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)

Studies on the influence of erythropoietin (EPO) on granulocyte or monocyte function are scant. In this study, the effect of EPO on polymorphonuclear cell (PMN) respiratory burst activity was evaluated in a double-blind, placebo-controlled study in 22 patients on maintenance hemodialysis. As an index of phagocyte respiratory burst activity, the increase in 14CO2 production from labeled glucose-1-C, after challenge with latex and zymosan, was measured on predialysis whole blood samples, before and after EPO-treatment. As controls, 56 nonuremics and 49 non-EPO-treated hemodialysis patients were evaluated. Before EPO treatment 14CO2 production was depressed to 75.7% (latex) and 54.6% (zymosan) of healthy controls (P less than 0.01). A marked improvement was observed after a mean treatment period of 4 months (latex, 115 +/- 12 to 172 +/- 14; zymosan, 178 +/- 19 to 412 +/- 36 dpm/10(3) PMN, P less than 0.01). Placebo treatment induced no changes. The improvement became more pronounced with prolongation of treatment. A significant correlation between hematocrit and 14CO2 production was observed in the EPO treatment group (latex: n = 44, r = 0.47, P less than 0.05; zymosan: n = 44, r = 0.57, P less than 0.001). No correlation was found with serum ferritin. We conclude that the depressed phagocyte glycolytic activity of hemodialyzed uremics is normalized during correction of anemia by EPO. This may be attributed to factors other than a reduction in the body iron stores.
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PMID:Correction of deficient phagocytosis during erythropoietin treatment in maintenance hemodialysis patients. 156 25

Peripheral blood mononuclear cells of a patient with cyclic neutropenia release a high molecular weight substance (over 300,000) inhibiting normal CFU-GM cells to enter the S-phase of cell cycle. The inhibitor was released predominantly in the neutropenic phase of the disease, while in the period of normal granulocyte count the release was lower or undetectable. Also sensitivity of patient's bone marrow CFU-GM cells to similar high molecular weight inhibitor produced by ML-2 cell liner or to human placental ferritin varied within the disease cycle. CFU-GM in the normal granulocyte count period were sensitive to the inhibitors, but CFU-GM in the neutropenic phase were resistant.
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PMID:Inhibitor of granulopoiesis in human cyclic neutropenia. 170 97

The effects of recombinant murine macrophage inflammatory protein (MIP)-1 beta and MIP-2 on the suppressive activity of MIP-1 alpha were tested using colony formation by human and murine bone marrow burst-forming unit-erythroid (BFU-E), colony-forming unit-granulocyte erythroid macrophage, megakaryocyte (CFU-GEMM), and colony-forming unit-granulocyte macrophage (CFU-GM) progenitor cells. MIP-1 beta, but not MIP-2, when added with MIP-1 alpha to cells, blocked the suppressive effects of MIP-1 alpha on both human and murine BFU-E, CFU-GEMM, and CFU-GM colony formation. Similar results were observed regardless of the early acting cytokines used: human rGM-CSF plus human rIL-3, and two recently described potent cytokines, a genetically engineered human rGM-CSF/IL-3 fusion protein and MGF, a c-kit ligand. The more potent the stimuli, the greater the suppressive activity noted. Pulse treatment of hu bone marrow cells with MIP-1 alpha at 4 degrees C for 1 h was as effective in inhibiting colony formation as continuous exposure of cells to MIP-1 alpha, and the pulsing effect with MIP-1 alpha could not be overcome by subsequent exposure of cells to MIP-1 beta. Also, pulse exposure of cells to MIP-1 beta blocked the activity of subsequently added MIP-1 alpha. For specificity, the action of a nonrelated myelosuppressive factor H-ferritin, was compared. MIP-1 alpha and H-ferritin were shown to act on similar target populations of early BFU-E, CFU-GEMM, and CFU-GM. MIP-1 beta did not block the suppressive activity of H-ferritin. Also, hemin and an inactive recombinant human H-ferritin mutein counteracted the suppressive effects of the wildtype H-ferritin molecule, but did not block the suppressive effects of MIP-1 alpha. These results show that MIP-1 beta's ability to block the action of MIP-1 alpha is specific. In addition, the results suggest that MIP-1 alpha and MIP-beta can, through rapid action, modulate early myeloid progenitor cell proliferation.
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PMID:Macrophage inflammatory protein (MIP)-1 beta abrogates the capacity of MIP-1 alpha to suppress myeloid progenitor cell growth. 191 79

At present, no sufficient therapy for metastatic renal cell carcinoma is available. Several immunotherapeutical protocols have been studied, success rates, however, were inconsistent. The purpose of this study was to assess the pretherapeutic immunological status of 13 patients with metastatic and 16 patients with nonmetastatic renal cell carcinoma and of 15 healthy volunteers. Determined were differential blood counts, lymphocyte subpopulations, beta 2-microglobulin, tumor necrosis factor (TNF), neopterin, immunoglobulin, fibronectin and ferritin. Additionally, these parameters were recorded for monitoring an immunotherapeutical approach with the xenogeneic biological response modifier Keyhole limpet hemocyanine (KLH) in 10 patients with metastatic and in 5 patients with nonmetastatic disease. The pretherapeutic immunological status of patients with metastatic disease was characterized by significantly reduced T4-, T8- and B-cell counts. Significantly increased were granulocyte counts, beta 2-microglobulin, neopterin and TNF. In patients who did not suffer from metastases, only beta 2-microglobulin and neopterin were increased significantly. During immunotherapy, in patients with metastases, there was a decline of lymphocyte subsets and of the T4/T8-ratio, which correlated with progress of the disease. Humoral immune parameters showed no changes compared to pretherapeutic values. In patients who did not suffer from metastases, cellular immune parameters showed stable values during immunotherapy; neopterin, beta 2-microglobulin and TNF increased considerably. These findings indicate immunosuppression in patients with metastatic renal cell carcinoma, increasing with progression of the disease and possibly impairing the immunostimulating effects of biological response modifiers during immunotherapy. In conclusion, the clinical response of metastatic renal cell carcinoma to immunotherapy might be improved if the immunostimulant is combined with agents suitable to overcome immunosuppression, i.e. low doses of cyclophosphamide or inhibitors of prostaglandin synthesis. In addition, assessment of immune parameters for monitoring the actual immune status of a patient and the immunological effects of therapy was found to be a necessary part of immunotherapy.
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PMID:Immune status and immune therapy of renal cell carcinoma. 221 64

Serum ferritin levels are often elevated in patients with certain cancers and these elevations are, in part, derived from the tumors. In such patients, the increased levels of serum ferritin are associated with a poor prognosis. This association may be explained in part by biological effects of ferritin on lymphocytes: inhibition of E-rosette formation, masking of cell surfaces and suppression of lymphocytes' response to mitogens in vitro. The authors hypothesized that ferritins from tumor tissues also exert adverse effects on human granulocytes that are involved in tumoricidal activity. Three granulocyte functions were tested: nitroblue tetrazolium test, phagocytosis, and production of hydrogen peroxide. The results supported the authors' hypothesis: NBT reduction and phagocytosis are decreased in granulocytes exposed to ferritins, more so with tumor ferritins, than normal ferritin, and H2O2 production is less in granulocytes previously exposed to ferritins from tumor and nontumor tissues than cells not exposed to ferritins. However, the inhibitory effects of ferritins on H2O2 production can be reversed if granulocytes are further stimulated by phorbol myristate acetate (a membrane stimulant). If the elevated serum ferritin in cancer patients impairs granulocyte functions, in vivo, then it may increase the risk of infection, decrease tumoricidal host responses, and, thereby, contribute to the poor prognosis of these individuals.
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PMID:Effects of isoferritins on human granulocytes. 272 May 99

Iron, iron-binding capacity, lactoferrin and total protein were determined in the plasma and pleural fluid of 30 patients with cardiac failure (n = 10), infectious/inflammatory disease (n = 9) and metastatic carcinoma (n = 11). In 16 patients pleural transferrin and ferritin was also measured. Plasma iron and total iron-binding capacity were reduced in inflammatory and neoplastic disease, whereas hyposideremia with normal iron-binding capacity was seen in patients with heart failure. Plasma lactoferrin was reduced in metastatic carcinoma. Exudates (protein greater than or equal to 30 g/l; infectious/inflammatory: 9/9, carcinomatous: 10/11) had significantly higher iron, lactoferrin, transferrin and ferritin concentrations than transudates (protein less than 30 g/l; heart failure: 10/10, carcinomatous: 1/11). Statistically, infectious/inflammatory exudates could be distinguished from neoplastic exudates by a higher median iron concentration (non-parametric Wilcoxon-Mann-Whitney test). Overlap of the respective ranges, however, did not allow a clear-cut differential diagnosis in individual cases. Pleural lactoferrin concentrations, on the other hand, correlated with the pleural granulocyte count and nonspecifically reflect the degree of granulocytic inflammation. Positive pleural/plasma correlations of protein and of iron concentrations were found in exudates only. Within exudates and transudates, on the other hand, total protein correlated with transferrin but not with iron concentrations. Therefore, and because of the substantially higher pleural/plasma ratio for iron than for transferrin concentrations, a quantitatively important, non-transferrin bound iron pool in pleural fluids, most probably ferritin, must be assumed.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Iron and iron-binding proteins in the differential diagnosis of pleural effusion]. 276 88

In previous studies, antitransferrin receptor antibody 42/6 inhibited growth of normal granulocyte/macrophage progenitors and some malignant myeloid cells. In these studies, leukemia cell lines cultured without serum and fresh leukemia cells were used to investigate the roles of Fe, transferrin receptors, and transferrin in leukemia cell growth, and mechanisms of 42/6 inhibition and resistance. HL60 and KG-1 leukemia cells grown in serum-free medium were inhibited by 42/6. In contrast to results in fetal calf serum (FCS), soluble Fe (ferric nitriloacetate) reversed 42/6 growth inhibition of serum-free HL60 cells. When HL60 cells were adapted for growth in serum-free, transferrin-free medium, they became refractory to 42/6 growth inhibition. By using radiolabeled transferrin and 42/6, HL60 cells cultured in FCS and transferrin displayed similar quantities of transferrin receptors (29,000-30,000/cell) and similar Kd's (3.8-4.9 X 10(-9) M). Cells grown in transferrin-free medium showed a similar Kd (3.1 X 10(-9) M), but fewer transferrin binding sites (5,000/cell). Transferrin-independent cells contained a log higher concentration of intracellular ferritin. For both FCS and serum-free HL60 cells, calculated affinities for 42/6 were lower (5.7-10.0 X 10(-9) M), but the number of binding sites was three- to fourfold higher. To investigate further the relationship between receptor display and antibody inhibition in proliferating normal and malignant myeloid cells, simultaneous immunofluorescence was used to determine the cell cycle status of transferrin receptor-positive cells. Malignant cells in S + G2/M displayed approximately 50% of the amount of transferrin receptors detected in normal dividing colony-stimulating factor-stimulated marrow cells. Receptor display by dividing cells from two patients with acute nonlymphocytic leukemia was variable. When HL60 cells were exposed to dimethyl sulfoxide, transferrin receptor display decreased, and 42/6 growth inhibition was abrogated or greatly diminished. The presence of 42/6 did not prevent dimethyl sulfoxide-induced HL60 differentiation in serum-containing or serum-free cultures. We conclude that human leukemia cells require Fe for growth and that 42/6 inhibits transferrin-dependent cells by Fe deprivation. Some dividing normal and differentiating malignant cells display reduced transferrin receptors, and can also escape antibody inhibition. The increased ferritin levels and decreased transferrin receptors in transferrin-independent HL60 cells confirm the inverse relationship between cell ferritin content and transferrin receptor display. These studies indicate a critical role for Fe in leukemia cell growth and possible roles in cellular differentiation.
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PMID:Role of transferrin, Fe, and transferrin receptors in myeloid leukemia cell growth. Studies with an antitransferrin receptor monoclonal antibody. 298 53

We have prepared fluorescein isothiocyanate (FITC) conjugates of cationised ferritin (CF) and have investigated the usefulness of this CF-FITC to measure the negative cell surface charge of mouse bone marrow cells by flow cytometry. CF-FITC conjugates of low fluorochrome to protein ratios (F/P ratio) gave insufficient fluorescence and/or formed large aggregates when stored. CF-FITC conjugates of high F/P ratios (above 25) bound specifically to bone marrow cells, giving sufficient fluorescence, the intensity of which differed for the different cell types. When stored at -20 degrees C the CF-FITC was stable and could be used over prolonged periods. CF-FITC could be used to selectively enrich for pluripotent stem cells (CFU-S) and granulocyte/macrophage progenitors (CFU-C) by fluorescence activated cell sorting (FACS), although the CF-FITC binding to CFU-S and CFU-C was unexpectedly low. No correlation between CF-FITC fluorescence, cell size and electrophoretic mobility (EPM) was observed of bone marrow cells fractionated by free flow electrophoresis. Neuraminidase treatment to remove negatively charged sialic acid groups from the cell surface resulted in an increased binding of CF-FITC, although the EPM was decreased. The biotin conjugate of CF bound to bone marrow cells and could be visualised by avidin-FITC. The relative fluorescence intensity for the individual cell types showed a good correlation with the cell surface charge as determined by the EPM of the different cell types. The mechanism of binding CF-FITC to the cell surface was not by electrostatic interaction of the negative cell surface and positively charged CF because CF-FITC of F/P ratios of above 20 was negatively charged.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The use of cationized ferritin to measure cell surface charge of mouse bone marrow cells by flow cytometry. 308 17

Hematological data known or supposed to be influenced by individual sex hormones were evaluated in 18 untreated transsexuals (TS) and in 20 castrated or non-castrated TS on androgen and estrogen treatment, respectively. Profiting from a situation of clinically controlled hormonal sex-transformation it was tested, whether the circulating erythrocyte and granulocyte mass and iron metabolism are linked to a male and female sex-hormone constellation. The erythrocyte and granulocyte counts were significantly higher in untreated males and treated female-to-male TS than in untreated females and treated male-to-female TS. The unexpected finding of sex hormone-dependent granulocyte fluctuations was corroborated by parallel concentration changes of lactoferrin, a granulocyte-derived plasma protein. Iron metabolism as judged from plasma iron, total iron-binding capacity and serum ferritin was unaffected by sexual transformation. Plasma iron and the total iron-binding capacity did not differ significantly in untreated and treated TS of either type. The serum ferritin concentration, however, was significantly lower in untreated as well as in virilized females than in untreated and in feminized males, but was not significantly changed by long-term androgen or estrogen treatment. The present study demonstrates the potential of human transsexualism as a model for the study of sex-related biological processes.
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PMID:Sex-related differences in hematological values. A study on the erythrocyte and granulocyte count, plasma iron and iron-binding proteins in human transsexuals on contrasexual hormone therapy. 333 16

The human promyelocytic cell lines HL-60 can be induced to undergo differentiation to either granulocyte- or macrophage-like cells. We followed the changes in the synthesis and content of ferritin in this and other cell lines during differentiation. Ferritin content of HL-60 cells ranged from 11 to 81 fg/cell, depending on the clone tested. Following exposure to dimethylsulfoxide (DMSO) or retinoic acid (RA) an increase in ferritin and a decrease in total protein synthesis was observed, resulting in increased ferritin content, reaching a peak after 2 days. This increase occurred prior to the appearance of the typical morphological and functional characteristics of mature granulocytes. A correlation was found between concentrations of DMSO effective in inducing differentiation and the increase in ferritin content. Other inducers of granulocyte differentiation had a similar effect, while 12-O-tetradecanoylphorbol-13-acetate (TPA), an inducer of macrophage differentiation, had not. Another human cell line (U-937), which was induced into monocyte-like cells by RA, showed a twofold increase in ferritin content following differentiation. Addition of iron to the culture medium increased ferritin content of both differentiating and non-differentiating cells, but the former responded to lower concentrations of iron. The increase in ferritin during differentiation, however, was not related to an accelerated iron uptake. The present results suggest that changes in the intracellular ferritin of the developing myeloid cells may play a regulating role in the process of maturation of these cells.
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PMID:Changes in cellular ferritin content during myeloid differentiation of human leukemic cell lines. 397 11


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