Binding of Human Serum Ferritin to Concanavalin A

1. A high proportion of the ferritin in normal serum binds to concanavalin A. Binding is prevented by the addition of α-d-methylglucoside to the reaction mixture. 2. Ferritin in extracts of normal heart, liver and spleen or serum ferritin from patients with massive hepatic necrosis does not bind to concanavalin A. 3. Isoelectric focusing of preparations of serum ferritin from patients with primary haemochromatosis shows that the ferritin fraction binding to concanavalin A consists, predominantly, of the more acidic isoferritins. 4. These findings suggest that carbohydrate residues may be added to ferritin during its secretion into the plasma. Glycosylation may account for the heterogeneity of serum ferritin on isoelectric focusing. 5. Direct release of intracellular ferritin from damaged tissue may be indicated by an increase in the proportion of circulating ferritin which does not bind to concanavalin A. Such an increase has been found in sera from patients with iron overload.

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Sialic Acid and the Microheterogeneity of Human Serum Ferritin

Clinical Science ◽

10.1042/cs0580259 ◽

1980 ◽

Vol 58 (3) ◽

pp. 259-262 ◽

Cited By ~ 51

Author(s):

S. J. Cragg ◽

M. Wagstaff ◽

M. Worwood

Keyword(s):

Sialic Acid ◽

Human Serum ◽

Isoelectric Focusing ◽

Serum Ferritin ◽

Isoelectric Point ◽

Concanavalin A

1. Ferritin has been partially purified from the serum of patients with idiopathic haemochromatosis. 2. Incubation with neuraminidase of this partially purified serum ferritin eliminated much of the microheterogeneity of the protein so that only ferritin of isoelectric point approximately 5·8 was present. 3. There was no change in the total amount of ferritin present (measured immunologically) or in the percentage of ferritin binding to concanavalin A. 4. Incubation of liver, spleen or heart ferritin with neuraminidase did not change the isoelectric focusing patterns.

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Human serum ferritin G-peptide is recognized by anti-L ferritin subunit antibodies and concanavalin-A

British Journal of Haematology ◽

10.1111/j.1365-2141.1987.tb02271.x ◽

1987 ◽

Vol 65 (2) ◽

pp. 235-237 ◽

Cited By ~ 50

Author(s):

Paolo Santambrogio ◽

Anna Cozzi ◽

Sonia Levi ◽

Paolo Arosio

Keyword(s):

Human Serum ◽

Serum Ferritin ◽

Concanavalin A

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The Source of Serum Ferritin during Infection. Studies with Concanavalin A–Sepharose Absorption

Clinical Science ◽

10.1042/cs0590385 ◽

1980 ◽

Vol 59 (5) ◽

pp. 385-387 ◽

Cited By ~ 18

Author(s):

G. Birgegård

Keyword(s):

Serum Ferritin ◽

Concanavalin A ◽

Normal Subjects ◽

Normal Serum ◽

Control Group ◽

Serum Samples ◽

Tissue Samples ◽

Group Of Seven ◽

Acute Infections ◽

Before And After

1. Serum samples were collected from ten patients hospitalized for acute infections and from a control group of seven normal subjects. Tissue ferritin was obtained by purification of ferritin from normal human liver and from the ferritin standard of a commercially available assay kit. 2. The serum and tissue samples were incubated with concanavalin A-Sepharose, which has the ability to bind normal serum ferritin. 3. Concanavalin A, a plant lectin which binds to glucose, can be coupled to Sepharose particles and by incubation and centrifugation ferritin in normal serum can be absorbed to about 70%. The serum and tissue samples were incubated with concanavalin A-Sepharose and the ferritin content was measured before and after. 4. It was found that ferritin in the serum of patients with acute infections was absorbed to the same extent as in normal serum (about 80%), irrespective of the initial value. Only about 20% of the tissue ferritin was absorbed. 5. It is concluded that the ferritin in serum during infection is of the same glucosylated type as the ferritin normally present in serum, whereas intracellular ferritin is not glycosylated. This indicates that the elevation of serum ferritin during infection is caused by a release along the normal pathways, i.e. an augmented synthesis, not by leakage from damaged cells.

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Detection of a glycosylated subunit in human serum ferritin

Biochemical Journal ◽

10.1042/bj1990565 ◽

1981 ◽

Vol 199 (3) ◽

pp. 565-571 ◽

Cited By ~ 83

Author(s):

S J Cragg ◽

M Wagstaff ◽

M Worwood

Keyword(s):

Molecular Weight ◽

Human Serum ◽

Serum Ferritin ◽

Apparent Molecular Weight ◽

Normal Serum

Ferritin was purified from the serum of two patients with idiopathic haemochromatosis. The protein contained three types of subunit--the H and L subunits of tissue ferritins (although only a trace of H could be detected) and a third subunit, ‘G’, with the highest apparent molecular weight. Only the ‘G’ subunit band stained for carbohydrate, indicating that a proportion of the subunits of human serum ferritin are glycosylated. Although serum was obtained from patients with idiopathic haemochromatosis, it is probable that the ‘G’ subunit is a component of normal serum ferritin.

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The effect of zinc deficiency and iron overload on endocrine and exocrine pancreatic function in children with transfusion-dependent thalassemia: a cross-sectional study

BMC Pediatrics ◽

10.1186/s12887-021-02940-5 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Suzan O. Mousa ◽

Ebtihal M. Abd Alsamia ◽

Hend M. Moness ◽

Osama G. Mohamed

Keyword(s):

Iron Overload ◽

Zinc Deficiency ◽

Serum Ferritin ◽

Serum Zinc ◽

High Serum ◽

Exocrine Pancreatic Function ◽

Normal Serum ◽

Pancreatic Function ◽

Serum Lipase ◽

Endocrine Pancreatic Function

Abstract Background Children with transfusion-dependent thalassemia (TDT) suffer from secondary hemosiderosis and the delirious effects this iron overload has on their different body organs, including the pancreas. They are also more prone to develop zinc deficiency than the general pediatric population. This study aimed to determine the effect of zinc deficiency and iron overload on the endocrine and exocrine pancreas in TDT children. Methods Eighty children, already diagnosed with TDT, were included in this study. We assessed the following in the participant children: serum ferritin, serum zinc, endocrine pancreatic function (oral glucose tolerance test (OGTT), fasting insulin level and from them, HOMA-IR was calculated), and exocrine pancreatic function (serum lipase and serum amylase). Results Forty-four TDT children had a subnormal zinc level, while 36 of them had a normal serum zinc level. TDT children with low serum zinc had significantly more impaired endocrine pancreatic function and an abnormally high serum lipase than children with normal serum zinc, p < 0.05 in all. Serum zinc was significantly lower in TDT children with serum ferritin above the ferritin threshold (≥2500 ng/ml) than those below (59.1 ± 20.2 vs. 77.5 ± 28.13), p = 0.02. TDT children, having a serum ferritin ≥2500 ng/ml, had significantly more frequently impaired endocrine pancreatic function and abnormally high serum lipase than TDT children below the ferritin threshold, p < 0.05 in all. Conclusion In children with transfusion-dependent thalassemia, zinc deficiency aggravates iron-induced pancreatic exocrine and endocrine dysfunction.

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