Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Natural killer cell activity (Nka) of peripheral blood mononuclear cells (PBMCs) against K562 cell targets was assessed in 66 patients with chronic idiopathic neutropenia of adults (CINA) using the 16-h 51Cr-release assay. It was found that CINA patients exhibited significantly lower Nkr than normal subjects, which strongly correlated with the degree of neutropenia and the numbers of circulating neutrophils. Patients' NKa was increased by recombinant human interleukin-2 (rhIL-2) or recombinant human interferon-alpha (rhIFN-alpha), but the values obtained did not reach the respective NKa values found in normals. However, percentages of cytokine-induced rises of NKa did not differ statistically between patients and normal subjects. No serum inhibitors of NKa were demonstrated in our patients. CINA patients had low numbers of circulating NK cells as defined by the expression of NK-cell-related surface markers CD16, CD56, and CD57. CD16+ and CD56+, but not CD57+, cells correlated with the values of baseline NKa. The numbers of all these cell subsets correlated with the degree of neutropenia and the numbers of circulating neutrophils. Using CD56+-enriched PBL suspensions, it was shown that patients' NK cells displayed normal tumor cell binding capacity and produced in vitro normal amounts of natural killer cytotoxic factor(s) against K562 cell targets upon activation with rhIFN-alpha. Finally, percentages of perforin-expressing and granzyme B-expressing CD16+ cells did not differ statistically between patients and normal controls. Based on all these observations, we concluded that CINA patients display low NKa probably because they have low numbers of circulating NK cells. No functional abnormalities of NK cells were demonstrated. The cause and the underlying mechanisms leading to NK-cell depletion in these patients remain to be clarified.
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PMID:Defective natural killer cell activity of peripheral blood lymphocytes correlates with the degree of neutropenia in patients with chronic idiopathic neutropenia of adults. 961 29

The initiation of hemodialysis using cuprophane membranes is followed by a rapid fall in the circulating neutrophil count. This neutropenia is caused by a transient sequestration of neutrophils in the lung due to homotypic aggregation, largely in response to generation of C5a by contact of plasma with the dialyzer. The transient nature of hemodialysis neutropenia is due to desensitization of neutrophils to stimulation by C5a, thus demonstrating desensitization in vivo. To examine the in vivo effects on surface phenotype of continuous exposure of neutrophils to C5a over 3 h, the surface expression of 22 antigens was examined by flow cytometry in patients undergoing dialysis. Neutropenia was prominent at 15 min and absent at 60 and 180 min of dialysis. CD10, CD11b, CD11c, CD13, CD18, CD35, CD45, CD66acde, and CD66b were upregulated at 15 min and remained upregulated at 180 min. CD61 and CD63 increased slightly at 15 min and returned to baseline by 180 min. CD16 and CD62L were down regulated at 15 min and normalized by 180 min. CD15s, CDw17, CD32, and CD44 were slightly down regulated at 15 min and then returned to baseline by 180 min. CD11a, CD15, CD24, CD31, and CDw65 did not change during dialysis. This study demonstrates the changes in surface phenotype of neutrophils during prolonged in vivo exposure to C5a over 3 h, during which time neutrophils become desensitized to subsequent stimulation by similar concentrations of C5a but maintain responsiveness to other chemotactic stimuli.
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PMID:Changes in neutrophil surface phenotype during hemodialysis. 982 71

Allogeneic haematopoietic stem cell transplants might induce immunological alterations leading to autoimmune-like syndromes. In particular neutrophil-associated antigens could represent the target for autoantibodies against neutrophils in patients receiving an allogeneic peripheral stem cell or bone marrow transplantation, giving rise to granulocytopenia. With this aim we studied prospectively 43 allotransplanted patients for the presence of antibodies reacting with neutrophils (ARN), looking for a correlation with a post-engraftment neutropenia. Our data showed that the direct test for ARN was positive in 30 patients. Interestingly, 7/7 patients who received a T-cell-depleted marrow transplant developed ARN. Antibodies with a specific neutrophil-antigen reactivity were detected in 4 patients, 1 with an anti-CD16/FcbetaRIIIb receptor reactivity and 3 with anti-NA 1 reacting patterns, respectively. From a clinical point of view, it was not possible to demonstrate a close and significant relationship between neutropenia and ARN, although patients showing ARN had slightly lower absolute levels of peripheral neutrophils until 6 months after BMT. In conclusion, ARN may be detected in the majority of patients following allogeneic stem cell transplantation; in addition, since ex vivo or in vivo T-cell-depletion leads to a higher percentage of patients positive for ARN, it could be hypothesized that "autoimmune-like" disorders in transplanted patients might be related to a T-cell derangement due to different numbers and subsets of T lymphocytes.
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PMID:Antibodies reactive with neutrophils following allogeneic haematopoietic stem cell transplantation. 991 13

Chronic natural killer cell lymphocytosis is a persistent state of natural killer (NK) cell (CD3-CD16/CD56+) excess in the peripheral blood that is not associated with clinical lymphoma. In 16 consecutive patients (median age 60.5 years, range 7-77), males were overrepresented (M:F 7:1) and the median absolute NK cell count was 4.09 x 10(9)/l (range 1.2-16.6). Bone marrow examination was performed in 14 patients and showed atypical granulomata in two; chromosome studies in seven patients were normal. Clonal T-cell receptor gene rearrangement was not found in any of 12 patients evaluated. At presentation, seven patients (44%) had no clinical symptoms or signs and the others had vasculitic skin lesions (three patients), non-neutropenic fever (three patients), recurrent neutropenic infection (two patients), musculoskeletal symptoms (two patients), peripheral neuropathy (two patients), aphthous ulcers (one patient), and splenomegaly (one patient). Five patients had anaemia, five had neutropenia, and two had thrombocytopenia. After a median follow-up of 5.1 years (range 0-10.2) from immunophenotypic diagnosis or 5.7 years (range 0.1-14.1) from documentation of absolute lymphocytosis, vasculitic glomerulonephritis developed in one patient, accelerated splenomegaly developed in a patient receiving myeloid growth factor treatment, and severe aplastic anaemia developed in one patient. Treatment with nonsteroidal anti-inflammatory drugs or immunosuppressive agents was variably successful.
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PMID:A long-term study of patients with chronic natural killer cell lymphocytosis. 1051 98

Chronic natural killer (NK) lymphocytosis involves a persistent increase in CD56+ large granular lymphocytes (LGLs) that is sometimes associated with immune-mediated complications, such as anemia and neutropenia. However, aplastic anemia (AA) is a rare complication. Here we describe 2 patients with severe AA who presented with persistent increases in NK cells. Their LGLs were positive for CD56, CD16, and intracellular interferon (IFN)-gamma but negative for CD3, Fas-ligand, and T-cell receptor rearrangement, findings that are compatible with NK cells. Not only the number of NK cells, but NK activity as well, was increased in both patients. The number of NK cells changed according to hematologic recovery and relapse in 1 case. Thus, there seemed to be a close relationship between NK cells and the progression of AA, at least in this instance. Further investigation of the clinical course of similar cases and the characteristics of NK cells is necessary.
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PMID:Severe aplastic anemia associated with chronic natural killer cell lymphocytosis. 1119 12

Antibodies directed against antigens on the granulocyte (neutrophil) membrane can cause a variety of disorders including neonatal immune neutropenia, immune neutropenia after bone marrow transplantation, autoimmune neutropenia, and drug-induced immune neutropenia. Since granulocyte alloantibodies can lead to severe pulmonary transfusion reactions (TRALI), febrile transfusion reactions and refractoriness to granulocyte transfusions, they also play an important part in blood transfusion. The implicated human neutrophil alloantigens (HNA) have been renamed in the recently introduced HNA nomenclature which is based on the antigen's glycoprotein location. The Fc gamma Receptor IIIb (CD16, HNA-1) and the NB1 glycoprotein (CD177, HNA-2) represent the major immunogenic molecules of the neutrophil membrane. They bear the clinically most important antigens HNA-1a,-1b,-1c (NA1, NA2, SH) and HNA-2a (NB1), respectively. For the detection of granulocyte antibodies, a combination of immunofluorescence and agglutination tests together with a panel of freshly isolated, typed test neutrophils has been shown to represent the best means of detection. The introduction of the glycoprotein-specific assay "MAIGA" has improved alloantibody identification considerably. To facilitate and improve neutrophil typing, PCR-SSP techniques have been established for HNA-1a,-1b, and -1c genotyping.
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PMID:Granulocyte immunology. 1173 15

Primary auto-immune neutropenia (AIN) is usually described in children. Secondary AIN occurs in collagen vascular diseases such as rheumatoid arthritis and (Felty's syndrome), Gougerot-Sjogren syndrome, and systemic lupus erythematosus. Some cases of other immune cytopenia (idiopathic thrombocytopenic purpura, Evans's syndrome) or lymphoproliferative disorders (large granular lymphocyte leukemia, malignant lymphoma) may be associated with AIN. Some cases of primary AIN occur, especially in children. The diagnosis of AIN depends on the demonstration of autoantibodies directed against neutrophil-specific antigens like CD16. The availability of granulocyte-colony stimulating factor for the treatment of AIN has been a major advance. In some cases, immunosuppressive therapy using prednisone, methotrexate, cyclosporine A must be added, especially in cases of secondary AIN.
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PMID:[Autoimmune neutropenias]. 1175 71

Antibodies to neutrophil antigens can cause neonatal alloimmune neutropenia, autoimmune neutropenia, febrile transfusion reactions, and transfusion-related acute lung injury. Several neutrophil antigen systems have been described serologically, but only the human neutrophil antigen-1 (HNA-1) or NA and HNA-2 or NB systems have been well characterized biochemically and molecularly. HNA-1 antigens are located on FcgammaRIIIb, CD16. HNA-2 antigens are located on 58- to 64-Kd glycoprotein, CD177, and are encoded by a gene on chromosome 19 that belongs to the Ly-6 family. The function of the CD177 is not known, but the CD177 gene is highly homologous to a gene overexpressed in neutrophils from patients with polycythemia rubra vera called PRV-1. New polymorphisms in these antigen systems are still being described, but the complete understanding of these neutrophil antigen systems has been slow because of the complexity of these genes.
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PMID:Neutrophil alloantigens. 1178 31

There have been few reports of large granular lymphocyte (LGL) leukemia with neutropenia complicated with pure red cell aplasia (PRCA) that developed after human parvovirus (HPV) B19 infection. We report here the case of a 35-year-old female who developed HPV B19-associated PRCA with T-LGL leukemia. LGL count of peripheral blood was lower than 2 x 10(9) l(-1), although phenotypic analysis of LGL showed CD3+, CD16-, CD56-, CD57+ with double positive for CD3 and CD57, and genetic study showed the clonal rearrangement of T-cell receptor gene. Microscopically, the patient's bone marrow showed characteristic giant proerythroblasts. A serologic study of HPV B19 was positive for IgM, but negative for IgG, with a positive result on Dot-blot hybridization assay for HPV B19 DNA. Severe anemia and reticulocytopenia ameliorated without treatment 10 days after the initial examination, but slight anemia, neutropenia, a moderate increase of LGL counts with rearrangement of TCR gene, and positive result of HPV B19 DNA has persisted 7 months after the initial examination. We suggest that this viral infection may play an etiologic role in some patients with LGL leukemia who develop PRCA.
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PMID:Pure red cell aplasia associated with parvovirus B19 infection in T-large granular lymphocyte leukemia. 1191 33

A 52-year-old woman presented to our clinic for investigation of agranulocytosis and mild lymphocytosis. A diagnosis of T-large granular lymphocyte leukemia was made, based on immunophenotyping findings of the peripheral blood lymphocytes (CD3, CD8, CD16, CD57). Flow cytometric analysis of TCR-Vbeta repertoire showed single Vbeta9 expression on peripheral T-cells. Clonality was also demonstrated with PCR analysis which revealed clonal rearrangement of TCRgamma-chain gene. Granulocyte-macrophage colony-stimulating factor (G-CSF) (G-CSF), cyclosporine, methylprednisolone and oral methotrexate failed to correct the neutropenia. Finally, treatment with 2-deoxycoformycin (DCF) was successful and resulted in complete correction of the neutrophil count. Flow cytometric analysis of TCR-Vbeta repertoire proved to be an effective method to assess the therapeutic response to various treatments and to evaluate residual disease.
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PMID:2-deoxycoformycin in the treatment of T-large granular lymphocyte leukemia. 1280 46


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