eosinophils. (medscape.com)
  • The term Langerhans cell histiocytosis is generally preferred to the older term, histiocytosis X. This newer name emphasizes the histogenesis of the condition by specifying the type of lesional cell and removes the connotation of the unknown ("X") because its cellular basis has now been clarified. (medscape.com)
  • The working group of the Histiocyte Society divided histocytic disorders into three groups: (1) dendritic cell histiocytosis, (2) macrophage-related disorders, and (3) malignant histiocytosis. (medscape.com)
  • More recently, histiocytic diseases have been reclassified into five groups: (1) Langerhans-related, (2) cutaneous and mucocutaneous, (3) malignant histiocytosis, (4) Rosai-Dorfman disease, and (5) hemophagocytic lymphohistiocytosis and macrophage activation syndrome. (medscape.com)
  • The pathogenesis of Langerhans cell histiocytosis (LCH) is unknown. (medscape.com)
  • Currently, the preferred term is Langerhans cell histiocytosis. (thedoctorsdoctor.com)
  • Langerhans cell histiocytosis presenting in the neonatal period: a retrospective case series. (thedoctorsdoctor.com)
  • OBJECTIVES: To describe the morphologic characteristics of skin lesions, extent of extracutaneous disease, and outcomes in patients with neonatal presentation of Langerhans cell histiocytosis (LCH), and to examine clinical predictors of disease prognosis. (thedoctorsdoctor.com)
  • Epidemiologic study of Langerhans cell histiocytosis in children. (thedoctorsdoctor.com)
  • OBJECTIVE: The etiology and pathogenesis of Langerhans cell histiocytosis (LCH) remain poorly understood. (thedoctorsdoctor.com)
  • Histiocytic sarcoma complex (immunohistochemical features of dendritic cells, possibly interdigitating or perivascular DCs) 3.a. (wikipedia.org)
  • Genotyping of 69 histiocytic lesions revealed that 23/48 Langerhans cell lesions were BRAF -V600E-mutant whereas all non-Langerhans cell lesions (including dendritic cell sarcoma, juvenile xanthogranuloma, Rosai-Dorfman disease, and granular cell tumor) were wild-type. (oncotarget.com)
  • In conclusion, BRAF mutations in histiocytic proliferations are restricted to lesions of the Langerhans-cell type. (oncotarget.com)
  • In the context of cancer, appropriately activated DCs can induce anti-tumor immunity by activating innate immune cells and tumor-specific lymphocytes that target cancer cells. (mdpi.com)
  • Since EMPD is a skin adenocarcinoma of apocrine gland origin that expresses high levels of RANKL and matrix metalloproteinase (MMP) 7, and EMPD is associated with the presence of RANK + M2 macrophages, we hypothesized that tumor-associated macrophages (TAMs) in adenocarcinomas such as PCAC might also express RANKL and MMP7. (iiarjournals.org)
  • Of these, tumor-associated macrophages (TAMs) and regulatory T-cells (Tregs) create an immunosuppressive microenvironment through various pathways. (iiarjournals.org)
  • For example, Paget's cells release soluble receptor activator of nuclear factor kappa-B ligand (sRANKL) into the tumor microenvironment, stimulating RANK + TAMs to produce CCL17, which recruits Tregs into the lesional skin of patients with extramammary Paget's disease (EMPD) ( 11 , 17 ). (iiarjournals.org)
  • Arguments supporting the reactive nature of LCH include the occurrence of spontaneous remissions, the extensive elaboration of multiple cytokines by dendritic cells and T-cells (the so-called cytokine storm) in LCH lesions, and the good survival rate in patients without organ dysfunction. (medscape.com)
  • A 2010 study comparing gene expression of cells expressing CD207 (a marker of Langerhans cells) in LCH lesions with epidermal CD207+ control cells identified differential expression of more than 2000 genes between these 2 subsets. (medscape.com)
  • Dendritic cell as sentinel of the immune system plays an irreplaceable role. (medsci.org)
  • We focus on the essential functions of dendritic cell in severe SARS-CoV-2 infection. (medsci.org)
  • Canine cutaneous histiocytoma (derived from specialised epidermic dendritic cells, the Langerhans cells) 2. (wikipedia.org)
  • Epidermal invasion in histiocytoma, or presence of simultaneous multiple histiocytomas, especially in aged dogs, can appear similar to MF or non-epidermotropic cutaneous lymphoma (NECL). (wikipedia.org)
  • Specifically, a variety of other cellular populations have been identified that possess phenotypic characteristics similar to Langerhans cells, including expression of CD207 and Birbeck granules. (medscape.com)
  • DR+ epidermal macrophage induction, and noma in young women: An evaluation of the Langerhans cell depletion. (who.int)
  • Notably, LCH cells have been found to express markers of both resting epidermal Langerhans cells (CD1a, intracellular major histocompatibility complex II [MHCII], Birbeck granules) and activated Langerhans cells (including CD54 and CD58). (medscape.com)
  • 10] Interestingly, this analysis found no differences in expression of proliferation markers between these subsets of CD207+ cells, consistent with the hypothesis that LCH may be a disease of abnormal cellular accumulation. (medscape.com)
  • The term "oncotarget" encompasses all molecules, pathways, cellular functions, cell types, and even tissues that can be viewed as targets relevant to cancer as well as other diseases. (oncotarget.com)
  • Epidermal invasion by cells of histiocytoma frequently occurs and intra-epidermal nests of histiocytes resemble Pautrier's aggregates, characteristically found in epidermotropic lymphoma (Mycosis Fungoides or MF). (wikipedia.org)
  • Immunohistochemical staining of MMP1 and MMP25 as well as chemokine (C-C motif) ligand (CCL) 5 in the lesional skin from five patients with PCAC showed a substantial number of MMP1-bearing cells and MMP25-bearing cells, as well as CCL5-producing cells, that were distributed in the lesional skin. (iiarjournals.org)
  • Dendritic cells-based therapeutic approach may be a potential strategy for SARS-CoV-2 infection. (medsci.org)
  • For example, TAMs suppress effector T-cells through immune checkpoint molecules, such as those of the programmed cell death 1 (PD-1) ( 7 ) and cytotoxic T-lymphocyte-associated protein 4 (CTLA4) ( 8 , 9 ) pathways. (iiarjournals.org)
  • On the other hand, the infiltration of organs by a monoclonal population of aberrant cells, the possibility of lethal evolution, and the cancer-based modalities of successful treatment are all consistent with a neoplastic process. (medscape.com)
  • Imiquimod induced an IFN signature and led to reduced infiltration of inflammatory cells. (cnrs.fr)
  • OBJECTIVE: The role of plasmacytoid dendritic cells (PDCs) and type I interferons (IFNs) in rheumatoid arthritis (RA) remains a subject of controversy. (cnrs.fr)
  • These differences were found in genes involved in cell cycle regulation, apoptosis, cell signaling, metastasis, and myeloid differentiation. (medscape.com)
  • Langerhans cell histiocytoses are all defined by the presence of a unique ultrastructural organelle, the Birbeck granule. (thedoctorsdoctor.com)
  • Dendritic cells (DCs) are specialized antigen-presenting cells that have a notable role in the initiation and regulation of innate and adaptive immune responses. (mdpi.com)