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)

Extracts of glioblastomas and meningiomas were analysed by quantitative immunoelectrophoresis for the presence of foetal brain antigens and tumour-associated antigens, and levels of 2 normal brain-specific proteins were also determined. The following antibodies were used: monospecific anti-S-100 (glia specific); monospecific anti-GFA (glial fibrillary acidic protein), (astroglia specific); polyspecific anti-foetal brain (12-16th week of gestation); a polyspecific anti-glioblastoma antiserum, absorbed with insolubilized serum, haemolysate and normal brain extract; polyspecific anti-alpha-foetoprotein; and monospecific anti-ferritin. Using the antibodies raised against the tumours, several antigens not present in foetal or adult normal brain were found in the glioblastomas and the meningiomas. These antigens cross-reacted with antigens present in normal liver and were therefore not tumour-associated. S-100 was found in glioblastomas in approximately one tenth the amount in whole brain homogenate, whereas GFA was found 2-4 times enriched. The 2 proteins were absent in meningiomas. The possible use of the GFA protein as a marker for astroglial neoplasia is discussed. Five foetal antigens were found in foetal brain, but none in the tumours. alpha-Foetoprotein could only be demonstrated in foetal tissue extracts, including foetal brain, but not in tumours. Ferritin was detected in all tumour extracts, although the amounts determined were unrelated to histological tumour type.
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PMID:Antigens in human glioblastomas and meningiomas: Search for tumour and onco-foetal antigens. Estimation of S-100 and GFA protein. 6 76

Germinal cell tumors of the testis were studied for the presence of several tumor-associated antigens. Antisera were produced by immunizing rabbits with the purified antigens of alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), and hepatoma ferritin. Indirect immunofluorescence on embryonal carcinoma with or without teratoma components demonstrated that their staining range was 1--60 per cent with antiserum against AFP, 0--16 per cent with anti-serum against ferritin, and 0-40% with antiserum against CEA. Ferritin-like substances have not been described previously in germinal tumors of the testis. No staining was seen with seminoma cells or benign testicular tissues. Raised serum levels of AFP and the ferritin-like substance were related both to the presence of tumor and to dissemination of the disease. CEA occurred transiently in serum. Eleven patients with primary tumors had no antigen in their sera and have all survived, but the median survival time for 8 patients with either antigen in preoperative sera was 12 months. Five patients with advanced tumor in whom neither AFP nor ferritin was detected had a much longer median survival time (58 mo) than did 13 patients with high levels of serum AFP or ferritin (12 mo). The presence of either AFP or ferritin in sera of patients with primary or advanced disease, therefore, seemed to indicate a poor prognosis. The determination of both substances in serum may be useful in the follow-up of patients with certain types of testicular tumors. The proportion of cells containing each antigen varied in the different tumors. Similarly, each antigen could occur independently in serum. This suggested that certain germ cell tumors contained subpopulations of cells, which differed in their production and release of the antigens studied.
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PMID:Multiple antigens as marker substances in germinal tumors of the testis. 6 76

Serum ferritin concentrations were found to be raised, often considerably, in 58 of 76 black patients with primary liver cancer (PLC). No correlation could be demonstrated between the serum ferritin concentration and several other measurements, including the following: hepatic iron stores measured chemically, the size of the tumour, serum transaminase values, and the presence or absence of cirrhosis in the non-tumorous liver. There was, however, a negative correlation between serum ferritin and alpha-foetoprotein concentrations. Ferritin was purified from PLC tissue obtained from three patients at necropsy and the distribution of isoferritins was determined by isoelectric focusing. Acidic isoferritins similar to those previously found in PLC tissue were obtained. Their acidic nature was confirmed chromatographically using DEAE cellulose. Because the serum ferritin in patients with PLC probably consists of a mixture of normal and acidic isoferritins, it is likely that the serum assay used in the present study underestimated the actual concentrations present. With the development of an assay which utlises a specific antibody against acidic PLC isoferritins, serum ferritin may prove to be a second marker for PLC.
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PMID:Serum and tumour ferritins in primary liver cancer. 7 42

Ferritin in serum from patients with increased serum ferritin levels has been studied both quantitatively and qualitatively. All techniques utilized in these studies are suitable to be used as routine screening tests for large numbers of patients. Electroimmuno assay (EIA) has been compared with the solid phase immunoradiometric (IRMA) assay as a technique to determine serum ferritin concentration (r = 0.99) and is suggested as a useful alternative when determining ferritin concentrations above 500 microgram/l. Iron stained EIA gels have been used to indicate the iron content of the ferritin molecule in sera. This simple screening test has demonstrated that apoferritin is found more often than iron-rich ferritin in the serum of patients with elevated serum ferritin levels. Immunoelectrophoresis precipitin bands suggest the heterogeneity of ferritin in serum from different patients.
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PMID:Immunoradiometric and electroimmuno assay of increased ferritin and apoferritin levels in serum. 10 6

The auditory function of 75 children affected by homozygous beta0-thalassemia, managed with a low transfusion scheme and treated irregularly with low doses of desferrioxamine, and of 75 controls were examined. In 12 patients a mild bilateral conductive hearing impairment due to bony hypertrophy and/or adenoid hypertrophy was found. In 43 cases a moderate monolateral or bilateral sensory-neural hearing loss at high frequencies with recruitment phenomenon was observed. Ferritin levels were determined in a randomly chosen group of these patients with (14) and without heaing loss (11). In the subjects with sensory-neural hearing loss the mean ferritin levels were significantly higher than in those with no hearing defect. There was no obvious relation between sensory-neural damage on the one hand and Hb levels and unit of blood transfused on the other. The results of this study suggest that iron overload could be a cause of damage in the high frequency elements of the auditory mechanism. Intermittent hypoxia and slow 8th nerve compression due to bony hypertrophy as causes of auditory involvement are also discussed.
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PMID:Auditory involvement in thalassemia major. 10 1

Ferritin has been purified from normal full-term human placentae and its antigenic and molecular characteristics compared with adult liver ferritin. Placental ferritin is composed predominantly of a single subunit type, co-migrating with a liver ferritin standard on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Comparison of dose-response curves in an immunoradiometric assay indicated some tissue-specific antigenicity for placental ferritin. This was supported by immunofluorescence studies on cryostat sections of human placentae by using antibodies to placental and spleen ferritin. Specific staining for placental ferritin was demonstrated within placental syncytiotrophoblast, particularly localized towards the microvillus plasma membrane. Ferritin has also been shown by electrophoretic and antigenic analysis to be present in protein fractions solubilized from isolated human syncytiotrophoblast microvillus plasma-membrane preparations, suggesting that ferritin may play an active role in the transfer of iron from maternal transferrin across the syncytiotrophoblast plasma membrane.
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PMID:Characterization and localization of human placental ferritin. 11 99

This study describes the effect of ferritin on lymphocyte function in vitro. Peripheral blood lymphocytes isolated from normal donors were incubated with purified human splenic ferritin, and the mitogenic effect of phytohaemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen (PWM) and mixed lymphocyte reaction (MLR) were assessed by the uptake of 3H-thymidine (3H-TdR). Ferritin (0.25--5.0 micrograms/ml culture) caused a marked suppression of PHA nad Con A blastogenesis but had no suppressive effect on PWM-induced transformation. Maximal suppression was obtained at a ferritin concentration of 1 microgram/ml and this was not enhanced by increasing ferritin concentrations. Ferritin also reduced the Con A capping phenomenon in normal lymphocytes from 22% to 6%, suppressed the MLR reaction but had no effect on the ability of normal lymphocytes to form E, EA and EAC rosettes or on in vitro lymphocyte cytoxicity against the K-562 cell line. Visual proof of the suppressive effect of ferritin on mitogen induced blastogenesis was provided by scanning electron microscopy, and direct evidence for the ability of lymphocytes to bind ferritin was obtained from studies with radioiodine labelled ferritin. The above findings indicate that ferritin suppresses certain parameters of T-lymphocyte function in vitro. The relation of the present findings to recognized abnormalities of T-cell function encountered in certain neoplastic disorders associated with high serum ferritin levels is at present unknown.
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PMID:Suppressive effect of ferritin on in vitro lymphocyte function. 15 70

An affinity-purified plant lectin from Ricinus communis (RCAII) was shown to exhibit differential toxicity toward SV40-transformed 3T3 fibroblasts grown in vitro. When macromolecular synthesis was examined in SV3T3 and 3T3 cells, RCAII suppressed cell protein synthesis in the transformed line at lower concentrations (1/50 to 1/100) compared to the 3T3 line, and these effects were blocked by the RCAII inhibitors D-galactose or lactose. RNA and DNA synthesis and L-leucine transport were relatively unaffected by RCAII concentrations (greater than 1 mug/ml) that completely suppressed protein synthesis in both cell lines. The RCAII-mediated inhibition of cell protein synthesis required incubation times longer than 60 min, but quantitative cell binding studies with 125-I-RCAII indicated that the lectin binds to maximal levels in approximately 5 to 10 min, even at 4 degrees. During 10-min labeling experiments with 125-I-RCAII (1 mug/ml), it was demonstrated that the cell-bound lectin could be almost quantitatively removed from cells up to an additional 15 min after labeling without subsequent inhibition of protein synthesis. However, longer incubation times (greater than 30 min) after RCAII cell labeling and washing resulted in incomplete removal of cell-bound lectin (less than 20 to 30% of cell-bound lectin could be removed after a 60-min incubation). The longer incubation times (greater than 60 min) also resulted in almost complete inhibition of protein synthesis. Ferritin-conjugated RCAII (ferritin-RCAII) was used to follow the fate of the cell-bound lectin. Ferritin-RCAII bound rapidly (less than 10 min) to SV3T3 cell surfaces and could be blocked from labeling with lactose. After a 10-min incubation at 4 degrees in ferritin-RCAII solutions, the ferritin label was exclusively located at the extracellular surface in a random distribution. After washing and incubation at 37 degrees, the ferritin-RCAII induced clustering of its receptors (15 to 30 min) and eventually induced endocytosis (30 to 60 min). Further incubation (greater than 60 min) resulted in a predominantly intracellular localization of ferritin-RCAII inside endocytotic vesicles and free in the cell cytoplasm. That RCAII acts directly on protein synthesis after cell entry was confirmed with rabbit reticulocyte and mouse Krebs II ascites S30 cell-free protein synthesis system in diameter wit
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PMID:Mechanism of cell entry and toxicity of an affinity- purified lectin from Ricinus communis and its differential effects on normal and virus-transformed fibroblasts. 16 59

Ferritins purified from several normal and malignant rat tissues were examined for amino acid composition, content of tryptic peptides, available sulfhydryl groups and subunit sizes and proportion. Ferritin extracted from adult kidney, neonatal liver and hepatic and renal tumors differed from the ferritin of adult rat liver in migration on electrophoretic gels and in antibody affinity, but did not differ among themselves. Nevertheless, they showed distinctive differences in amino acid composition and tryptic peptide content. All of them and also adult liver ferritin contained two major species of subunits differing in molecular weight. The proportions of subunits, and the available sulfhydryl groups of the intact ferritin molecules, differed among these tissue ferritins. On the basis of amino acid and peptide content, the ferritins of hepatomas and the renal tumor analyzed showec the greatest similarity but not identity. The ferritin of neonatal liver was next most similar. Kidney ferritin differed considerably in composition from tumor and neonatal ferritins, while adult liver ferritin was the most extremely divergent of the series examined. A similar progressive difference was found on examining the proportions of subunits and sulfhydryl groups in these ferritins. However, changes in subunit proportion cannot explain the amino acid and peptide compositional changes.
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PMID:Structural differences in ferritins from normal and malignant rat tissues. 16 64

Ferritin and its protein subunits in rat hepatoma cell clone M-5123-C1 were biosynthetically labeled with [14C]leucine and 59Fe. Radioimmunoassays of ferritin/apoferritin and of protein subunits in the free polyribosome, membrane-bound polyribosome, smooth membrane, and cytosol fractions were done with ferritin-specific and subunit-specific rabbit IgG antibodies at various time intervals after pulsing. Much more 59Fe was bound by ferritin/apoferritin than by subunits in all of the cell fractions. Binding of iron to subunits may have been a random process. When hepatoma cells were simultaneously pulse-labeled with 59Fe and [14C]leucine, uptake of much of the 59Fe by ferritin occurred relatively early, in comparison to incorporation of [14C]leucine, in all of the cell fractions examined. Thus, 59Fe was readily incorporated into pre-existing ferritin. We conclude that most, if not nearly all, of the iron is incorporated after assembly of protein subunits.
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PMID:Biosynthesis of ferritin in rat hepatoma cells and rat livers. II. Binding of iron by ferritin protein. 19 51


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