scholarly journals Detection of acyl-CoA-binding protein in human red blood cells and investigation of its role in membrane phospholipid renewal

1995 ◽  
Vol 306 (3) ◽  
pp. 793-799 ◽  
Author(s):  
H Fyrst ◽  
J Knudsen ◽  
M A Schott ◽  
B H Lubin ◽  
F A Kuypers
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Human Liver ◽  
Plasma Membranes ◽  
Binding Protein ◽  
Human Red Blood Cells ◽  
Low Concentrations ◽  
Membrane Bound ◽  
High Concentrations

Acyl-CoA-binding protein (ACBP) has been identified in a number of tissues and shown to affect the intracellular distribution and utilization of acyl-CoA. We have detected ACBP in the cytosol but not the membrane of human red blood cells and, using an e.l.i.s.a. with antibodies prepared against human liver ACBP, found that its concentration was 0.5 microM. To investigate the role of ACBP in human red blood cells, we added purified human liver ACBP and radiolabelled acyl-CoA to isolated membranes from these cells. ACBP prevented high concentrations of acyl-CoA from binding to the membrane but could not keep the acyl-CoA in the aqueous phase at low concentrations. This suggested the presence of a pool in the membrane with a binding affinity for acyl-CoA that was greater than that of ACBP for acyl-CoA. In the presence of lysophospholipid, this membrane-bound pool of acyl-CoA was rapidly used as a substrate by acyl-CoA:lysophospholipid acyltransferase (LAT) to generate phospholipid from lysophospholipid. We also found that ACBP-bound acyl-CoA was preferred over free acyl-CoA as a substrate by LAT. These results are the first documentation that human red blood cells contain ACBP and that this protein can affect the utilization of acyl-CoA in plasma membranes of these cells. The interactions between acyl-CoA, ACBP and the membrane suggest that there are several pools of acyl-CoA in the human red blood cell and that ACBP may have a role in regulating their distribution and fate.

Activation by N-ethylmaleimide of a latent K+-Cl- flux in human red blood cells

1984 ◽  
Vol 246 (5) ◽  
pp. C385-C390 ◽  
Author(s):  
P. K. Lauf ◽  
N. C. Adragna ◽  
R. P. Garay
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Sulfhydryl Group ◽  
Maximum Velocity ◽  
Coupled Transport ◽  
Human Red Blood Cells ◽  
Low Concentrations ◽  
Reactive Groups ◽  
High Concentrations ◽  
K Transport

Twenty to fifty percent of the ouabain-insensitive Na+ and K+ fluxes in human red blood cells are mediated by Cl(-) -dependent coupled transport (cotransport). In this paper we report on the effect of the sulfhydryl group reagent N-ethylmaleimide (NEM) on Cl(-) -dependent ouabain-insensitive Na+ and K+ fluxes in human red blood cells. We found that NEM altered Na+ -K+ cotransport and activated a latent Cl(-) -dependent K+ transport mode normally apparently silent. This conclusion was based on the following observations. 1) At low concentrations (0.25 mM) NEM abolished the bumetanide-sensitive Na+ efflux and had no effect, even at a 10-fold higher concentration, on the bumetanide-sensitive K+ efflux. 2) At concentrations above 0.1 mM, NEM stimulated Cl(-) -dependent K+ efflux that was only partially inhibited by high concentrations of bumetanide or furosemide. In experiments using Rb+ as a K+ analogue, NEM activated Rb+ influx by stimulating the maximum velocity and lowering the apparent external cation affinity. The data suggest the presence of chemically reactive groups in human red blood cells for both Cl(-) -dependent K+ transport activated by NEM and Cl(-) -dependent coupled Na+-K+ movements.

Effects of cadmium and zinc on calcium uptake in human red blood cells

1984 ◽  
Vol 247 (3) ◽  
pp. C143-C149 ◽  
Author(s):  
G. A. Plishker
Keyword(s):  
Red Blood Cells ◽  
Disulfide Bond ◽  
Blood Cells ◽  
Calcium Uptake ◽  
Sodium Potassium ◽  
Human Red Blood Cells ◽  
Low Concentrations ◽  
Influx Pathways ◽  
Extracellular Sodium ◽  
Passive Influx

Cadmium and zinc increased the accumulation of calcium in human red blood cells by increasing passive influx without enhancing the permeability to other ions. The effect of cadmium and zinc appeared specific to these metals, because barium, magnesium, cobalt, strontium, manganese, and nickel had no effect. Changes in calcium uptake by extracellular sodium, potassium, and pH were not altered by zinc and cadmium. Inhibition of calcium uptake by quinine, oligomycin, and iodoacetate was not affected by cadmium or zinc. These results suggest that cadmium and zinc increase calcium movement through normal influx pathways. Cadmium and zinc acted synergistically apparently by different mechanisms. Zinc and cadmium differentially affected calcium uptake in different extracellular calcium concentrations. The cadmium effect was increased by low concentrations of 2-mercaptoethanol and above pH 8.0, while the zinc effect was less sensitive to these factors. These findings suggest that the cadmium effect involves a disulfide bond between cysteinyl residues and the zinc effect involves a different site.

Role of FK506 Binding Protein on Tacrolimus Distribution in Red Blood Cells

2020 ◽  
Vol 37 (7) ◽  
Author(s):  
Naoki Yoshikawa ◽  
Tsubasa Yokota ◽  
Ayako Matsuo ◽  
Nobuhiro Matsumoto ◽  
Tomomi Iwakiri ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Binding Protein ◽  
Fk506 Binding Protein

Observed differences in dextran and polyvinylpyrrolidone as rouleaux-inducing agents

1980 ◽  
Vol 58 (3) ◽  
pp. 271-274 ◽  
Author(s):  
Lionel S. Sewchand ◽  
Dieter Bruckschwaiger
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Animal Species ◽  
Critical Concentration ◽  
Rbc Membrane ◽  
Low Concentrations ◽  
High Concentrations ◽  
Induced Aggregation ◽  
Do So

The effectiveness of dextran fractions (Dx-500, Dx-100, Dx-70) and polyvinylpyrrolidone (PVP-360, PVP-40) in inducing aggregation of red blood cells (RBC) was studied in a nonflowing environment. The Dx fractions, at low concentrations, induced aggregation of human RBC but failed to do so at high concentrations (concentrations greater than 70 g/L). The effect was different on RBC from animal species (cat and rabbit); aggregation increased steadily with the Dx concentration and there was no critical concentration beyond which Dx failed to induce aggregation. The PVP was found to be very effective, at all concentrations, in inducing aggregation of RBC from both human and the animal species. These results have a twofold significance: (1) they suggest that Dx and PVP, both neutral polymers, interact differently with the human RBC membrane; and (2) the association of Dx with the human RBC membrane is different from that with cat and rabbit RBC membranes.

scholarly journals Isolation and characterization of an age-related antigen present on senescent human red blood cells

Blood ◽  
1981 ◽  
Vol 58 (2) ◽  
pp. 341-349
Author(s):  
EM Alderman ◽  
HH Fudenberg ◽  
RE Lovins
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Double Immunodiffusion ◽  
Specific Density ◽  
Human Red Blood Cells ◽  
Rbc Membrane ◽  
Isolation And Characterization ◽  
Age Related ◽  
Membrane Bound

Autologous membrane-bound IgG was isolated from a subpopulation of human red blood cells (RBC) with specific density greater than 1.110, by affinity chromatography of purified RBC membrane glycoprotein preparations using immobilized wheat germ agglutinin and immobilized anti-human immunoglobulin (Ig) as immunoabsorbents. The Ig-containing population thus obtained, when further separated by chromatography on Sephadex G-200 in the presence of chaotropic agents, yielded four peaks (Ia, Ib, II, and III). Double immunodiffusion revealed the presence of Ig in the first three peaks (IgM in peak Ia, IgA in Ib, and IgG in II) but not in peak III. Peak III was precipitated by the Ig-containing peaks (Ia, Ib, and II) in immunodiffusion assays, suggesting that the antigenic membrane determinants responsible for the binding of autologous Ig to senescent human RBC were contained in this peak (III). Peaks Ia, Ib and II precipitate purified asialoglycophorin; peak III was reactive with purified autoantibodies directed against asialoglycophorin. These results suggest that an age-related antigenic determinant(s) present on senescent human RBC is exposed by desialylation of the major sialoglycoprotein component of the RBC membrane.

scholarly journals Localization of calcium in red blood cells.

1983 ◽  
Vol 31 (9) ◽  
pp. 1109-1116 ◽  
Author(s):  
M Borgers ◽  
F J Thone ◽  
B J Xhonneux ◽  
F F De Clerck
Keyword(s):  
Plasma Membrane ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Potassium Phosphate ◽  
Human Red Blood Cells ◽  
A 23187 ◽  
Nonionic Detergent ◽  
Capillary Endothelial Cells ◽  
Membrane Bound ◽  
Triton X

The distribution of calcium is demonstrated in human red blood cells (RBC) with a combined phosphate-pyroantimonate technique (PPA). Freshly collected blood and tissue biopsies were initially fixed in potassium phosphate-glutaraldehyde and the complexed calcium was subsequently visualized on Vibratome sections with potassium pyroantimonate. The majority of cells, both in isolated as well as "in situ" preparations, show a fine granular precipitate located at the inner leaflet of the plasma membrane. A minority of cells lack these membrane-associated deposits, exhibiting instead a random distribution of very fine precipitate in their cytoplasm. Capillary endothelial cells and pericytes are devoid of plasma membrane-bound precipitate. When irreversible crenation of RBC is induced by exposure to ionophore A 23187 and calcium, the sphero-echinocytes loose their membrane-bound precipitate, whereas the cells that retain their discocyte shape demonstrate the usual pattern of membrane-bound deposits. Contrarily, cells showing reversible shape changes induced by either A 23187-Ca2+ challenge, by adenosine triphosphate depletion during aging, or contact with lysolecithin, retain or regain the membrane-bound calcium. This cytochemical demonstrable calcium at the inner leaflet of the plasma membrane is probably bound to acidic phospholipids, since it is readily extractable with the nonionic detergent Triton X-100.

Sign in / Sign up

Export Citation Format

Share Document