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

We report a case of transient neonatal neutropenia due to a maternal iso-immunization against a non polymorphic region of the glycosylphosphatidylinositol-linked Fc receptor type III (CD16) on granulocytes. The mother's granulocytes were typed NA1-negative, NA2-negative and CD16-negative with human and monoclonal antibodies whereas her lymphocytes express the CD16 molecule. Expression of other markers were comparable to the controls. Flow cytometric analysis showed that maternal antibody recognized the granulocytes but not the lymphocytes from blood bank donors and that its binding was decreased on normal, phospholipase C-treated, granulocytes. The binding of commercial CD16 monoclonal antibodies was also dramatically decreased on normal granulocytes pre-incubated with maternal serum. The CD16 specificity of the antibody was confirmed by negative reactions with another CD16-deficient granulocytes. This observation leads us to conclude that cell-lineage specific differences of CD16 molecules are recognized by the patient's antibody. Moreover, we confirm that the absence of the FcRIII (CD16) on granulocytes is not associated with any pathology or susceptibility to infections and that, in the children, the blockade of this receptor by the maternal antibody only led to moderate neutropenia.
 ...
PMID:Iso-immune neonatal neutropenia due to an anti-Fc receptor III (CD16) antibody. 138 83

The chemiluminescent (CL) response of interferon-gamma-treated U937 (IFN-U937) cells to sensitized target cells has been used to detect red cell, platelet and granulocyte antibodies. A clone of U937 cells was selected which expressed Fc receptor I (Fc gamma RI) and which, after incubation with IFN-gamma for 72 h, was capable of generating high levels of lucigenin-enhanced CL. The CL responses of IFN-U937 cells and peripheral blood human monocytes to sensitized red cells, platelets or granulocytes were then compared. Assays using monocytes or IFN-U937 cells were of comparable sensitivity for detection of antibodies against all three types of target cell. In addition, the use of IFN-U937 cells reduced interassay variation and simplified assay performance. The potential clinical usefulness of these CL assays was suggested by the ability of both monocytes and IFN-U937 cells to respond to red cells, platelets or granulocytes sensitized with sera from pregnant women whose babies had either haemolytic disease of the newborn (HDN), alloimmune thrombocytopenia or alloimmune neutropenia respectively. In addition, monocytes and IFN-U937 cells both responded to red cells sensitized with antibodies against a variety of specificities of assumed (although not documented) clinical significance for blood transfusion recipients. In contrast, monocytes and IFN-U937 cells responded only weakly to red cells sensitized with either anti-D in sera from mothers of babies unaffected by HDN, or with antisera containing high titre antibodies with specificities not normally associated with significantly reduced red cell survival.
 ...
PMID:The use of interferon-gamma-treated U937 cells in chemiluminescence assays to detect red cell, platelet and granulocyte antibodies of potential clinical significance. 147 11

Haemodialysis neutropenia and impaired granulocyte function are transitory, but the consequences of altered granulocyte function are observed at the end of haemodialysis. Activity of polymorphonuclear receptor for Fc and C3 complement component, circulating immune complexes and components of complement (C1 inactivator, C4, C3, C3 proactivator) were measured in ten patients before and at the end of haemodialysis. Significant decrease in polymorphonuclear Fc receptor activity (1689 cells/mm3 before and 1277 cells/mm3 after HD) and increase of circulating immune complexes (69.9 micrograms/dl before and 112.7 micrograms/dl after HD) were observed at the end of haemodialysis. A decrease in complement C3 component was observed after haemodialysis (866 mg/l before and 804 mg/l after HD); the other components: C1 inactivator, C4 component, and C3 proactivator, remained unchanged. Increase of circulating immune complexes and decrease of Fc receptor activity correlated with a decrease in phagocytic function of polymorphonuclear leukocytes.
 ...
PMID:Phagocytic function of neutrophils during dialysis in relation to some immunological findings. 177 64

In 1981, Imbach et al. (Lancet, 1, 1228-1231) reported that infusion of intravenous immunoglobulin (IVIG) would substantially elevate platelet counts in children with acute or chronic idiopathic thrombocytopenic purpura (ITP). Subsequent studies confirmed these findings and extended the effect to adults and to newborns with passive immune thrombocytopenia. Studies in children with acute ITP demonstrated that administration of IVIG was the fastest way to increase a patient's platelet count, and that this agent could be given at doses as high as 1 g/kg/day so that the course of therapy and response to treatment would be more rapid. Reports of effective treatment of patients with autoimmune neutropenia and autoimmune hemolytic anemia by IVIG broadened the scope of its usefulness. In addition, several studies in children and adults with chronic ITP suggested that repeated infusions were a safe and effective way to maintain an adequate platelet count in such patients, and might also gradually lead to lasting improvement. These studies and Imbach's controlled trial in children with acute ITP suggested that IVIG therapy might provide a curative effect in addition to the acute effect. To combine all of these clinical effects with a multitude of in vitro observations to explain the mechanism of action of IVIG is complicated. Fehr et al. (N. Engl. J. Med. 306, 1254-1258, 1982) showed that Fc receptor blockade occurs following administration of IVIG. This effect is clearly demonstrated in vivo by the delayed removal from the vascular space of antibody-coated red blood cells following infusion of IVIG. In addition, many less well-defined effects occur in relation to immunoglobulin production, induction of suppressor cells, antiplatelet antibody levels, and bone marrow platelet production. Studies continue to try to define which effects actually underlie the clinical effects seen, and which are merely test-tube phenomena.
 ...
PMID:The use of intravenous gamma-globulin in idiopathic thrombocytopenic purpura. 247 85

Lymphocytes, co-expressing CD4/Leu7 and CD8/Leu7 markers respectively, taken from two patients having large granular lymphocytosis taking an indolent clinical course have been comparatively studied for function as NK cells and T cells. Both large granular lymphocytes (LGLs) were acid phosphatase positive and showed a beta-glucuronidase reaction in their cytoplasmic granules. Studies on case 1 indicated that the CD4/Leu7 lymphocytosis with LGL morphology takes a benign clinical course with mild neutropenia as well as those of CD8/Leu7 LG lymphocytosis. Both CD4/Leu7 and CD8/Leu7 LGLs behave similarly in their lack of NK activity, and manifest decreased IL-2 production in vitro and show a low IL-2 receptor expression unrelated to their T cell phenotype, but behave differently in influencing the immunoglobulin production in vitro and the ADCC activity, depending on their T cell phenotype and on the expression of Fc receptor, respectively. Furthermore, the altered Fc receptors which were undetectable by the Leul 1 antibody but were still effective for ADCC activity might be present in case 2 LGLs.
 ...
PMID:CD4/Leu7 and CD8/Leu7 large granular lymphocytosis: comparative studies between NK cells and T cells. 251 16

Intravenous immunoglobulin (IVIG) may be considered first-line maintenance therapy for idiopathic thrombocytopenic purpura (ITP) because it has been proven to be the least toxic. In a study of 25 children with acute ITP, treatment with IVIG maintained platelet counts above 40,000/mm3 in all of the children. After 1 year, none of these patients required further therapy. In another study group of 25 pediatric patients with chronic ITP, treatment with IVIG circumvented splenectomy in 60% of the cases. The therapeutic regimens for adults and children are described, as is a strategy to overcome IVIG resistance. Experience with IVIG in hemolytic anemia and neutropenia are discussed. The mechanism of action is explored in some detail, specifically as it relates to reticuloendothelial system (RES) Fc receptor blockade and suppression of antiplatelet antibody synthesis.
 ...
PMID:Therapy in cytopenia. 376 52

Intravenous gammaglobulin (IVIgG) was used to treat autoimmune neutropenia of infancy in two males with repeated infections. The neutrophil count increased significantly in both patients with the initial IVIgG therapy; 1 patient went into remission. The neutrophil count in the other remained above baseline for 3 wk, and a subsequent booster infusion also caused the neutrophil count to increase. The patients have remained clinically well since their treatment began. Serial studies of antineutrophil antibody and serum lysozyme, performed to elucidate the mechanism of action, suggested decreased neutrophil destruction, perhaps by Fc receptor blockade, as well as decreased synthesis of antineutrophil antibody. Neutrophil function was not impaired after the neutrophil count increased. Many patients with immune neutropenia have a benign course, but those who have significant infections could be treated, acutely or prophylactically, with intravenous gammaglobulin.
 ...
PMID:Reversal of neutropenia with intravenous gammaglobulin in autoimmune neutropenia of infancy. 619

A patient with long standing seropositive rheumatoid arthritis developed lymphocytosis which phenotypically involved the cytotoxic/suppressor T-lymphocyte population. There are 10 reported instances of this new disease entity described as "chronic T-cell lymphocytosis with neutropenia" or "chronic suppressor T-cell lymphocytic leukemia." The disease is characterized by hepatosplenomegaly, neutropenia, and the frequent presence of rheumatoid factor without clinical evidence of rheumatoid arthritis. Splenectomy in our patient, as well as in other instances where undertaken, has been ineffective in alleviating the neutropenia. The peripheral blood lymphocytes in our patient were OKT-3+, OKT-5+, OKT-8+, OKT-11+, cALL-, OKT-6-, TdT-. They possessed ADCC but no NK activity and did not suppress PWM-induced B-cell differentiation in spite of the presence of Fc receptor for IgG. Since the lymphocytosis of OKT-8+ cells appears to be clonal, it is suggested that the disease be designated chronic suppressor T-cell lymphocytic leukemia.
 ...
PMID:T-suppressor cell chronic lymphocytic leukemia. Phenotypic characterization by monoclonal antibodies. 623 99

A 52-year-old Caucasian man with chronic neutropenia and recurrent infections was found to have an increased proportion of peripheral T lymphocytes having Fc receptors for IgG (T gamma ). Although levels of antibody-dependent cell-mediated cytotoxicity (ADCC) and "natural" killing (NK) by unfractionated lymphocytes were similar to those of a control donor, the frequency of KN cells was markedly increased. Removal of E rosette-forming cells eliminated both NK and ADCC by the patient's peripheral blood, in marked contrast to the enhanced cytotoxicity seen with control lymphocytes. Both normal and patient ADCC and NK functions were removed by depletion of Fc receptor-bearing cells. These depletion experiments proved that all of the patient's killer cells were E rosette-forming T gamma cells, in contrast to the heterogeneous pattern of null gamma and T gamma killer cells seen in the blood of normal donors. The homogeneity of the T gamma proliferation suggested that ADCC and NK were mediated by the same cell type, albeit acting by different mechanisms. The addition of the patient's serum and lymphocytes to chromium-labelled normal granulocytes caused a low but significant level of cytotoxicity, indicating that the patient's neutropenia may have been caused by a similar mechanism in vivo. There was no evidence of complement-dependent serum antibody-mediated neutrophil lysis, but one serum sample taken over the course of the patient's disease agglutinated granulocytes from four of five donors tested.
 ...
PMID:Studies of human natural killer cells. III. Neutropenia associated with unusual characteristics of antibody-dependent and natural killer cell-mediated cytotoxicity. 697 46

Three children (girls) suffered from neutropenia mediated by anti-neutrophil IgG-Fc receptor type III (Fc gamma RIII) antibodies. The first patient (newborn) had asymptomatic and transient neutropenia caused by maternal Fc gamma RIII iso-antibodies. The second patient (6 months), whose neutropenia was diagnosed as a 'benign neutropenia of childhood' caused by transient anti-NAI autoantibodies, suffered from mild bacterial infections. The third patient (12 years) suffered from serious infections. The anti-Fc gamma RIII autoantibodies showed neither anti-NA1 nor anti-NA2 specificity. She also developed autoimmune thyroiditis (Graves' disease). Both the duration of the neutropenia and the seriousness of the bacterial infection were variable in our patient group. The first two patients both made spontaneous recoveries, while the third patient depended ultimately on granulocyte-colony stimulating factor (G-CSF).
 ...
PMID:[Neutropenia due to antibodies against Type III Fc receptors on neutrophil granulocytes: 3 children with different clinical courses]. 956 43


1 2 Next >>