Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Paroxysmal nocturnal hemoglobinuria (PNH) blood cells lack glycosylphosphatidylinositol-anchored membrane proteins such as decay-accelerating factor (DAF) and CD59. This lack is of diagnostic value in PNH. Because reticulocytes in PNH are not yet well characterized, we analyzed reticulocytes obtained from 12 patients with PNH and from 5 healthy volunteers by two-color flow cytometry with a membrane-permeable fluorescent dye, thiazole orange, to identify reticulocytes and monoclonal antibodies to DAF and CD59. Healthy individuals had no affected cells. In all patients, the population of affected reticulocytes negative for DAF and CD59 was markedly higher than the population of affected erythrocytes. Moreover, the population of affected erythrocytes became obviously low in patients who received transfusions and suffered from hemolytic precipitation, whereas the population of affected reticulocytes was unchanged. The persistently high population of affected reticulocytes, despite cytolytic exclusion and an inherently short lifetime, might possibly be explained by relative reticulocytosis caused by an anemia-induced feedback stimulation of erythropoiesis in PNH. Thus, affected reticulocytes could be a reliable marker for the diagnosis of PNH and for the evaluation of erythropoiesis by PNH stem cell.
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PMID:Markedly high population of affected reticulocytes negative for decay-accelerating factor and CD59 in paroxysmal nocturnal hemoglobinuria. 753 94

A 32-year-old man visited Kanto Teishin Hospital complaining of general fatigue in May, 1992. He had been diagnosed as having paroxysmal nocturnal hemoglobinuria since 1980, because of brownish urine in the morning. He received blood transfusion in 1980. In 1983, he was treated with medication. There was no remarkable improvement, however, and he stopped coming to the hospital. When he was admitted to our hospital, hemolytic anemia and hemosiderinuria were noticed. Sucrose hemolysis test and acidified-serum lysis test (Ham test) were both positive. Positive rates of decay accelerating factor and CD59 were 38.8% (control 100%) and 45.4% (control 100%), respectively. His diagnosis was thus confirmed. Bone marrow was slightly hypocellular, and erythroid cells were relatively hyperplastic (M/E ratio 0.68). The oral administration of iron and oxymetholone was not effective for anemia. He was treated with daily subcutaneous administration of recombinant human erythropoietin (EPO, 3,000U/body/day). His hemoglobin level increased from 7.5g/dl to 12.0g/dl in 4 weeks, and general fatigue disappeared. Since he had concurrent chronic hepatitis C, alpha-interferon was also administered and his hemoglobin level is now controlled between 10 and 11g/dl. This case suggests that EPO can be useful for treating hemolytic anemia, even though erythroid cells in the bone marrow are hyperplastic.
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PMID:[Improvement of anemia by recombinant human erythropoietin in paroxysmal nocturnal hemoglobinuria]. 823 Jul 45

Paroxystic nocturnal hemoglobinuria (PNH) is an acquired hemolytic anaemia related to an increase susceptibility of erythrocytes to complement-mediated lysis. PNH is a clonal disease of an hematopoietic stem cell which lost, by mutation, the ability to synthesized phospholipid anchor of membranous proteins, i.e. complement regulatory proteins: DAF, C8BP or CD59. The clinical features of PNH are hemoglobinuria episodes associated with chronic hemolytic anaemia or pancytopenia with active bone marrow or aplastic anaemia. The clinical course is marked by severe thrombotic complications (such as Budd-Chiari syndrome), hemorrhages or infections. The diagnosis is confirmed by in vitro hemolysis tests, and now by facs analysis of cell membrane expression of deficient proteins. Different treatments have been proposed with various results (corticosteroid therapy, androgens, chemotherapy...) but the only way to eliminate the abnormal clone appears to be related bone marrow allograft.
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PMID:[Paroxysmal nocturnal hemoglobinuria]. 823 86

An asymptomatic 26-year-old woman with mild macrocytic anemia (11.6 g Hb/dl) was studied. All biochemical parameters, bone marrow histology and cytogenetics were normal. The Ham's and sucrose tests were negative. A flow cytometric analysis revealed that CD55 and CD59 staining was absent in 20% and 21% of the granulocytes, but erythrocytes and CD34-positive bone marrow cells were CD55 and CD59 positive. Seven months after the initial study, the patient suffered an episode of hemoglobinuria, with mild anemia, moderate thrombocytopenia and a weak positive sucrose lysis test. A new flow cytometric analysis disclosed an increased percentage of CD55 and CD59 negative granulocytes and a 25% of erythrocytes with an intermediate pattern of fluorescence after CD59 labelling. At fourteen months, a population of CD55-deficient erythrocytes was detected and the Ham's test became positive. The present report is, to our knowledge, the first case of smoldering paroxysmal nocturnal hemoglobinuria in a patient with no previous aplastic anemia, or evident pancytopenia. The diagnosis was established by flow cytometry of peripheral blood granulocytes, with apparently phenotipically normal progenitor cells in an early stage of the disease. Flow cytometry appears to be a useful tool in our knowledge of paroxysmal nocturnal hemoglobinuria evolution.
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PMID:De novo smoldering paroxysmal nocturnal hemoglobinuria: a flow cytometric diagnosis. 958 88

Anemia-inducing factor (AIF) was isolated from gastric cancer tissue; however, the human placenta used as the volume of AIF for further analysis did not prove sufficient. This substance was named placental anemia-inducing factor (PAIF). PAIF directly reduces the number of erythrocytes in vitro and reduces the RBC count in rabbits to 80% when i.v. administration of 27 microg/kg of body weight is given. The aim of this study is to better define PAIF and to examine whether the identifical substance expresses on either the surface or in the cytoplasm of established gastric cancer cell lines. PAIF is a glycoprotein with about 20 KD, whose 17 amino acid residues of N terminus were sequenced after Edman treatment. The N-terminus of PAIF were determined as Lqcyncpnptadcktav. This is homologous with that of CD59, which is thought as a regulator of membrane attack complex of complement system. Expression of PAF or CD59 in four established gastric cancer cell lines were examined by indirect immunofluorescence method and by Northern blot hybridization. The cells (1 x 106) were seeded into plastic plates for three days and reacted overnight at 4 degrees C in 0.5 ml of PBS with anti-PAIF polyclonal antibody or with anti CD59 rat monoclonal antibody. Both PAIF and CD59 were stained positively on the surface and/or in the cyroplasm. The total RNAs were prepared from the four kinds of cell lines and normal human lymphocytes. CD59 mRNA was probed in all cell lines by BamH1-EcoR1 fragment of PSRa CD59. The signal levels of MKN-28, MKN-45 and KATO-III were stronger than that of MKN-74, whereas the signal of normal lymphocytes was the lowest. Although there is no decisive evidence that PAIF is exactly the same substance as CD59, and although the biological functions of these two substances are conflictive, and still to be further investigated, the 17 amino acid residues of N-terminus of PAIF expressed in gastric cancer cells were homologous with those of CD59. A derivative of CD59 may exist in gastric cancer.
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PMID:Anemia-inducing factor expressed in gastric cancer is homologous with complement regulatory factor CD59? 989 75

Paroxysmal nocturnal haemoglobinuria (PNH) is an acquired haematological disorder characterized by complement-mediated haemolytic anaemia caused by deficiency of glycosylphosphatidylinositol (GPI) anchored proteins. Somatic mutation of an X-linked gene, PIG-A, is responsible for the defect in biosynthesis of GPI-anchor. It appears that frequency of PNH differs geographically, and seems to be more frequent in some Asian countries, such as Thailand and China. We studied a group of 34 Thai patients with PNH to see whether the somatic mutations in PIG-A, extent of deficiency of GPI-anchored proteins (complete or partial) and complication with aplastic anaemia among Thai patients are different from those in other regions. We determined 37 PIG-A mutations in 33 patients (10 base substitutions, 14 single-base deletions, five multiple-base deletions, three single-base insertions, two multiple base insertions and three others) which were found to be similar to those found in European, American and Japanese patients. Most patients had cells with a complete deficiency of CD59 (type III cells), whereas 19% and 33% of the patients with reliable data for CD59 expression had partially deficient granulocytes and erythrocytes (type II cells), respectively. Most mutations resulted in a complete loss of function of PIG-A in accordance with the prevalent PNH III phenotype. 19 patients (51%) had aplastic anaemia; their PIG-A mutations were not different from those without pre-existing aplastic anaemia. These characteristics of Thai patients are similar to patients from other regions. There was some negative correlation between mean basal Hb concentration and percentage of CD59-negative granulocytes (r = -0. 374; P = 0.0476). In addition, patients with severe anaemia (basal Hb <7 g/dl) had a significantly higher percentage of affected granulocytes than those with mild anaemia (88.5 +/- 9.4 v 64.9 +/- 25.9; P = 0.01). The data suggest that the severity of anaemia in PNH depends partly on the size of the PNH clone.
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PMID:Genotypic, immunophenotypic and clinical features of Thai patients with paroxysmal nocturnal haemoglobinuria. 1023 27

Severe anemia is one of the most lethal complications in children infected with Plasmodium falciparum. The pathogenesis of this anemia is not completely understood. Experimental data from malaria-infected humans and animal models suggest that uninfected red cells have a shortened life span. This study looked for changes in the red cell surfaces of children with severe malarial anemia that could explain this accelerated destruction. A prospective case-control study was conducted of children with severe P falciparum anemia (hemoglobin of 5 g/dL or lower) admitted to a large general hospital in western Kenya. Children with severe anemia were compared with children who had symptoms of uncomplicated malaria and with asymptomatic children. Cytofluorometry was used to quantify in vitro erythrophagocytosis and to measure red cell surface immunoglobulin G (IgG) and the complement regulatory proteins CR1, CD55, and CD59. Red cells from patients with severe anemia were more susceptible to phagocytosis and also showed increased surface IgG and deficiencies in CR1 and CD55 compared with controls. Red cell surface CD59 was elevated in cases of severe anemia compared with asymptomatic controls but not as compared with symptomatic controls. The surface of red cells of children with severe P falciparum anemia is modified by the deposition of IgG and alterations in the levels of complement regulatory proteins. These changes could contribute to the accelerated destruction of red cells in these patients by mechanisms such as phagocytosis or complement-mediated lysis. (Blood. 2000;95:1481-1486)
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PMID:Red cell surface changes and erythrophagocytosis in children with severe plasmodium falciparum anemia. 1066 28

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired stem cell disorder characterized by the deficiency of all proteins anchored to the membrane by the glycosyl-phosphatidylinositol (GPI) anchor. The receptor for urokinase-type plasminogen activator (uPAR) also is attached to the cell membrane by a GPI anchor, and that soluble uPAR (suPAR) is present in plasma. In the present study, we measured uPAR, CD55, and CD59 on granulocytes by means of flow cytometry and suPAR in plasma by means of immunoradiometric assay. The subjects were 20 patients with PNH, 59 other patients with anemia, and 21 healthy individuals. In patients with PNH, both the mean fluorescence intensity and the positive percentage of fluorescence-activated granulocytes of uPAR, CD55, and CD59 were remarkably decreased, whereas in patients with other forms of anemia, except 2 patients with aplastic anemia, the results were not altered in comparison with those for the healthy individuals. The level of uPAR was reduced to the same extent as were those of CD55 and CD59 on the PNH-affected granulocytes. Some peak shape abnormalities (double peaks, peak tailing, or both) in the histogram of fluorescence intensity were also found in patients with PNH. The suPAR concentration of PNH plasma was 4.04+/-2.47 ng/mL, which was higher than that of the healthy individuals, 1.73+/-0.96 ng/mL (P < .01). The positive percentage of fluorescence-activated granulocytes was inversely associated with the plasma suPAR level in patients with PNH (r = -0.79, P < .01). Our data suggest that measurement of uPAR on granulocytes by means of flow cytometry and of suPAR in plasma by means of immunoradiometric assay are specific techniques for the diagnosis of PNH.
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PMID:Diagnostic significance of measurement of the receptor for urokinase-type plasminogen activator on granulocytes and in plasma from patients with paroxysmal nocturnal hemoglobinuria. 1204 78

Severe malarial anaemia is a leading cause of death in African children younger than 3 years of age who are infected with Plasmodium falciparum. The pathogenesis of this anaemia is not understood. The purpose of this study was to determine if P. falciparum induces changes in RBC membranes that contribute to the immune destruction of RBCs. RBCs were collected from healthy subjects and tested using standard haemagglutination assays for 45 antigens representing 21 blood group systems/collections before and after exposure to P. falciparum, strain FVO. Lectins were used to determine whether crypt or neoantigens were expressed on the RBC membrane. Polybrene was used to detect changes in sialic acid. RBCs were cultured in vitro with and without the parasite, and blinded serologic studies were completed. CD35 (complement receptor 1), CD55 (decay-accelerating factor), CD59 (membrane inhibitor of reactive lysis) and CD47 (integrin-associated protein) flow cytometric assays were compared for infected and uninfected RBCs. The percentage of parasitaemia was determined using Giemsa-stained thin blood films. Two (Ch, Lub) of the 45 antigens had differing strengths of agglutination between infected and uninfected RBCs, but these differences were resolved with a second source of antisera. Forty-three antigens showed no significant differences in the strength of agglutination between the infected and uninfected RBCs. Lectin and polybrene testing showed no differences. CD35, CD55, CD59 and CD47 levels showed no significant differences. P. falciparum does not appear to alter the expression of classified immunogenic antigens on the RBC membrane in this in vitro system. The pathogenesis of the haemolytic episode that occurs in these children remains unclear.
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PMID:In vitro RBC exposure to Plasmodium falciparum has no effect on RBC antigen expression. 1207 78

The purpose of the study is to establish a colorimetric method of HEC toxin hemolysis test for diagnosis of paroxysmal nocturnal hemoglobinuria (PNH). RBCs from normal persons and patients with PNH and non-PNH anemia were treated with HEC toxin secreted by Aeromonas hydrophila J-1 strain and the absorbance at 630 nm was measured to quantitate the extent of hemolysis. The results demonstrated that the RBCs from PNH patients showed resistance to the toxin hemolysis, which was in accord with the percentages of CD59(-) cells, while the RBCs from normal persons and non-PNH anemic patients were nearly totally lysed. It is concluded that the method can be considered as a simple, specific and reliable method for the diagnosis of PNH.
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PMID:[A colorimetric method of HEC toxin hemolysis test for diagnosis of paroxysmal nocturnal hemoglobinuria]. 1251 27


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