Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019621 (Langerhans cell histiocytosis)
 3,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sera from 120 children and young adults with acute leukaemia (59), various other tumours (53) and histiocytosis X (eight) were studied for the presence and characteristics of circulating immune complexes (CIC). Serial and parallel testing was performed using: C1q binding (solid phase), Raji cell radioimmunoassay and anti-C3 (solid phase). CIC were detected in 36 of 56 (64%) patients with acute lymphoblastic leukaemia (ALL) and in 62% of other tumour subjects. In the ALL sera, the mean positive C1q binding was 5.4 s.d., Raji cell 4.2 s.d. and anti-C3 4.4 s.d. In 12 ALL sera CIC were characterized for molecular size by sucrose gradient centrifugation. Most samples showed high molecular weight (19S) complexes but intermediate (11-14S) and smaller (8-9S) complexes were also detected. There was no apparent relationship between the presence, amount or physical size of the detectable CICs and clinical course of the patients studied; 12 patients with ALL in long term remission showed presence of CIC at some time during their course. Immune complexes precipitated from leukaemic sera were also examined for the presence of common ALL antigen (cALL) and Ia(DR) antigens utilizing rabbit antisera and mouse monoclonal antibodies. Experiments with isolated immune complexes from ALL sera provided no positive evidence for the presence of cALL antigen or Ia antigen within immune complex materials from ALL patients.
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PMID:Characterization of immune complexes in acute lymphoblastic leukaemia. 660 8

Langerhans cell histiocytosis (LCH), also known as histiocytosis X, is a rare human disorder characterized by an abnormal accumulation and/or clonal proliferation of Langerhans cells (LCs) in various body organs. The cellular origin of LCs has been a subject of considerable debate since their discovery. As specialized dendritic cells strategically located in epithelia, LCs are generally considered to be of myeloid origin from the bone marrow, however, recent studies in mice have shown that LCs can be derived from lymphoid-committed CD4 precursors, suggesting a lymphoid origin. In human LCH, concomitant or sequential occurrence of a lymphoid or myeloid malignancy has been occasionally reported, suggesting the presence of lineage plasticity and/or the possibility of transdifferentiation of 2 otherwise morphologically and immunophenotypically different neoplasms. To gain a better understanding of the pathogenesis and cellular origin of human LCH, we retrospectively investigated 46 well-characterized LCH cases to detect clonal rearrangements of T-cell receptor gamma gene (TRG@) and immunoglobulin heavy chain and kappa light chain genes (IGH@/IGK@). The study included 25 males and 21 females, with ages ranging from <1 to 59 years. None (0/46) of the cases had a known history or concurrent B or T-cell lymphoma. Of 46 cases, 30% (14/46) cases had clonal IGH@ (4 cases), IGK@ (5 cases) or TRG@ (9 cases) gene rearrangements, respectively. Interestingly, of the 14 cases with at least one clonal rearrangement of lymphoid receptor genes, 3 LCH cases were shown to have both TRG@ and IGH@/IGK@ gene rearrangements, but failed to express T-cell or B-cell lineage specific or associated markers, suggesting lineage plasticity or infidelity of the neoplasm. Furthermore, all of the 14 cases were negative for t(14;18) by quantitative PCR analysis. In conclusion, our study shows that lymphoid receptor gene rearrangements can be detected in a subset of sporadic LCH cases, suggesting a possible lineage relationship between LCs and lymphoid cells or alternatively, derivation of LCs from lymphoid/myeloid precursors. The results provide genotypic evidence supporting the current notion of lineage plasticity of hematopoietic cells and their associated neoplasms.
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PMID:Detection of clonal lymphoid receptor gene rearrangements in langerhans cell histiocytosis. 2055 22