The spectrum of sickle cell disease.
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Adolescent↗
Biomedical subjects
H M Ranney
Publications and source records attributed to H M Ranney.
Growth of Plasmodium falciparum in human erythrocytes containing abnormal membrane proteins.
To evaluate the role of erythrocyte (RBC) membrane proteins in the invasion and maturation of Plasmodium falciparum, we have studied, in culture, abnormal RBCs containing quantitative or qualitative membrane protein defects. These defects included hereditary spherocytosis (HS) due to decreases in the content of spectrin [HS(Sp+)], hereditary elliptocytosis (HE) due to protein 4.1 deficiency [HE(4.1(0))], HE due to a spectrin alpha I domain structural variant that results in increased content of spectrin dimers [HE(Sp alpha I/65)], and band 3 structural variants. Parasite invasion, measured by the initial uptake of [3H]hypoxanthine 18 hr after inoculation with merozoites, was normal in all of the pathologic RBCs. In contrast, RBCs from six HS(Sp+) subjects showed marked growth inhibition that became apparent after the first or second growth cycle. Preincubation of HS(Sp+) RBCs in culture for 3 days did not alter these results. Normal parasite growth was observed in RBCs from one HS subject with normal membrane spectrin content. The extent of decreased parasite growth in HS(Sp+) RBCs closely correlated with the extent of RBC spectrin deficiency (r = 0.90). Homogeneous subpopulations of dense HS RBCs exhibited decreased parasite growth to the same extent as did HS whole blood. RBCs from four HE subjects showed marked parasite growth inhibition, the extent of which correlated with the content of spectrin dimers (r = 0.94). RBCs from two unrelated subjects with structural variants of band 3 sustained normal parasite growth. Decreased growth in the pathologic RBCs was not the result of decreased ATP or glutathione levels or of increased RBC hemolysis. We conclude that abnormal parasite growth in these RBCs is not the consequence of metabolic or secondary defects. Instead, we suggest that a functionally and structurally normal host membrane is indispensable for parasite growth and development.
Animals↗
Frequencies of Band 3 variants of human red cell membranes in some different populations.
A variant of Band 3, the major protein of the erythrocyte membrane, was observed by Mueller and Morrison in 1977 in 6-7% of healthy blood donors on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of erythrocyte membranes treated with pronase. Pronase treated red cells containing this first recognized variant [here designated 'Band 3-Memphis (m)'] section had two bands of about 63,000 and 60,000 Mr while pronase treated normal cells had only the lighter Mr band. The present study includes data on the frequency of variants resembling Band 3-Memphis in patients of different ethnic groups and on random donors obtained earlier in Memphis. These variants were detected by the original method of Mueller and Morrison and were not associated with recognized clinical or haematological abnormalities. Significantly higher gene frequencies for the variants of the (m) type were observed in American Indians, African Americans and Filipinos than in Caucasians; putative heterozygotes and homozygotes were identified among each of these groups. The frequency of silent Band 3 polymorphisms in different populations should be considered in the interpretation of clinical findings associated with the presence of Band 3 variants.
Anion Exchange Protein 1, Erythrocyte↗
Southeast Asian immigrants: the new thalassemias in Americans.
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Asia, Southeastern↗
Introduction: genetics in hematology III.
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Animals↗
Genetic epidemiology of structural mutations of the beta-globin gene.
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Anemia, Sickle Cell↗
Reverse phase high-performance liquid chromatography and secondary ion mass spectrometry. A strategy for identification of ten human hemoglobin variants.
Ten abnormal hemoglobins were detected and characterized in individual cases referred to our laboratory for evaluation of hematological problems. Six of these variants were electrophoretically silent and could be detected by reverse phase high-performance liquid chromatography (HPLC) analysis. HPLC was also used to analyze the tryptic peptides of each individual variant. In most of these variants, secondary ion mass spectra of the mixture of the tryptic peptides could reveal the aberrant peptide and predict possible substitution through the mass difference between the normal and abnormal peptide. The mass spectra of the isolated abnormal peptide generally contained sufficient fragment ions to define the position of the amino acid substitution, obviating the need for lengthy sequencing procedures. Combination of the two techniques.
Amino Acid Sequence↗
Some properties of hemoglobin mobile (alpha 2 beta 2 73 Asp----Val).
A hemoglobin variant was identified as hemoglobin Mobile in which valine replaces the normal aspartic acid at beta 73. Studies of its oxygen equilibria and of its interactions in gelation when mixed with hemoglobin S were carried out. Hemoglobin Mobile had an oxygen affinity lower than that of hemoglobin A, as observed by others. However, in mixtures with hemoglobin S, hemoglobin Mobile appeared to impair gelation or increase solubility to a slightly greater extent than did hemoglobin A. Beta 73 is a known site of intermolecular interactions in polymers of hemoglobin S. Our studies suggest that the impairment of hemoglobin S polymer formation by altered intermolecular interactions is significantly less in Hb Mobile than in Hb Korle-Bu in which beta 73 is asparagine.
Blood Protein Electrophoresis↗
Bimane fluorescent labels: labeling of normal human red cells under physiological conditions.
The bimane fluorescent labels, monobromobimane, dibromobimane, and monobromotrimethylammoniobimane, are derivatives of syn-9,10-dioxabimane:1,5-diazabicyclo[3.3.0]octa-3,6-diene-2,8-dione. They efficiently label hemoglobin (reactive thiol groups), membrane proteins, and glutathione of normal human red cells under physiological conditions. Monobromobimane and dibromobimane are effective on intact cells while red cell membranes may be impermeable to the positively charged monobromotrimethylammoniobimane, the latter being effective only on lysed cells. These bimane labels provide a class of labeling agents that may have wide applicability in biological materials.
Aza Compounds↗
The dissociation of NO from nitrosylhemoglobin.
The reaction between nitrosylhemoglobin and an excess of deoxymyoglobin has been used to study the kinetics of ligand dissociation from Hb4(NO)4 and Hb4(no)1 species. The kinetics of the dissociation of the first NO molecule from Hb4(no)4 was studied by the ligand replacement method. The results indicate that: (a) the ligand dissociation reaction in Hb4(NO)4 is a cooperative process. This is consistent with the results of Moore and Gibson (Moore, E.G., and Gibson, Q.H. (1977) J. Biol. Chem. 251, 2788-2794). (b) alpha and beta chains in the T state formed by adding IHP to Hb4(NO)4 show kinetic heterogeneity. (c) A similar kinetic heterogeneity is shown by alpha and beta chains in the species Hb4NO in the absence of IHP.(d) The value for the NO dissociation rate constant calculated from the slow phases observed in (b) and (c) is similar to that estimated for the R state. These results suggest that the R to T transition brought about with or without inositol hexaphosphate changes the ligand affinity of one type of the chains much more than of the other. On the basis of IR and EPR studies, it is suggested that alpha chains undergo larger functional changes in R to T transition (or vice versa) in nitrosylhemoglobin. The kinetic parameters for HbNO are compared with those of HbO2 and HbCO and the implications of the results for the reaction mechanism are discussed.
Carbon Monoxide↗
"Tension" on heme by the proximal base and ligand reactivity: conclusions drawn from model compounds for the reaction of hemoglobin.
The kinetic data on model compounds of hemoglobin indicate that in oxyderivatives ligand dissociation rates are sensitive to the "tension" exerted by the proximal base on the metal-to-ligand bond; the corresponding rates for carboxy derivatives are not sensitive to the tension. It is suggested that the metal-to-ligand bond becomes weaker with increased "pull" (or tension) on Fe from the proximal base due to the steric and/or electronic interaction between the ligand, the porphyrin ring, and the proximal base. In model compounds the linear heme Fe-to-CO bound vis-a-vis the bent heme Fe-to-O2 bond probably makes such interactions less significant in carboxy derivatives. It is proposed that the kinetic alpha,beta-chain nonequivalence in Hb4(O2)4 is due to the difference in the tension in the two chains on Fe by the proximal base. The absence of alpha,beta-chain differences large enough to show up in CO dissociation rates from Hb4(CO)4 is explained on the basis of lack of sensitivity of the Fe-CO bound to tension from the proximal base. The implications of the results for the observed cooperative effects in ligand combination (for CO) and dissociation (for O2 and NO) rates of hemoglobin have also been discussed.
Carbon Monoxide↗
Binding of 2,3-diphosphoglycerate by spectrin and its effect on oxygen affinity of hemoglobin.
The relationships between spectrin, a structural protein of the red blood cell (RBC) membrane facing the cytoplasm, and hemoglobin were studied. The oxygen-binding properties of stripped hemoglobin were not altered by the presence of spectrin, but the interaction of hemoglobin with organic phosphates was reduced by the addition of spectrin. The presence of the enzyme glyceraldehyde 3-phosphate dehydrogenase (G3PD), another component of the RBC membrane used as a control, did not change the oxygen affinity of either stripped hemoglobin or of hemoglobin solutions containing phosphates. Binding studies using the gel filtration method at pH 7.3 indicated reversible binding of 2,3-diphosphoglycerate to spectrin. A unit of 220,000 daltons was calculated to have seven binding sites and a binding constant of 1.2 X 10(4) M-1. A mechanism is proposed in which spectrin may facilitate oxygen transport for hemoglobin molecules reaching the membrane.
Binding, Competitive↗
Interaction of hemoglobin with red blood cell membranes as shown by a fluorescent chromophore.
Hemoglobin quenching of the fluorescence intensity of 12-(9-anthroyl)stearic acid (AS) embedded in the red blood cell membrane occurs through an energy transfer mechanism and can be used to measure the binding of hemoglobin to the membrane. The binding of hemoglobin to red cell membranes was found to be reversible and electrostatic in nature. Using a theory of energy transfer based on Förster formulation, the quantitative data for the binding were derived. The number of binding sites was found to be 1.4 +/- 0.2 X 10(6) molecules per cell and the binding constant was 0.85 X 10(8) M-1.
Energy Transfer↗
Classification and localization of hemoglobin binding sites on the red blood cell membrane.
The binding of hemoglobin to the red cell membrane was characterized over a wide range of free hemoglobin concentrations by measurement of membrane bound and supernatant hemoglobin. Scatchard analysis of the binding data revealed two classes of sites: high affinity sites with a binding constant of 1 X 10(8) M-1 and 1.2 X 10(6) sites per cell, and a second, low affinity class of sites with a binding constant of 6 X 10(6)M-1 and 6 X 10(6) sites per cell. The low affinity sites are shown to be nonspecific and appear to be a result of the ghost preparation. The high affinity sites are shown to be specific to the inner surface of the red cell membrane. The competition of hemoglobin and glyceraldehyde-3-phosphate dehydrogenase suggests band III proteins as a potential binding site for hemoglobin.
Binding Sites↗
Hemoglobinopathies.
The determination of the structure of hemoglobin is one of the milestones of molecular biology. This information has provided an intimate understanding of the way in which the molecule functions physiologically; Study of hemoglobin has proved relevant to a number of biomedical disciplines. This protein is a prototype of a general class of allosteric enzymes whose function depends upon transition from one conformation to another. Recently, attention has been focused on environmental factors, including 2,3-DPG, hydrogen ion concentration, and CO2, which can modify and perhaps regulate the behavior of hemoglobin within the red cell. Comparisons of primary amino acid sequences of animal hemoglobins have provided new and independent phylogenetic insights. Furthermore, surveys of human hemoglobin phenotypes have been of considerable utility in the study of population genetics. Finally, certain variants are responsible for specific clinical syndromes. As we shall discuss in detail, in most cases the clinical features can be directly attributed to lesions at a submolecular level. This chapter will first present a detailed account of interrelationships between hemoglobin structure and function. Secondly, we will consider the various factors in health and disease which can modify hemoglobin's physiologic role. This background information will be useful in the consideration of inherited and acquired disorders of hemoglobin structure and function.
Anemia, Hemolytic, Congenital↗
Dissociation of CO from carboxyhemoglobin.
The reaction between carboxyhemoglobin and reduced microperoxidase (MP): Hb4(CO)4 + 4MP=Hb4 + 4MPCO, recently reported by us, has been further studied. By generating species Hb4(CO), Hb4(CO)2, and Hb(CO)3 in the stopped flow cuvette by the reaction of dithionite with the species of the general formula Hb4(O2)x(CO)y(x + y=4) in the presence of microperoxidase it has been possible to determine the stepwise CO dissociation rate constants l4, l3, l2, and l1. The overall CO dissociation rate constant l, which is the same in this system as l4, is not affected by 2,3-diphosphoglyceric acid. The activation energy of the reaction is 21,400 cal in 15-25 degrees range. The ratio deltal/deltapH is approximately 3 in 6.5 to 7.5 pH range. The kinetic data indicate that, compared to HbO2, the contribution to the cooperativity of the dissociation rate constants of carboxyhemoglobin is greatly reduced. The ligand-dependent differences in the reactions of Hb with CO, O2, and NO suggest that in the combination reactions the ligand plays an active role in the rate-limiting step.
Carbon Monoxide↗
Hemoglobin M equon beta 41 (C7) phenylalanine leads to tyrosine.
A severe hemolytic crisis was observed in a 34-yr-old female of English-Irish extraction following a viral illness treated with acetaminophen. Heinz bodies and heat instability were present only during a transient hemolytic event. A challenge dose of acetaminophen caused no detectable hematologic abnormality. Structural studies of the hemoglobin during hemolysis and again after complete recovery localized the abnormality to tryptic peptide beta Tp-5, and automated sequencing of I 125-labeled beta chains indicated a replacement of phenylalanine (C7) beta 41 by tyrosine. Substitution of the next residue, phenylalanine (CD1) beta 42 by serine (Hb Hammersmith), has resulted in chronic severe Heinz body hemolytic anemia. The lack of chronic anemia in the present disorder may reflect the different relationships of beta41 and beta 42 and/or the similarities in volume and hydrophobicity of tyrosine and phenylalanine. It is suggested that substitution of tyrosine for phenylalanine in Hb Mequon may disturb the critical environment around the heme group and render it susceptible to oxidative denaturation in the presence of infections and/or drugs.
Adult↗