Langerhans cell histiocytosis (LCH) is a rare disorder characterized by an abnormal accumulation and/or proliferation of cells with a Langerhans cell phenotype. Although no clear cause of LCH has been identified, it has been postulated that LCH might be the consequence of an immune dysregulation, causing Langerhans cells to migrate to and accumulate at various sites. Production of cytokines and...

Distribution of B lymphocytes, T lymphocytes subpopulations, activated T lymphocytes and Langerhans cells of the nasal mucosa in 28 patients with nasal allergy ranging in age from 19 years to 54 years was studied. The specimens from inferior turbinates were frozen at -70 degrees C and sliced at a thickness of 4 microns by cryostat. Monoclonal antibodies and peroxidase-antiperoxidase staining (O...

Bone marrow-derived leukocytes of murine epidermis can express two phenotypes: typical Langerhans cells, which are Ia+ and Thy-1-, and a recently discovered second population that is Thy-1+ and Ia-. To verify that these phenotypes are expressed by two different cell types, and to help understand their lineage and function, we have studied morphology and reactivity with a large panel of antibodi...

Eph receptor tyrosine kinases and their ligands, the ephrins, have been primarily described in the nervous system for their roles in axon guidance, development, and cell intermingling. Here we address whether Eph receptors may also regulate dendritic cell (DC) trafficking. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that DCs derived from CD34+ progenitors, but not f...

Langerhans cell histiocytosis (LCH) is a heterogeneous group of diseases characterized by a pathological proliferation of cells phenotypically similar to Langerhans cells. The disease course is variable, alternating between resolving and potentially fatal forms. The diagnosis is based on clinical appearance and confirmed by CD1a positivity and / or immunohistochemistry. We report the case of a ...

Pulmonary Langerhans cell histiocytosis (PLCH) is a rare interstitial lung disease seen as part of multisystem Langerhans cell histiocytosis, or as an isolated form of the disease. The majority of cases of the latter are seen in adults and associated with cigarette smoking, which probably plays a central etiologic role. Although the mechanisms leading to the development of isolated PLCH are unc...

BACKGROUND Langerhans cell histiocytosis is a sporadic disease caused by an uncontrolled pathogenic clonal proliferation of dendritic cells that have Langerhans cell characteristics. New treatment protocols provided by the HISTSOC-LCH-III (NCT00276757) trial show an improvement in the survival of children with langerhans cell histiocytosis. CASE PRESENTATION We report a case of Langerhans cel...

Langerhans cell histiocytosis following T-ALL: clonally related neoplasms with persistent expression of constitutively active NOTCH1. Am J Hematol. 2008;83(2): 116-121. 7. Coury F, Annels N, Rivollier A, et al. Langerhans cell histiocytosis reveals a new IL-17A-dependent pathway of dendritic cell fusion. Nat Med. 2008;14(1):81-87. 8. Allen CE, McClain KL. Interleukin-17A is not expressed by CD2...

BACKGROUND Systemic non-Langerhans cell histiocytoses are disorders characterized by the accumulation of histiocytes that do not meet the criteria for Langerhans cells in various organs. So far, no causative treatment is known. OBSERVATIONS Herein, we report the case of a 41-year-old man with Rosai-Dorfman disease, a form of systemic non-Langerhans cell histiocytoses, with histiocytic infiltr...

Immunohistochemistry was used to identify, enumerate, and describe the tissue distribution of Langerhans type (CD1a and CD207), myeloid (CD1c and CD141), and plasmacytoid (CD303 and CD304) dendritic cell subsets in oral mucosa of allergic and non-allergic individuals. Allergic individuals have more CD141+ myeloid cells in epithelium and more CD1a+ Langerhans cells in the lamina propria compared...