Cord Blood Erythrocytes Research Articles

In vivo lability of red cell phosphofructokinase in term infants: the possible molecular basis of the relative phosphofructokinase deficiency in neonatal red cells.

Cord blood erythrocytes from nine term infants were separated by density gradient centrifugation into cohorts of intact cells of progressively increasing density and compared with red cells treated in a similar manner from four healthy adults. Pyruvate kinase (PK), an age-dependent enzyme, progressively decreased in activity from the lightest to the heaviest fractions, in both neonatal and adult red cells, indicating that red cells from newborn infants exhibit the same relationship between red cell age and density that had previously been demonstrated in red cells from adults. The rate of decline of red cell PK activity was essentially the same in neonates and adults, whereas phosphofructokinase (PFK) activity in cord erythrocytes decreased at a significantly faster rate when compared to adults. These data suggest that PFK has an accelerated rate of in vivo decay in neonatal red cells and is an unstable enzyme in the newborn.

The Effect of Maternal Smoking on Cord Blood Erythroeytes

Summary: A matched controlled study of cord blood erythrocyte parameters has been carried out on infants of smoking and non‐smoking mothers. A highly significant (P < .001) increase in mean corpuscular volume in the infants of smoking mothers was observed which did not appear to be related to the number of cigarettes used. There was no significant change in the red cell count, but haemoglobin concentration and mean corpuscular haemoglobin showed a similar increase. Growth retardation has been observed in the infants of smoking mothers and a possible mechanism for this is postulated.

Immunologic study of the age-related loss of activity of six enzymes in the red cells from newborn infants and adults--evidence for a fetal type of erythrocyte phosphofructokinase.

Blood from 10 normal healthy adults and cord blood from 8 healthy full term infants were infiltrated through a mixture sulfoethylethycellulose-Sephadex G 25 in order to eliminate the platelets and the leukocytes. Then the erythrocytes were fractionated into young and old cells by centrifugation in microhematocrit tubes. The enzyme activity and the immunologic reactivity of glucose phosphate isomerase (EC.5.3.1.9), phosphoglycerate kinase (EC.2.7.2.3), pyruvate kinase (ec.2.7.1.40), glucose 6-phosphate dehydrogenase (EC. 1.1.1.49), and 6-phosphogluconate dehydrogenase (EC.1.1.1.44) were measured in every fraction. As previously reported, the enzyme activities were far higher in cord blood than in adult blood red cells; nevertheless, the age-related loss of enzyme activity was similar in both cord and adult blood. The decrease of the enzyme activity of glucose phosphate isomerase and phosphoglycerate kinase in old cells was singly associated with a lowered concentration of the enzyme-related antigen; by contrast, the age-related decrease of the enzyme activity of pyruvate kinase, glucose-6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase was associated with both a lowered concentration of the enzyme-related antigen and a lowered "molecular specific activity" (i.e., a lowered ratio of enzyme activity to enzyme-related antigen concentration). This phenomenon was especially marked for pyruvate kinase, which had a molecular specific activity in old cells that was 68% of that in young cells. Phosphofructokinase had a lower enzyme activity in cord blood erythrocytes than in adult blood erythrocytes; the difference was especially important in old cells from infants in which phosphofructokinase activity was 53% of that in old cells from adults. Phosphofructokinase from old cells of full term infants and from unfractionated cells from two premature infants (21 and 32 weeks of gestation) was less neutralized by anti-muscle phosphofructokinase serum and more inhibited by ATP than the enzyme from adult blood erythrocytes.

The selenium state of healthy children. I. Serum selenium concentration at different ages; activity of glutathione peroxidase of erythrocytes at different ages; selenium content of food of infants.

The selenium concentration of serum is age-dependent. The median value at birth (chi=50 X 10(-9)g/ml) amounts to half of the median value of adults (chi=102 X 10(-9)g/ml). After a decrease in early infancy to chi=34 X 10(-9)g/ml it steadily increases to chi=58 X 10(-9)g/ml in the second half of the first year, to chi=82 X 10(-9)g/ml in 1--5 year old children, and to chi=92 X 10(-9)g/ml in school children. The activities of the selenium containing enzyme glutathione peroxidase of erythrocytes are also reduced in early infancy (chi=7.2 +/- 0.36 U37/g Hb), whereas the enzyme activities of cord blood erythrocytes (chi=8.72 +/- 0.76 U37/g Hb) are in the same range as those of older children or adults. The selenium content of some commercially available milk formulas for infants are lower than those of human and cow's milk.

Heme synthesis in hereditary hemolytic anemias: decreased delta-aminolevulinic acid synthetase in hemoglobin Köln disease.

The activities of delta-aminolevulinic acid (ALA) synthetase and ALA dehydratase in cord blood erythrocytes of newborn infants and peripheral blood red cells of patients with beta-thalassemia major, beta-thalassemia intermedia, hemoglobin Köln (Hb Köln) disease, sickle cell anemia, and pyruvate kinase deficiency were studied. The activity of ALA dehydratase did not vary appreciably with the number of immature RBC (reticulocytes and nucleated red blood cells) or the severity of the hemolytic anemia except in pyruvate kinase deficiency. The activity of ALA synthetase was linearly correlated with the number of immature RBC (r=0.974, p is less than 0.001). The ALA synthetase activity was significantly decreased in the RBC of Hb Köln (p is less than 0.01) when compared with the activity in immature RBC of newborns and of patients with pyruvate kinase deficiency, sickle cell anemia, and thalassemia intermedia.

Riboflavin, FAD, Glutathione, and Active Glutathione Reductase in Neonatal Erythrocytes

Erythrocyte glutathione reductase (GR) activity of the neonate in the first and second days of life is elevated twofold over that of adults and is unrelated to intracellular concentrations of GSH, FAD, riboflavin plus FMN, or total flavin. These findings are similar to those reported in erythrocytes of cord blood. The conversion of GR from the inactive to the active form by in vitro FAD has been shown to be a useful index of riboflavin deficiency in adults and in older children, but is shown in this study to be rapidly changing during these first days of life.

Carbonic anhydrase isoenzymes in the erythrocytes of new-born premature and full-term infants

A specific and quantitative immunological method for the determination of human erythrocyte carbonic anhydrase isoenzymes B and C has been used to determine these enzymes in erythrocytes of umbilical cord blood. The investigations have shown a content of both isoenzymes less than 1 : 10 of that in adults. Premature infants have significantly lower values than full-term infants. The influence of carbonic anhydrase in the respiratory distress syndrome is discussed. No conclusions are drawn. The content of carbonic anhydrase in erythrocytes has been suggested as a laboratory parameter of maturity. In our investigations it does not seem to be useful for the evaluation of maturity.

Argininosuccinic aciduria: Perinatal diagnosis and early dietary management

Summary A diagnosis of argininosuccinic aciduria was confirmed in a neonate whose older sibling was known to be affected. Argininosuccinic acid (ASA) was found in amniotic fluid, cord serum, initial urine, and spinal fluid. Microscopic examination of hair revealed trichorrhexis nodosa. Argininosuccinase activity was absent in cord blood erythrocytes. Maternal ASA excretion increased during the pregnancy. This report confirms the value of amniotic fluid ASA determinations for rapid prenatal diagnosis and describes methods for diagnosis and treatment in the neonatal period.

RED CELL TRIOKINASE DEFICIENCY - ANOTHER BIOCHEMICAL CHARACTERISTIC OF THE FETAL ERYTHROCYTE

The erythrocytes of normal adults have the capacity to incorporate and metabolize dihydroxyacetone (DHA). This substrate has been found to be useful for the maintenance of 2, 3-diphosphoglycerate (DPG) in stored red cells. The metabolism of DHA by cord blood erythrocytes was examined in an attempt to find a substrate for DPG synthesis that bypassed the early steps in red cell glycolysis. When the cells from adults and infants were incubated in the presence of DHA (10 mM), pyruvate (10 mM), and inorganic phosphate (10 mM), the DPG level increased by 2.34 μmoles/ml RBC's in the adult samples but only increased by 0.1 μmoles/ ml in the cells of infants during a period of 2 hours. DHA consumption averaged 3.76 μmoles/ml RBC's/hr in the cells from adults but was only 1.16 μmoles/ml RBC's/hr in the erythrocytes of the newborn. Assays of triokinase, the enzyme responsible for the phosphorylation of DHA, were performed in the hemolysates from newborn and adult erythrocytes. Triokinase activity averaged 4.56 ± 0.69 units/100 ml RBC's in adults and was only 2.97 ± 0.54 units in the cells from newborns (p <.01). Relative triokinase deficiency appears to be another biochemical characteristic of the red cells of the newborn infant.

PHOSPHOLIPIDS OF RED CELLS AND BLOOD PLASMA IN ADULTS, NEWBORN INFANTS, AND PATIENTS WITH RH ERYTHROBLASTOSIS

The concentration of total and individual phospholipids was determined in erythrocytes and plasma of adults, neonates, and newborn infants with Rh erythroblastosis. After extraction the phospholipids were separated by one-dimensional, thin layer chromatography into six fractions: phosphatidylethanolamine, phosphatidylserine, phosphatidylcholine, lysophosphatidylcholine, sphingomyelin, and nonidentified phospholipids. In normal neonates the total amount of red cell and plasma phospholipids was significantly decreased (1.32±0.20 µmoles/ml plasma, p&amp;lt;0.001; 3.03±0.65x10-10 µmoles/erythrocyte, p&amp;lt;0.001) when compared with the data of the adults (2.88±0.69µmoles/ml plasma; 4.11± 0.37x10-10 µmoles/erythrocyte). All the individual phospholipids were diminished in the plasma. In erythrocytes only the amount of phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine was reduced, whereas the sphingomyelin content was unchanged, i.e., it was increased when expressed as percent of total phospholipids (adult blood erythrocytes 24.2±0.8%; cord blood erythrocytes 29.7±2.8%, p&amp;lt;0.001). Thus, the sphingomyehn/phosphatidylcholine ratio was markedly higher in cord blood erythrocytes (1.03) than in adult red cells (0.81). In newborn infants with Rh erythroblastosis, the decrease of total and individual red cell phospholipids was less striking than in normal neonates. In the plasma the phospholipid patterns of the two neonate groups were identical. It is suggested that the total and individual phospholipid alterations in fetal red cells might be due to the low plasma levels of phospholipids in neonates.

Erythrocyte metabolism of umbilical cord blood and venous blood during delivery

Nucleotides and other glycolytic intermediates of erythrocytes of umbilical cord blood and of maternal venous blood were compared. Hemoglobins and serum proteins were estimated simultaneously. Serum proteins showed quantitative differences in the fractions of albumins, γ-globulins, transferrin, haptoglobins and some others, with total proteins exceeding in all cases 6 g/100 ml of serum. It was found, that the presence of different hemoglobins in erythrocytes and the observed differences in the serum fractions did not influence the carbohydrate metabolism in erythrocytes of the newborn.

Erythrocyte lipids in the neonate.

Extract: The lipid composition has been characterized in erythrocytes obtained from the cord blood of fullterm normal infants. There is an increase in total lipid, lipid phosphorous and cholesterol per cell (total lipid = 6.45 × 10 -10 mg; Lipid P = 1.54 × 10 -11mg; cholesterol = 1.79 × 10 -10 mg) when compared with adult controls (total lipid = 5.07 × 10 -10 mg; Lipid P = 1.22 × 10 -11mg; cholesterol = 1.33 × 10 -10mg). Despite the increased lipid content, the percentages of total lipid comprised by lipid phosphorous and cholesterol are similar to those found in the adult (P = 2.40% of total lipid in infants, 2.41% in adults: cholesterol = 27.1% of total lipid in infants, 26.0% in adults). Phospholipid fractionation shows minor variations between the two groups. Cord blood erythrocyte phospholipid has 1.0% lysolecithin, 26.0% sphingomyelin, 27.7% phosphatidylcholine, 15.2% combined phosphatidylserine and phosphatidylinositol, and 29.1% phosphatidylethanolamine. Adult erythrocyte phospholipid has 1.2% lysolecithin, 24.1% sphingomyelin, 29.5% phosphatidylcholine, 13.1% combined phosphatidylserine and phosphatidylinositol and 31.2% phosphatidylethanolamine. Phospholipid fatty acid patterns in cord blood erythrocytes show an increased percentage of palmitic acid (cord = 21.3%, adult = 17.0%), stearic acid (cord = 16.3%, adult = 15.3%) arachidonic acid (cord = 19.6%, adult = 17.4%) and combined 22 and 24 carbon fatty acids (cord = 17.6%, adult = 16.3%) associated with decreased percentages of oleic acid (cord = 11.9%, adult = 14.6%) and linoleic acid (cord = 3.4%, adult = 10.9%).Speculation: The erythrocyte lipids of the newborn show deviations from the adult pattern which may have adaptive value for intrauterine life. These same adaptations may render the cell more vulnerable to oxidative damage in postnatal life.

Hexokinase isoenzymes in human erythrocytes.

The electrophoretic mobility of hexokinase from human erythrocytes and other tissues was studied with a new method that depends on the fluorescence of reduced nicotinamide-adenine dinucleotide phosphate for detecting enzyme activity on starch gel. The hexokinase of cord-blood erythrocytes has slightly different electrophoretic properties from that of adult red cells. Type I enzyme is split into type I(A) and type I(F); the latter is more intense in cord blood; in hemolyzates of adult blood, the activity of the two bands is usually about equal. No type II enzyme was found in cord blood. The double type I band was present in red cells from adult rabbits.

Reduction of methemoglobin in human adult and cord blood erythrocytes incubated with glucose or inosine.

Impaired reduction of methemo-globin to hemoglobin by erythrocytes from cord blood is observed with either glucose or inosine as substrate. This observation is consonant with the hypothesis that the decreased reduction is a result of diminished activity of the NADH2-methemoglobin reductase system in the erythrocytes of cord blood. Neonatal deficiency in the activity of this enzyme system may contribute significantly to the increased susceptibility of infants to toxic methemoglobinemia.

Sur les variations de quelques activités enzymatiques dans le globule rouge humain, au cours de diverses circonstances physiologiques et pathologiques

Variation of some Enzyme Activities in Human Erythrocytes in Various Physiological and Pathological Conditions Statistics based on 30 healthy adults allow a determination of the amount of reduced glutathione and of the activities of the following erythrocytic enzymes: glucose-6-phosphate dehydrogenase, glutathione reductase, fructose-1,6-diphosphate aldolase, pyruvate kinase, lactate dehydrogenase, catalase and acetylcholinesterase. 1. 1.Cord blood erythrocytes (20 subjects) were examined under identical conditions. Significant differences were found which are discussed as a function of the heterogeneity of the two erythrocyte populations on one hand, and on the other, as a function of the differences of capacity to keep the haemoglobin in a reduced state. 2. 2. 13 cases of various types of jaundice in newborn infants were analysed in regard to the activity of their erythrocyte enzymes. In comparison to that of normal newborn children, very little difference was found. 3. 3. 10 cases of anaemia of renal origin yielded erythrocyte enzymes of a very similar activity to those of the normal adult. 4. 4. 2 cases of anaemia, one aplastic, the other regenerative, were examined from the same aspect as the preceding cases. The variations in activity of both glutathione reductase and the enzymes associated with glucose metabolism—treated as a whole—are proposed as a test of the haematopoietic activity of bone marrow.

Light-chain heterogeneity of cold agglutinins.

Cold agglutinins with specificity to I or to i antigens of humanadult or cord-blood erythrocytes produced during the course of Mycoplasma pneumoniae infection and infectious mononucleosis contain light chains of K and L types. However, cold agglutinin isolated from the serums of patients with chronic cold-agglutinin hemolytic anemia contains only type K light chains. The experimental evidence suggests that some cold agglutinins contain both types of light chains in the same molecule.

Meth�moglobinbildung durch p-Hydroxylamino- und p-Nitrosobenzolsulfonamid in Nabelschnur- und Erwachsenen-Erythrocyten

1. Incubation of human adult and cord blood erythrocytes with 10−5 M p-hydroxylaminobenzenesulfonamide or p-nitrosobenzenesulfonamide resulted in a much faster methaemoglobin formation in the fetal erythrocytes (0.337 against 0.178 percent haemiglobin formation per min with p-hydroxylaminobenzenesulfonamide).

Comparative studies of oxygen equilibria of human adult and cord blood red cell hemolysates and suspensions

The oxygen equilibria of suspensions and hemolysates of human adult and cord blood erythrocytes have been compared. Dialyzed hemolysates of adult and cord blood red cells showed small, but distinct, differences in the Bohr effect. Changes in phosphate molarity of the buffer used for the dialysis resulted in identical changes in oxygen affinities. Suspensions of cord blood erythrocytes in 0.9 g % NaCl showed a marked increase in oxygen affinity when compared with similar suspensions of adult red blood cells. The same difference in the Bohr effect was observed as seen for dialyzed hemolysates. The oxygen equilibria of concentrated undialyzed hemolysates of cord blood erythrocytes were almost identical to those of cord blood cell suspensions; the Bohr effect, however, was increased. The equilibrium between oxygen and the corresponding adult hemolysates was notably changed; the affinities of these hemolysates were found higher than that of either cord blood cell suspensions or hemolysates. The oxygen affinities of red cell suspensions from a heterozygous carrier of the persistent high Hb-F anomaly with 34% Hb-F were indistinguishable from those of normal adult erythrocyte suspensions. The addition of notable quantities of KCN and of NaF to the 0.9 g% NaCl solution did not affect the oxygen affinities of suspensions of both adult and cord blood erythrocytes. Hypotonic cell suspensions (in 0.6 g% NaCl) demonstrated increased oxygen affinities and a slight decrease in the Bohr effect; the effect of hypotonicity was the same for both cell types. Treatment of cord blood erythrocytes with a hypertonic solution (2.5 g% NaCl) resulted in decrease of the oxygen affinity. A similar treatment of adult erythrocytes increased the oxygen affinity, especially at pH values of 6.9 and higher. The significance of these findings has been discussed. Our studies suggest that differences in cell membrane or cell organization may likely contribute to the observed difference in oxygen affinities of human adult and cord blood erythrocytes. The presence of a specific fetal hemoglobin in the erythrocyte influences the Bohr effect and possibly the pH inside the cell, but not the oxygen affinity.

SEROLOGIC INVESTIGATIONS OF HUMAN HEMOGLOBINS. II. ANTIBODIES PRODUCED BY ISOLATED HUMAN HEMOGLOBIN TYPES WITH KNOWN STRUCTURAL DIFFERENCES.

Abstract Antisera against different human hemoglobin types, produced in adult rabbits, have been studied by the agar-diffusion technique according to Ouchterlony. In addition to total hemolysates of red blood cells of normal individuals, of patients with sickle cell anemia and with homozygous Hgb C disease, and of cord blood erythrocytes, purified hemoglobin components have been investigated. This purification was achieved by chromatographic isolation of the hemoglobin components by use of carboxymethylcellulose and DEAE-cellulose chromatography. The following components were investigated: A 0 , A 1 , F 09 , F 19 , A 29 , A 2 1 (a genetic variant of A 2 ), Hgb-Lepore S 0 , C 0 , and Hgb-Bart's ( γ 4 ). All components—with the exception of Hgb-Bart's, which contained small quantities of the A 1 component; F 0 , which was contaminated with a small amount of the A 1 fraction; A 0 (CMC), which contained a small quantity of Hgb F 1 ; and C 0 , which may have contained small amounts of Hgb A 2 —were virtually free of contamination with other structurally different hemoglobin types or with nonhemoglobin proteins. The antisera were studied before and after absorption with excess of different antigens. The following antibodies were demonstrated: (1) anti α-chain antibody; (2) anti β-chain antibody; (3) anti γ-chain antibody; (4) anti δ-chain antibody; (5) antibody reacting with Hgb F, Hgb-Bart's, and Hgb A 2 , but not with Hgb A (relation between the γ and δ chains); (6) antibody reacting with Hgb A, Hgb S, Hgb C, Hgb A 2 , but not with Hgb F (relation between the β and δ chains); (7) antibody reacting with the "β" chain of Hgb-Lepore and weakly with Hgb A 2 (antibody against part of the β chain of Hgb-Lepore); (8) specific antibody against Hgb-Bart's ( γ 4 ); (9) specific antibody against the abnormal β chain of Hgb S; (10) specific antibody against the abnormal β chain of Hgb C. No antibodies were apparent reacting with Hgb A and not with its variants Hgb S and Hgb C. The results obtained make it necessary to assume that the β chain of Hgb A and the γ chain of Hgb F possess at least 2 antigenic sites, while the β chains of Hgb S and of Hgb C and the δ chain of Hgb A 2 are capable of producing at least 3 different antibodies. The occurrence of a specific anti-Bart's ( γ 4 ) antibody does indicate that the complete structure of a hemoglobin molecule may determine the formation of specific antibodies. The results obtained with Hgb-Lepore are less conclusive; the possibility of the production of a specific anti-Lepore antibody and of an antibody against the δ chain part of the "β" chain must be considered. No immunologic differences were demonstrable between A 0 and A 1 and F 0 and F 1 under our experimental conditions.

A comparative study of enzymic activities in normal adult and cord blood erythrocytes as related to the reduction of methemoglobin

The problem under consideration was why cord blood with an increased tendency to form methemoglobin and a decrease in a methemoglobin reducing system did not show an increased level of methemoglobin. A comparative study was conducted of 6 important intra-erythrocytic enzymes, namely DPNH methemoglobin reductase, TPNH methemoglobin reductase, glucose-6-phosphate dehydrogenase, glutathione reductase, lactic and malic dehydrogenases. In cord blood samples there are found to be a significant decrease in the DPNH methemoglobin reductase activity and a highly significant increase in the activities of glucose-6-phosphate dehydrogenase and glutathione reductase. It was postulated that the expected accumulation of methemoglobin in cord blood samples was prevented by an increased reduction of methemoglobin by reduced glutathione which was shown to be formed at a greater rate in cord blood.