Ferritin is the intracellular protein responsible for the sequestration, storage and release of iron. Ferritin can accumulate up to 4500 iron atoms as a ferrihydrite mineral in a protein shell and releases these iron atoms when there is an increase in the cell's need for bioavailable iron. The ferritin protein shell consists of 24 protein subunits of two types, the H-subunit and the L-subunit. ...

F erritin is a protein whose principal role within cells is the storage of iron in a nontoxic, but bioavailable, form. The assembled ferritin molecule, often referred to as a nanocage, can store up to 4,500 atoms of iron (for review see ref. 1). In contrast to cytosolic ferritin, serum ferritin is relatively iron-poor and may contain only a few atoms of iron. Ferritin does not have an obvious l...

1. A high proportion of the ferritin in normal serum binds to concanavalin A. Binding is prevented by the addition of alpha-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 ...

Electron-microscopic examination of rat reticulocytes and normoblasts incubated with transferrin conjugated to ferritin or ferritin-labeled antitransferrin revealed binding of ferritin conjugates to the surface membrane, and uptake of ferritin conjugates in micropinocytotic vesicles. No binding or endocytosis of ferritin was visualized when rat reticulocytes or normoblasts were incubated with f...

Electron-microscopic examination of rat or ferritin conjugated to nonspecific rabbit reticulocytes and normoblasts incubated lgG. These observations support the conwith transferrin conjugated to ferritin or cept that transferrin binds to a surface ferritin-labeled antitransferrin revealed membrane receptor and is subsequently binding of ferritin conjugates to the surinternalized by the developi...

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 no...

Following a pulse with 59Fe-transferrin, K562 erythroleukemia cells incorporate a significant amount of 59Fe into ferritin. Conditions or manipulations which alter the supply of iron to cells result in changes in the rate of ferritin biosynthesis with consequent variations in the size of the ferritin pool. Overnight exposure to iron donors such as diferric transferrin or hemin increases the fer...

background : the measuring serum ferritin level as a sensitive inflammatory biomarker might effectively predict preterm delivery, but the power and the best cut-off point of this biomarker for predicting preterm labor in iranian population has not been substantially identified. our purpose was to determine what concentrations of serum ferritin could identify patients at risk for preterm deliver...

Ascorbic acid retards ferritin degradation in K562 erythroleukemia cells leading to an increase in the availability of cellular iron (Bridges, K. R., and Hoffman, K. E. (1986) J. Biol. Chern. 261,14273-14277). To explore the mechanism of this effect, the influence of ascorbate on subcellular ferritin distribution was examined. Cellular ferritin was pulse-labeled with “Fe for 2 h, after which th...

We attempted to clarify the storage iron metabolism from the change in the serum ferritin level. We assumed that the nonlinear decrease in serum ferritin was caused by serum ferritin increase in iron mobilization. Under this assumption, we determined both ferritin and hemosiderin iron levels by computer-assisted simulation of the row of decreasing assay-dots of serum ferritin in 11 patients wit...