Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The case is described of an 8-years-old girl with consanguineous parents. She was apparently well, apart, from growth retardation, until 18 months of age when she developed severe normocytic hypochromic anaemia. Bone marrow examination revealed vacuolisation of the erythroid and myeloid precursor, and electron microscopic studies showed striking sideroblastosis with ringed arrangement of the iron granules. Porphyrin metabolism was apparently normal, whereas blood levels of iron and ferritin were high. A careful study of the exocrine pancreas showed completely normal function. Vitamin B6 administration was unsuccessful. The patient is transfusion-dependent, and iron chelation treatment has produced good results. The case could be a new entity or a variant of congenital sideroblastic anaemia, since it has some features in common with the syndrome described by Pearson et al.
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PMID:Congenital refractory anaemia with vacuolisation of bone marrow precursors, sideroblastosis and growth failure in a girl with normal endocrine pancreatic function. 269 75

Ferritin H and L subunits present cell-specific features of structure, function, and transcriptional regulation. Mouse Friend erythroleukemia cells offer an interesting model to analyze the erythroid-specific expression of ferritin genes for comparison with the liver, an iron-storing tissue. cDNA clones for mouse ferritin H and L subunits have been isolated and sequenced. The two subunits have very similar calculated masses, 20.9 and 20.6 kDa for H and L, respectively. Electrophoretic analysis of the subunits encoded by the cDNA 1) allows unambiguous identification of mouse ferritin subunits; 2) clearly shows that mouse H and L chains can make heteropolymers in vitro; and 3) demonstrates that, at least in vitro, free subunits can coexist with subunits polymerized into complete shells. The mouse ferritin gene family displays a variable degree of complexity, ranging from three homologous sequences for the H genes to 10-14 homologous loci for the L genes. Transcription of ferritin genes exhibits tissue-specific difference. Nuclear transcriptional run-off experiments show that the L gene is more actively transcribed in the liver than in Friend erythroleukemia cells at different stages of maturation. The accumulation of the H subunit mRNA which results from dimethyl sulfoxide induction of Friend cells is the consequence of an increase in the transcription rate of the H gene. However, the H gene mRNA is transcribed at a similar rate in the liver and in induced Friend cells although 5-fold more mRNA accumulates in these cells. Therefore, there is a tissue-specific regulation of mouse ferritin expression at both the transcription and mRNA stability levels.
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PMID:Transcriptional regulation of ferritin H and L subunits in adult erythroid and liver cells from the mouse. Unambiguous identification of mouse ferritin subunits and in vitro formation of the ferritin shells. 270 74

In order to reveal the pathway of iron release from macrophages, a 59Fe-labelled ferric hydroxide-potassium polyvinyl sulfate complex (Fe-PVS) was injected intravenously into anemic rats and the level of radioactivity in the liver, spleen, bone marrow, blood plasma and red blood cells (RBC) was estimated at various time intervals after the injection. Histochemical observation of ferric iron and ferritin in the liver was also made on anemic rats treated using unlabelled Fe-PVS. Fe-PVS injection promoted the recovery of anemia causing a rapid increase in the RBC number, with activated erythropoiesis occurring in the spleen and bone marrow. Soon after the injection, most of the radio iron was found in the liver with a small amount in the circulating erythrocytes, bone marrow and spleen. The iron level in the liver decreased gradually with a rapid increase in the iron level of the erythrocytes which reached a very high level 6 days after the 59Fe-PVS injection. Histochemical observations showed a heavy deposition of ferritin in the Kupffer cells 3 days after Fe-PVS injection. This deposition was minimized after 6 days with an increase in the level of ferritin in the parenchymal cells in the central area of acini. The level of radioferritin estimated biochemically in the nonparenchymal cell fractions of the liver revealed that the level dropped by about one third approximately 3.5 days after the Fe-PVS injection, showing the stimulated ferritin release at this stage. Results indicate that Kupffer cells in the liver play an important role in ferritin synthesis from the phagocytized iron compounds and that the iron is supplied for erythroid cell proliferation.
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PMID:An experimental study on the pathway of iron transfer from macrophages to erythrocytes in rat liver. 272 Jul 98

Recombinant clones of the chicken transferrin receptor gene and cDNA have been isolated and sequenced. Two highly conserved regions have been identified in the 3' noncoding sequence of the human and chicken TR gene. The conserved regions include sequences that have been shown to be involved in the iron-dependent regulation of human TR mRNA stability. These sequences can be modeled as two different types of RNA secondary structures, one containing stem-loop structures that are similar to the iron-responsive elements found in ferritin mRNA and the other being a stable, duplex/stem-loop structure. Both forms show considerable similarity between chicken and human mRNA. The expression of TR is developmentally regulated during erythroid maturation, and immature erythroid cells express exceptionally high levels of TR mRNA.
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PMID:Chicken transferrin receptor gene: conservation 3' noncoding sequences and expression in erythroid cells. 273 2

Iron status (expressed as serum ferritin and iron levels) has been compared in normal and in heterozygous beta-thalassemic subjects. A higher serum ferritin concentration has been found in beta-thalassemic males, showing, therefore, a shift towards super-normal values of the balance between tissue iron and serum ferritin levels. In beta-thalassemic subjects the serum ferritin levels have been found in the normal range and this seems to be correlated with an adequate and ready iron supply by protein transferrin to hyperplastic bone marrow. The higher urinary iron values in normal male subjects can be explained in this way: a large iron supply from the transferrin to the thalassemic erythroid cells limits the contribution from this protein to the urinary iron.
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PMID:[Findings in relation to serum and urinary iron in heterozygotic beta-thalassemia]. 276 66

Purified recombinant human heavy-chain (acidic) ferritin (rHF) was assessed in vivo in mice for effects on the proliferation (percentage of cells in S-phase) and absolute numbers of granulocyte-macrophage (CFU-GM), erythroid (BFU-E), and multipotential (CFU-GEMM) progenitor cells in the femur and spleen and on the nucleated cells in the marrow, spleen, and blood. rHF significantly decreased cycling rates and absolute numbers of marrow and splenic hematopoietic progenitors and marrow and blood nucleated cellularity. These effects were apparent in BDF1, C3H/Hej and DBA/2 mice and were dose dependent, time related, and reversible. Suppressive effects were noted within three hours for progenitor cell cycling, within 24 hours for progenitor cell numbers, and within 48 hours for circulating neutrophils. Additionally, hematopoietic progenitor cells in DBA/2 mice infected with the polycythemia-inducing strain of the Friend virus complex (FVC-P) were insensitive to the in vivo administration of rHF. These studies demonstrate activity of rHF in vivo on myelopoiesis of normal but not FVC-P-infected mice. Since rHF suppresses hematopoietic progenitor cell proliferation from normal donors in vitro and from normal mice in vitro and in vivo but does not suppress progenitor cells from patients with leukemia in vitro or from mice with FVC-P-infection in vitro or in vivo, rHF may be useful as a candidate adjunct molecule for the protection of normal hematopoietic progenitor cells during chemotherapy.
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PMID:Suppressive effects in vivo of purified recombinant human H-subunit (acidic) ferritin on murine myelopoiesis. 291 Mar 70

The phenotype and in vitro growth properties of blood and marrow blast cells detected in two neonates with Down's syndrome and a transient leukaemic picture are presented. In both patients, blast cells at diagnosis were heterogeneous and expressed predominantly megakaryocyte and erythroid markers identified by membrane fluorescence using monoclonal antibodies or ultrastructural detection of platelet peroxidase and ferritin. An additional trisomy involving chromosome 22 was detected in blast cells from one patient. Blood and marrow cells colony-assays performed at diagnosis revealed precursors with an abnormal differentiation capacity similar to those found in acute myelogenous leukaemia colony assays. However, an unusual feature was the persistence of high numbers of precursor cells (namely erythroid) following a normal differentiation pathway. Phenotypically and cytogenetically abnormal cells spontaneously disappeared by week 4-6, but overt relapse occurred in one patient 20 months later. These results bring strong arguments in favour of the neoplastic nature of the transient leukaemic picture observed in some neonates with Down's syndrome. Furthermore, we suggest that this disorder can be individualized as a separate entity with specific phenotypic and biological properties.
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PMID:Characterization of the blast cell population in two neonates with Down's syndrome and transient myeloproliferative disorder. 295 79

Among nine cases of early erythroblastic leukemia previously diagnosed using a panel of antibodies, two patients have erythroid blasts expressing glycophorin A, seven patients have blasts with a more immature phenotype. These immature blasts were labeled by the FA6-152 monoclonal antibody when studied with the immunogold technique. The blasts exhibited large nucleoli, and their cytoplasm contained numerous ribosomes and large mitochondria. In the Golgi apparatus several granules resembled the theta granules as previously described and contained ferritin molecules in the absence of rhopheocytosis. A large proportion of these blasts exhibited a platelet peroxidase (PPO)-like activity. As the blasts from the two other patients with a more mature phenotype and glycophorin A reactivity lacked this PPO, this enzyme seems to be restricted to the more immature cells. Since in these leukemic samples immature erythroid blasts were admixed to promegakaryoblasts, immunogold labeling was also performed with antiplatelet antibodies. This latter population which was labeled with C17, a monoclonal antibody to platelet glycoprotein IIIa, showed strong PPO activity but lacked theta granules and ferritin. In the normal bone marrow enriched by panning for CFU-E (8%) and depleted in progenitors of other lineages, blast cells showing characteristics similar to leukemic erythroid blasts were seen. They exhibited theta granules and ferritin and a proportion of them also had a PPO-like activity. Thus, a PPO reaction is not restricted to the platelet-megakaryocyte line. In conclusion, a PPO-like activity and ferritin molecules were present in immature leukemic erythroid blasts. Similar cells could be identified from normal bone marrow.
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PMID:Ultrastructural and cytochemical characterization of blasts from early erythroblastic leukemias. 311 5

The late events of erythroid differentiation in Friend erythroleukemic cells (FELC), stimulated by 5-amino levulinic acid (5-ALA), were studied. Cultivation of the cells in 5-ALA-enriched media triggered a chain reaction, beginning with an immediate and rapid accumulation of endogenous porphyrins, in particular protoporphyrin and hemin. Incorporation of 14C-ALA was rapid and independent of dimethylsulfoxide (DMSO) induction. In parallel, on the second day of growth, a marked decrease in cell volume was elucidated by flow cytometry. The total protein content was reduced, while Fe uptake and hemoglobin synthesis were increased. The combination of DMSO and 5-ALA produced the most effective induction of the FELC, and the differentiation criteria were the most advanced. The cells exposed to the combined stimulation became loaded with heme and hemoglobin and their generation time was prolonged up to 35 h. Transmission electron microscopy of these treated cells showed a morphological alteration to pearlike cells, associated with a typical nuclear translocation phenomenon and a regional segregation of sialoglycoproteins. An uneven distribution of organelles was revealed; one part of the cell contained numerous ribosomes and the nucleus, while the other part was hemoglobinized, contained mitochondria, and the outer membrane was heavily labeled with ferritin hydrazide, a marker for sialoglycoproteins. The enhanced stimulation of Friend cells by 5-ALA promoted an advanced step of erythroid maturation that has much in common with the late events of normal nuclear extrusion process.
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PMID:Stimulation of Friend erythroleukemic cell cytodifferentiation by 5-amino levulinic acid; porphyrins, cell size, segregation of sialoglycoproteins, and nuclear translocation. 316 53

Bone marrow cells from patients with leukemia, myelodysplastic syndromes, cancer, and other disorders on a phase I clinical trial with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) were assessed in vitro for numbers of granulocyte-macrophage (CFU-GM), erythroid (BFU-E), and multipotential (CFU-GEMM) progenitor cells, and for growth patterns (colony-to-cluster ratio) of CFU-GM, cycling rates of CFU-GM, and responsiveness in vitro to colony-stimulating and colony-inhibiting factors. The colony-to-cluster ratio of CFU-GM and the dose-response curves of CFU-GM to stimulation by rhGM-CSF in vitro did not change during the clinical trial. However, the percentage of CFU-GM in DNA synthesis, which is a measure of the proliferative rates of these cells, determined by the high specific activity tritiated thymidine kill technique in vitro, was markedly enhanced in a reversible fashion after administration in vivo of rhGM-CSF. The increased cycling rates of CFU-GM were consistent with the induced increase in neutrophil counts in these patients that has been reported elsewhere. Additionally, marrow CFU-GM from patients given rhGM-CSF in vivo were increased in sensitivity to inhibition in vitro by recombinant human H-subunit (acidic) ferritin in two of eight cases, and were increased in sensitivity to inhibition by lower dosages of recombinant human tumor necrosis factor alpha in all patients evaluated. The sensitivity of CFU-GM to inhibition in vitro by recombinant human interferon gamma and prostaglandin E1 did not change during the clinical trial. These studies demonstrate that the rhGM-CSF is having an effect on CFU-GM in the patients on the phase I clinical trial. This information may be of significance in planning future clinical studies combining rhGM-CSF with chemotherapy and/or other biotherapy.
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PMID:Growth characteristics of marrow hematopoietic progenitor/precursor cells from patients on a phase I clinical trial with purified recombinant human granulocyte-macrophage colony-stimulating factor. 326 May 58


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