Biomaterial Database

The labile iron pool in human erythroid cells. 2008

Eugenia Prus, and Eitan Fibach

Department of Haematology, Hadassah-Hebrew University Medical Centre, Jerusalem, Israel.

Although most cellular iron is firmly bound (e.g. in haemoglobin), some, the labile iron pool (LIP), is bound to low-affinity ligands. The LIP is regarded as the crossroads of cellular iron traffic. Using multi-parameter flow-cytometry of cells treated with the metal-sensitive sensor calcein and the cell-permeable chelator deferiprone, we studied LIP in various human erythroid cell populations in peripheral blood, bone marrow and culture. Erythroid maturation was found to be associated with a decrease in the LIP. In the peripheral blood, nucleated erythrocytes (normoblasts) had 5.8-fold and 8.8-fold greater LIP than reticulocytes and erythrocytes respectively. Early reticulocytes had 2.5-fold more LIP than late reticulocytes. In the bone-marrow and in culture, LIP decreased by c. 30-fold as early erythroid precursors matured to late precursors. Adding holo-transferrin to iron-depleted cultures elevated LIP by 3.9-fold. We also show that in beta-thalassaemia, a disease associated with iron-overload, erythrocytes and reticulocytes in the blood and erythroid precursors in culture have a significantly greater LIP than their normal counterparts. In conclusion, the LIP in erythroid cells is altered under physiological (maturation) and pathological (thalassaemia) conditions. The methodology presented might be useful for evaluating the LIP in various diseases and for studying the efficacy of iron-chelators.

UI	MeSH Term	Description	Entries
D007501	Iron	A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.	Iron-56,Iron 56
D007502	Iron Chelating Agents	Organic chemicals that form two or more coordination links with an iron ion. Once coordination has occurred, the complex formed is called a chelate. The iron-binding porphyrin group of hemoglobin is an example of a metal chelate found in biological systems.	Iron Chelates,Agents, Iron Chelating,Chelates, Iron,Chelating Agents, Iron
D011728	Pyridones	Pyridine derivatives with one or more keto groups on the ring.	Pyridinones
D012156	Reticulocytes	Immature ERYTHROCYTES. In humans, these are ERYTHROID CELLS that have just undergone extrusion of their CELL NUCLEUS. They still contain some organelles that gradually decrease in number as the cells mature. RIBOSOMES are last to disappear. Certain staining techniques cause components of the ribosomes to precipitate into characteristic "reticulum" (not the same as the ENDOPLASMIC RETICULUM), hence the name reticulocytes.	Reticulocyte
D001854	Bone Marrow Cells	Cells contained in the bone marrow including fat cells (see ADIPOCYTES); STROMAL CELLS; MEGAKARYOCYTES; and the immediate precursors of most blood cells.	Bone Marrow Cell,Cell, Bone Marrow,Cells, Bone Marrow,Marrow Cell, Bone,Marrow Cells, Bone
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D004900	Erythroblasts	Immature, nucleated ERYTHROCYTES occupying the stage of ERYTHROPOIESIS that follows formation of ERYTHROID PRECURSOR CELLS and precedes formation of RETICULOCYTES. The normal series is called normoblasts. Cells called MEGALOBLASTS are a pathologic series of erythroblasts.	Erythrocytes, Nucleated,Normoblasts,Proerythroblasts,Pronormoblasts,Erythroblast,Erythrocyte, Nucleated,Normoblast,Nucleated Erythrocyte,Nucleated Erythrocytes,Proerythroblast,Pronormoblast
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
D004920	Erythropoiesis	The production of red blood cells (ERYTHROCYTES). In humans, erythrocytes are produced by the YOLK SAC in the first trimester; by the liver in the second trimester; by the BONE MARROW in the third trimester and after birth. In normal individuals, the erythrocyte count in the peripheral blood remains relatively constant implying a balance between the rate of erythrocyte production and rate of destruction.	Erythropoieses
D005434	Flow Cytometry	Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.	Cytofluorometry, Flow,Cytometry, Flow,Flow Microfluorimetry,Fluorescence-Activated Cell Sorting,Microfluorometry, Flow,Cell Sorting, Fluorescence-Activated,Cell Sortings, Fluorescence-Activated,Cytofluorometries, Flow,Cytometries, Flow,Flow Cytofluorometries,Flow Cytofluorometry,Flow Cytometries,Flow Microfluorometries,Flow Microfluorometry,Fluorescence Activated Cell Sorting,Fluorescence-Activated Cell Sortings,Microfluorimetry, Flow,Microfluorometries, Flow,Sorting, Fluorescence-Activated Cell,Sortings, Fluorescence-Activated Cell