Effect of Erythrocyte Deformability on in Vivo Red Cell Transit Time and Hematocrit and Their Correlation with in Vitro Filterability

1993 ◽  
Vol 46 (1) ◽  
pp. 43-64 ◽  
Author(s):  
H.H. Lipowsky ◽  
L.E. Cram ◽  
W. Justice ◽  
M.J. Eppihimer
Keyword(s):  
Transit Time ◽  
Erythrocyte Deformability ◽  
Red Cell

LACK OF EFFECT OF CORTICOSTEROIDS ON THE IN VIVO DISAPPEARANCE OF SULFHYDRYL-INHIBITED AND ANTIBODY-COATED ERYTHROCYTES

1964 ◽  
Vol 47 (3_Suppl) ◽  
pp. S28-S36
Author(s):  
Kailash N. Agarwal
Keyword(s):  
Red Cells ◽  
List Type ◽  
Red Cell

ABSTRACT Red cells were incubated in vitro with sulfhydryl inhibitors and Rhantibody with and without prior incubation with prednisolone-hemisuccinate. These erythrocytes were labelled with Cr51 and P32 and their disappearance in vivo after autotransfusion was measured. Prior incubation with prednisolone-hemisuccinate had no effect on the rate of red cell disappearance. The disappearance of the cells was shown to take place without appreciable intravascular destruction.

Age-dependent changes in volume and haemoglobin content of erythrocytes in the carp (Cyprinus carpio L.)

1989 ◽  
Vol 141 (1) ◽  
pp. 133-149 ◽  
Author(s):  
W. Speckner ◽  
J. F. Schindler ◽  
C. Albers
Keyword(s):  
Gel Filtration ◽  
Linear Increase ◽  
Human Erythrocytes ◽  
Main Peak ◽  
Red Cell ◽  
Human Haemoglobin ◽  
Cell Fractions ◽  
Haemoglobin Content

Carp erythrocytes were fractionated by angle-head centrifugation which yielded fractions with a linear increase in density. Haematological examinations revealed that the heavier red blood cells of carp had greater volumes (MCV), more haemoglobin (MCH) and higher haemoglobin concentrations (MCHC) than light ones. The same experiments with human red cell fractions yielded a decrease in MCV, constant MCH and an increase in MCHC. Haemoglobin content in individual erythrocytes was also determined by scanning stage absorbance cytophotometry to establish the frequency distribution of the cellular haemoglobin contents. In carp, the distribution was symmetrical with the means increasing with density. No such change with cell density was found in human erythrocytes. Both carp and human erythrocytes incorporated [2-14C]glycine in vitro. After gel filtration, radioactivity was detected in carp, but not in human, haemoglobin fractions. 14C was found in all three haemoglobin fractions, obtained by isoelectric focusing, and was present in the haem and in the globin. [2-14C]glycine-labelled erythrocytes were reinjected into chronically cannulated carp and followed in vivo for several months. With time, the main peak of scintillation counts shifted from red cell fractions of low to high density. This is considered as evidence that density and age of red cells in carp are positively correlated and that erythrocytes can synthesize haemoglobin while circulating in the peripheral blood.

scholarly journals Hypoxic stress underlies defects in erythroblast islands in the Rb-null mouse

Blood ◽  
2007 ◽  
Vol 110 (6) ◽  
pp. 2173-2181 ◽  
Author(s):  
Benjamin T. Spike ◽  
Benjamin C. Dibling ◽  
Kay F. Macleod
Keyword(s):  
Fetal Liver ◽  
Cell Maturation ◽  
Null Mouse ◽  
Hypoxic Stress ◽  
Red Cell ◽  
Exogenous Stress ◽  
Erythroid Maturation ◽  
Definitive Erythropoiesis

Abstract Definitive erythropoiesis occurs in islands composed of a central macrophage in contact with differentiating erythroblasts. Erythroid maturation including enucleation can also occur in the absence of macrophages both in vivo and in vitro. We reported previously that loss of Rb induces cell-autonomous defects in red cell maturation under stress conditions, while other reports have suggested that the failure of Rb-null erythroblasts to enucleate is due to defects in associated macrophages. Here we show that erythropoietic islands are disrupted by hypoxic stress, such as occurs in the Rb-null fetal liver, that Rb−/− macrophages are competent for erythropoietic island formation in the absence of exogenous stress and that enucleation defects persist in Rb-null erythroblasts irrespective of macrophage function.

scholarly journals Effect of oxalate and malonate on red cell metabolism

Blood ◽  
1987 ◽  
Vol 70 (5) ◽  
pp. 1389-1393
Author(s):  
E Beutler ◽  
L Forman ◽  
C West
Keyword(s):  
Pyruvate Kinase ◽  
Cell Metabolism ◽  
Inhibitory Effect ◽  
Red Cells ◽  
Red Cell ◽  
Acid Analogue ◽  
2,3 Dpg

The addition of oxalate to blood stored in Citrate-phosphate-dextrose (CPD) produces a marked improvement in 2,3-diphosphoglycerate (2,3-DPG) preservation; an increase in 2,3-DPG levels can also be documented in short-term incubation studies. Oxalate is a potent in vitro inhibitor of red cell lactate dehydrogenase, monophosphoglycerate mutase, and pyruvate kinase (PK). In the presence of fructose 1,6-diphosphate the latter inhibitory effect is competitive with phospho(enol)pyruvate (PEP). Determination of the levels of intermediate compounds in red cells incubated with oxalate suggest the presence of inhibition at the PK step, indicating that this is the site of oxalate action. Apparent inhibition at the glyceraldehyde phosphate dehydrogenase step is apparently due to an increase in the NADH/NAD ratio. Oxalate had no effect on the in vivo viability of rabbit red cells stored in CPD preservatives for 21 days. Greater understanding of the toxicity of oxalate is required before it can be considered suitable as a component of preservative media, but appreciation of the mechanism by which it affects 2,3-DPG levels may be important in design of other blood additives. Malonate, the 3-carbon dicarboxylic acid analogue of oxalate late did not inhibit pyruvate kinase nor affect 2,3-DPG levels.

scholarly journals The relationship between in vivo generated hemoglobin skeletal protein complex and increased red cell membrane rigidity

Blood ◽  
1988 ◽  
Vol 71 (5) ◽  
pp. 1427-1431 ◽  
Author(s):  
N Fortier ◽  
LM Snyder ◽  
F Garver ◽  
C Kiefer ◽  
J McKenney ◽  
...  
Keyword(s):  
Protein Complex ◽  
Sodium Dodecyl ◽  
Red Cells ◽  
Red Cell ◽  
Red Cell Membrane ◽  
Cellular Dehydration ◽  
Thalassemia Minor ◽  
Membrane Rigidity

Abstract In vitro induced oxidative damage to normal human RBCs has previously been shown to result in increased membrane rigidity as a consequence of the generation of a protein complex between hemoglobin and spectrin. In order to determine if in vivo generated hemoglobin-spectrin complexes may play a role in increased membrane rigidity of certain pathologic red cells, we measured both these parameters in membranes prepared from hereditary xerocytosis (Hx), sickle cell disease (Sc), and red cells from thalassemia minor (beta thal). Membranes were prepared from density-fractionated red cells, and membrane deformability was measured using an ektacytometer. Hemoglobin-spectrin complex was determined by sodium dodecyl sulfate (SDS)-polyacrylamide gel analysis, as well as by Western blot analysis using a monoclonal antibody against the beta- subunit of hemoglobin. For these three types of pathologic red cells, progressive cellular dehydration was associated with increased membrane rigidity and increased content of hemoglobin-spectrin complex. Moreover, the increase in membrane rigidity appeared to be directly related to the quantity of hemoglobin-spectrin complex associated with the membrane. Our findings imply that hemoglobin-spectrin complex is generated in vivo, and this in turn results in increased membrane rigidity of certain pathologic red cells. The data further suggest that oxidative crosslinking may play an important role in the pathophysiology of certain red cell disorders.

scholarly journals Protein - Quinone Interaction: In Vitro Induction of Indirect Antiglobulin Reactions With Methyldopa

Blood ◽  
1974 ◽  
Vol 43 (1) ◽  
pp. 85-97 ◽  
Author(s):  
Arlan J. Gottlieb ◽  
Harold A. Wurzel
Keyword(s):  
Gamma Globulin ◽  
Red Cell ◽  
Prolonged Incubation ◽  
Chemically Modified ◽  
Latex Beads ◽  
Structural Analogues ◽  
In Vitro Induction ◽  
Equilibrium Centrifugation

Abstract Methyldopa-treated gamma globulin can be demonstrated serologically on either the red cell surface or on latex beads by the indirect antiglobulin reaction. The development of a positive antiglobulin reaction was related to methyldopa concentration and the length and temperature of incubation of methyldopa with protein and could be partially inhibited by the addition of albumin to the incubation mixtures. After more prolonged incubation, antiglobulin positivity also developed with plasma-treated with methyldopa. 14C-methyldopa was covalently bound to gamma globulin. Aggregation of gamma globulin following treatment with methyldopa could be demonstrated by both sedimentation velocity and molecular weight determinations employing low-speed equilibrium centrifugation. Protein aggregation was a function of time, temperature, and methyldopa concentration. Detectability by the antiglobulin reaction, the darkening noted in solutions to which methyldopa or hydroquinone had been added, as well as the aggregation of protein was inhibited by a reducing agent which prevented formation of a quinone from the hydroquinone. Some of the immunologically atypical features of the sensitization of red cells by methyldopa or its structural analogues are explicable by the adherence, in vivo, of chemically modified, nonantibody gamma globulin which renders the red cell directly antiglobulin positive.

scholarly journals Reticulocyte Survival in Sickle Cell Anemia: Effect of Cyanate

Blood ◽  
1972 ◽  
Vol 40 (5) ◽  
pp. 733-739 ◽  
Author(s):  
Blanche P. Alter ◽  
Yuet Wai Kan ◽  
David G. Nathan
Keyword(s):  
Cell Survival ◽  
Sickle Cell ◽  
Fetal Hemoglobin ◽  
Red Cells ◽  
Red Cell ◽  
Hemoglobin Molecule ◽  
Red Cell Survival ◽  
And Control

Abstract Cyanate prevents sickling in vitro and apparently prolongs the survival of 51Cr-tagged sickle erythrocytes in vivo. Cautious interpretation is required because the effects of cyanate on 51Cr binding to sickle and fetal hemoglobin-containing red cells are unknown, and comparison of the effect of cyanate on sickle red cell survival to control red cell survival must be performed sequentially. We have studied the survival of sickle reticulocytes utilizing radioactive amino acids that are incorporated into hemoglobin. Two informed adult patients with sickle cell disease were studied. In each study, two 50-ml samples of blood were incubated separately with 14C- and 3H-leucine for 2 hr, after which 50 mM cyanate was added to one aliquot for 1 hr. The cells were then washed and reinfused. Frequent venous samples were obtained, and the specific activities of 14C and 3H in the hemoglobin were followed. The t ½ of the carbamylated cells was tripled, but remained below normal. This method provides a generally useful measurement of the influence of drugs bound to red cells on reticulocyte lifespan. The labels are incorporated into the hemoglobin molecule of the reticulocyte, and simultaneous comparison of the survivals of the same cohort of drug-treated and control cells is achieved.

scholarly journals Distinct, strict requirements for Gfi-1b in adult bone marrow red cell and platelet generation

2014 ◽  
Vol 211 (5) ◽  
pp. 909-927 ◽  
Author(s):  
Adlen Foudi ◽  
Daniel J. Kramer ◽  
Jinzhong Qin ◽  
Denise Ye ◽  
Anna-Sophie Behlich ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Wide Spectrum ◽  
Transcriptional Repressor ◽  
Erythropoietin Receptor ◽  
Red Cell ◽  
Genome Wide ◽  
Cytoplasmic Maturation ◽  
Adult Bone

The zinc finger transcriptional repressor Gfi-1b is essential for erythroid and megakaryocytic development in the embryo. Its roles in the maintenance of bone marrow erythropoiesis and thrombopoiesis have not been defined. We investigated Gfi-1b’s adult functions using a loxP-flanked Gfi-1b allele in combination with a novel doxycycline-inducible Cre transgene that efficiently mediates recombination in the bone marrow. We reveal strict, lineage-intrinsic requirements for continuous adult Gfi-1b expression at two distinct critical stages of erythropoiesis and megakaryopoiesis. Induced disruption of Gfi-1b was lethal within 3 wk with severely reduced hemoglobin levels and platelet counts. The erythroid lineage was arrested early in bipotential progenitors, which did not give rise to mature erythroid cells in vitro or in vivo. Yet Gfi-1b−/− progenitors had initiated the erythroid program as they expressed many lineage-restricted genes, including Klf1/Eklf and Erythropoietin receptor. In contrast, the megakaryocytic lineage developed beyond the progenitor stage in Gfi-1b’s absence and was arrested at the promegakaryocyte stage, after nuclear polyploidization, but before cytoplasmic maturation. Genome-wide analyses revealed that Gfi-1b directly regulates a wide spectrum of megakaryocytic and erythroid genes, predominantly repressing their expression. Together our study establishes Gfi-1b as a master transcriptional repressor of adult erythropoiesis and thrombopoiesis.

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