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Query: UMLS:C0019621 (Langerhans cell histiocytosis)
 3,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the diagnosis of the Langerhans cell histiocytosis several monocyte and macrophag markers have been tested in the recent years. We compared the expression of macrophage and lymphoid markers in childhood and adult type Langerhans cell histiocytosis. Ten childhood and 11 adult cases were tested using paraffin sections of biopsy samples. We have examined 6 markers: the S-100, Lysozyme, CD68 macrophag and the CD1a, CD4, HLA-DR lymphoid markers. We have found that the CD68 marker was more frequently positive than the other examined macrophag markers, and proved to be almost as reliable as the recently discovered CD1a. The most interesting result was that the expression of the markers was different in the childhood and adult type of the disease. On the basis of our experience the possibility arise that the phenotype of the childhood and adult type of the Langerhans cell histiocytosis is different.
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PMID:[Expression of macrophage markers in childhood and adult Langerhans histiocytosis (LCH)]. 925 59

Critical to the function of Ag-presenting dendritic cells (DCs) is their capacity to migrate to lymphoid organs and to sites of inflammation. A final stage of development, termed maturation, yields DCs that are strong stimulators of T cell-mediated immunity and is associated with a remodeling of the cell surface that includes a change in the levels of expression of many molecules, including chemokine receptors. We show in this study that CCR3, a chemokine receptor initially discovered on eosinophils, is also expressed by human DCs that differentiate from blood monocytes, DCs that emigrate from skin (epidermal and dermal DCs), and DCs derived from CD34+ hemopoietic precursors in bone marrow, umbilical cord blood, and cytokine-elicited peripheral blood leukapheresis. Unlike other chemokine receptors, such as CCR5 and CCR7, the expression of CCR3 is not dependent on the state of maturation. All DC subsets contain a large intracellular pool of CCR3. The surface expression of CCR3 is not modulated following uptake of particulate substances such as zymosan or latex beads. CCR3 mediates in vitro chemotactic responses to the known ligands, eotaxin and eotaxin-2, because the DC response to these chemokines is inhibited by CCR3-specific mAbs. We postulate that expression of CCR3 may underlie situations where both DCs and eosinophils accumulate in vivo, such as the lesions of patients with Langerhans cell granulomatosis.
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PMID:Expression of a functional eotaxin (CC chemokine ligand 11) receptor CCR3 by human dendritic cells. 1221 6

Langerhans cell histiocytosis (LCH) is a clonal disorder believed to be derivedfrom cells of the dendritic system. Fascin, a 55-kd actin-bundling protein, represents a highly selective marker for dendritic cells of lymphoid tissues and peripheral blood and is involved in the formation of dendritic processes in maturing epidermal Langerhans cells. Since lesional cells of LCH may represent Langerhans cells arrested at an early stage of activation, immunohistochemical expression offascin in epidermal Langerhans cells and in the lesional cells of 34 cases of LCH was evaluated in paraffin sections using an immunoalkaline phosphatase technique. Though epidermal Langerhans cells were nonreactive for fascin, lesional cells in all LCH cases exhibited immunoreactivityforfascin, CD1a, and S-100 protein. Variation in staining intensity was observed in some cases, possibly reflecting differences in cell maturation or activation. Involved tissues included bone, soft tissue, lymph node, thyroid, orbit, and extradural cranial tissue. Immunoreactivity of lesional cells of LCH for fascin supports their derivation from cells of the dendritic system and represents another alteration in the phenotype of Langerhans cells that is associated with maturation, migration, culture, or clonal expansion.
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PMID:Langerhans cell histiocytosis immunohistochemical expression of fascin, a dendritic cell marker. 1221 75

The pathophysiology and pathogenesis of congenital self-healing Langerhans cell histiocytosis (CSHLCH) as well as that of the other types of Langerhans cell histiocytosis is not well understood. Some authors postulate deregulated immunologic mechanisms that result in overproduction of cytokines. We examined a neonate with disseminated papulonodular eruptions containing lymphoid aggregates of B lymphocytes in the chorial layer. The diagnosis of a CSHLCH was made and the follow-up showed a complete involution of the eruptions, leaving atrophic lesions in the sites corresponding to the initial findings. We discuss a possible imbalance of the immune response as a pathogenetic mechanism.
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PMID:Congenital self-healing langerhans cell histiocytosis with atrophic recovery of the skin: clinical correlation of an immunologic phenomenon. 1262 Dec 51

It has been suggested that a switch in chemokine receptor expression underlies Langerhans cell migration from skin to lymphoid tissue. Activated cells are thought to down-regulate CCR6, whose ligand macrophage inflammatory protein-3 alpha (MIP-3 alpha)/CCL20 is expressed in skin, and up-regulate CCR7, whose ligands are in lymphoid tissues. In Langerhans cell histiocytosis (LCH), pathologic Langerhans cells (LCs) accumulate in several tissues, including skin, bone, and lymphoid organs. We have examined 24 LCH cases and find that pathologic LCs expressed CCR6 and CCR7 coincidentally in all cases. Furthermore, MIP-3 alpha/CCL20 is expressed by keratinocytes in involved skin and by macrophages and osteoblasts in involved bone. Expression of CCR6 by pathologic LCs may contribute to their accumulation in nonlymphoid organs such as skin and bone, whereas CCR7 expression may direct them to lymphoid tissue. Histiocytes in Rosai-Dorfman disease and hemophagocytic syndrome also coexpressed CCR6 and CCR7, suggesting that this may be a general attribute of abnormal histiocytes.
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PMID:Coincident expression of the chemokine receptors CCR6 and CCR7 by pathologic Langerhans cells in Langerhans cell histiocytosis. 1264 42

Children with multisystem Langerhans cell histiocytosis (LCH) and risk organ involvement who fail to respond to conventional chemotherapy have an extremely poor prognosis. Myeloablative stem cell transplantation (SCT) as a possible salvage approach for these patients has been associated with a high risk of transplant-related mortality. Therefore, allogeneic stem cell transplantation following a reduced-intensity conditioning regimen (RIC-SCT) has recently been performed as an alternative salvage approach. We report on the experience with allogeneic RIC-SCT in nine pediatric high-risk LCH patients. Conditioning regimen included fludarabine in all patients, melphalan in eight patients, total lymphoid irradiation in six patients, total body irradiation in two, antithymocyte globulin in five, and Campath in four patients. RIC-SCT was well tolerated with regard to common procedure-related complications. Two patients died 50 and 69 days after RIC-SCT, respectively. Seven out of the nine patients survived and showed no signs of disease activity (including one with nonengraftment and full autologous hematopoietic recovery) after median follow-up of 390 days post-SCT. Based on this observation, we conclude that RIC-SCT is a feasible procedure with low transplant-related morbidity and mortality and a promising new salvage approach for high-risk LCH patients with resistant risk organ involvement.
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PMID:Improved outcome of treatment-resistant high-risk Langerhans cell histiocytosis after allogeneic stem cell transplantation with reduced-intensity conditioning. 1593 10

Langerhans cell histiocytosis (LCH) manifesting as a parotid gland mass is an extremely rare clinical presentation. We report a case of LCH involving the bilateral parotid glands in an 81-year-old Japanese female. Pathologically, the lesion was characterized by numerous lymphoid follicles, dense lymphoplasmacytoid infiltrate and cystic dilatation of the parotid gland duct in addition to nodular and diffuse proliferation of LCs. Moreover, both LCs and small T-lymphocytes invaded the ductal epithelium forming a lymphoepithelial lesion-like morphology. The present case indicates that LCHs should be added to the different diagnosis for marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type involving the salivary glands.
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PMID:Incidental Langerhans cell histiocytosis of the parotid gland resembling marginal zone B-cell lymphoma: a case report. 1703 97

Although CD1a+ dendritic cells (DC) in cutaneous T-cell lymphomas (CTCL) have been well documented, the presence of large numbers of DC within lymphoid infiltrates can pose a diagnostic difficulty. We present a case of a 70-year-old man with a 3-year history of recurrent red papules and plaques on the extremities and trunk that was referred to our institution, with the diagnosis of Langerhans cell histiocytosis. Skin biopsies showed a wedge-shaped cellular infiltrate in the superficial and deep dermis consisting of two cell populations. Most prominent were clusters of epithelioid cells with grooved nuclei and abundant eosinophilic cytoplasm, which stained with antibodies to CD1a and S-100. A second, less prominent population of atypical lymphocytes, some with enlarged, hyperchromatic and convoluted nuclei, were intermixed. The latter were positive for CD30, CD3 and CD5 and negative for CD20, CD34, CD68, ALK-1 and TdT. T-cell receptor gene rearrangement studies confirmed a clonal T-cell population, which with the clinical history was consistent with the diagnosis of lymphomatoid papulosis. While previous studies have shown an increased density of dermal DC in CTCL, we believe that this represents the first report of an unusually florid DC proliferation mimicking Langerhans cell histiocytosis and masking a lymphoproliferative disorder.
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PMID:Lymphomatoid papulosis with CD1a+ dendritic cell hyperplasia, mimicking Langerhans cell histiocytosis. 1757 40

The presence of CD 1a+ dendritic cells (DC) has been well described in T-cell lymphoproliferative disorders, and the presence of large numbers of DCs has rarely been reported as a mimicker of Langerhans cell histiocytsis (LCH). We present the case of a 56-year-old female with a solitary nodule on the chin whose case was referred to our institution for confirmation of the diagnosis of LCH. Skin biopsy showed an ulcerated nodule containing a wedge-shaped infiltrate comprised of large atypical cells and cells with prominent grooved nuclei. The constellation of histologic and immunologic features favored a CD30 lymphoproliferative disorder of T-cell lineage even though there were accompanying numerous dendritic histiocytes and CD1a positive Langerhans cells. The sheets of CD30 positive atypical lymphoid cells which express T-cell markers were consistent with CD30 positive lymphoproliferative disease and favor CD30 positive anaplastic large-cell lymphoma (ALCL) over Langerhans histiocytosis. The absence of Anaplastic Lymphoma Kinase (ALK) staining favored a primary cutaneous origin. This case signifies a CD 30+ ALCL of the skin which histopathologically mimics a LCH. Ezra N, Van Dyke GS, Binder SW. CD30 positive anaplastic large-cell lymphoma (ALCL) mimicking Langerhans cell histiocytosis (LCH).
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PMID:CD30 positive anaplastic large-cell lymphoma mimicking Langerhans cell histiocytosis. 1981 47

We present three cases of concurrent Langerhans cell histiocytosis (LCH) and B-lineage lymphoid cell infiltrations and/or nodules in the bone marrow. The first patient was a 25-month-old boy who presented with LCH on the right shoulder and multiple osteolytic lesions. Bone marrow biopsy showed the presence of LCH and two large lymphoid nodules of B-lineage, which were located in the paratrabecular region. Both LCH and the lymphoid nodules resolved after treatment with prednisone, vinblastine, methotrexate, and cyclophosphamide. The second patient was a 7-month-old girl who presented with LCH in the scalp and bone marrow. In spite of the treatment, a follow-up bone marrow analysis performed after 16 months showed LCH and increased B-lineage lymphoid cells in the interstitial area. The third patient was a 26-month-old girl, and imaging studies revealed reddish skin lesions and multiple osteolytic lesions. Skin biopsy and bone marrow biopsy did not show the presence of LCH; however, we initiated the treatment on the basis of the results of imaging studies. The follow-up study after 6 months showed the presence of LCH and large, patchy infiltration of B-lymphoid cells. We report three rare cases of concurrent bone marrow involvement of LCH and B-lineage lymphoid proliferation, which strongly suggest lymphoid malignancy. Further, clonal changes should be studied to elucidate the common pathogenic mechanism between the two diseases.
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PMID:Concurrent langerhans cell histiocytosis and B-lineage lymphoid proliferation in the bone marrow. 1989 48


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