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D J Anstee

Publications and source records attributed to D J Anstee.

At least 127 records · Page 7Linked to original sources
PubMed1980

Blood group MNSs-active sialoglycoproteins of the human erythrocyte membrane.

The human erythrocyte membrane contains at least four different PAS-staining sialic acid-rich glycoproteins. The major sialoglycoprotein, which carries blood group M or N antigen activity, has been extensively characterized. The Ss antigens are located on a minor sialoglycoprotein, which also has "N' activity. The amino acid sequence at positions 1 and 5 of these glycoproteins correlates with the presence of M or N antigen activity. Little is known about the other minor sialoglycoproteins (beta and gamma). Membranes from erythrocytes of type (En(a-)Fin lack the major MN-active sialoglycoprotein; those from S-s-erythrocytes lack normal Ss-active sialoglycoproteins, although they contain an abnormal component that may be an altered Ss glycoprotein. Mk Mk cells lack both the MN- and Ss-active glycoproteins. These sialoglycoprotein-deficient cells are found in apparently healthy individuals. The sera of individuals with sialoglycoprotein-deficient cells may contain antisialoglycoprotein antibody, which has properties similar to those of auto-anti-Pr. Miltenberger Class III, IV, and VI erythrocytes have abnormal Ss-active sialoglycoproteins. Component beta appears altered in Miltenberger Classes I and II. These abnormalities may account for the unique serological properties of Class I, II, III, IV, and VI erythrocytes. Membranes from erythrocytes of type EnU K/Mk, Miltenberger Class V, and Ph contain abnormal sialogylcoproteins that may result from fusion of the genes that give rise to the Mn-and Ss-active sialoglycoproteins. If this is so, then the genes giving rise to the MN and Ss glycoproteins must be adjacent on the same chromosome.

Antibodies↗
PubMed1979

Abnormal blood-group-Ss-active sialoglycoproteins in the membrane of Miltenberger class III, IV and V human erythrocytes.

1. We have studied the inherited changes occurring in the sialoglycoproteins of membranes from erythrocytes of type Miltenberger Class III (Mi.III), Miltenberger Class IV (Mi.IV) and Miltenberger Class V (Mi.V) by using sodium dodecyl sulphate/polyacrylamide gel electrophoresis and lactoperoxidase radioiodination. 2. Mi.III erythrocytes lack the normal blood-group-Ss-active sialoglycoprotein but contain an unusual s-active sialoglycoprotein of higher apparent molecular weight. A similar abnormal S-active sialoglycoprotein appears to occur in Mi.IV erythrocytes. 3. The Mi.V condition is associated with the hemizygous absence of both the normal blood-group-MN-active sialoglycoprotein and the normal Ss-active sialoglycorprotein. However, a new sialoglycoprotein component is present in these cells that has properties characteristic of both the MN-active and Ss-active sialoglycoproteins. 4. Our results suggest that the new sialoglycorportein present in Mi.V erythrocytes is a hybrid of the normal MN sialoglycoprotein and an s-active sialoglycoprotein that has properties similar to the s-active sialoglycoprotein found in Mi.III erythrocytes. We suggest that the unusual Mi.V sialoglycoprotein is derived from chromosomal misalignment with unequal crossing-over between the genes for the MN- and Ss-active sialoglycoproteins in a manner similar to that which gives rise to haemoglobin Lepore. 5. Further studies of S-s-erythrocytes confirm that these cells lack normal Ss-active sialoglycoprotein, but contain an unusual component that shows some of the properties of the normal Ss-active sialoglycoprotein. 6. Analysis of erythrocytes of type Mk/Mi.III confirms that, in addition to the known hemizygous lack of the MN-active sialoglycoprotein, the Mk condition is also associated with a loss of the Ss-active sialoglycoprotein. 7. In order to facilitate discussion of the complex changes that occur in these variant erythrocytes, a new unified nomenclature is used for the erythrocyte sialoglycoproteins.

Autoradiography↗
PubMed1979

Probable EnaEn heterozygotes in two British families.

An investigation of the serological and biochemical properties of red cells in two unrelated British families revealed the probable presence of examples of the rare genotype EnaEn. In one family the En-modified red cells carried N-like determinants associated with s. In the other family M-like determinants associated with S were found.

Blood Group Antigens↗
PubMed1979

Two apparently healthy Japanese individuals of type MkMk have erythrocytes which lack both the blood group MN and Ss-active sialoglycoproteins.

A Japanese blood donor (H. T.) and his brother (M. S.) are the first homozygous MkMk individuals described; their red cells lack, as expected, known antigens of the MNSs blood group system and also have no demonstrable MN-active and Ss-active glycoproteins. Both MkMk individuals have a naturally occurring atypical antibody in their serum. The antibody in the serum of H. T. is inhibited by MNSs-active glycoprotein preparations from normal erythrocytes.

Animals↗
PubMed1979

Mk in three generations of an English family.

Mk was demonstrated in three generations of an English family. The propositus was detected as a result of an incompatibility in cross-match. General serological, biochemical and biophysical aspects have been studied.

ABO Blood-Group System↗
PubMed1978

Genetic variants involving the major membrane sialoglycoprotein of human erythrocytes. Studies on erythrocytes of type Mk, Miltenberger class V and Mg.

1. Membranes from erythrocytes heterozygous for the Mk and Miltenberger Class V (Mi.V) condition and membranes from erythrocytes homozygous for the Mg condition were studied by polyacrylamide-gel electrophoresis by using the periodate/Schiff stain binding of radioiodinated lectins and labelling with lactoperoxidase. 2. Both the Mk and Mi.V conditions are associated with a decreased content of the major blood-group-MN-active sialoglycoprotein. 3. An unusual blood-group-M-active membrane component was found in Mi.V cells of appropriate genotype. No comparably component was found in Mk erythrocytes. 4. The Mg antigen appears to result from a modification of the MN-active sialoglycoprotein found in normal cells. Our results suggest that the Mg sialoglycoprotein contains fewer sialotetrasaccharides than does the normal sialglycoprotein. This may result from changes in the amino acid sequence of the protein. 5. The results are discussed in relation to differences in the antigenic properties of Mk, Mi.V and Mg cells and their possible influence on the structure of the surface of each of these cells.

Antigens↗
PubMed1977

A carbohydrate-deficient membrane glycoprotein in human erythrocytes of phenotype S-s-.

1. We investigated the membranes of human erythrocytes which completely lack the blood-group antigens S and s (denoted as S-s-) as part of a study of the structure and function of the surface glycoproteins of the human erythrocyte. 2. The S-s-erythrocyte-membrane glycoprotein PAS-3 band was much less intensely stained in comparison with that of the glycoprotein from normal erythrocyte membranes. The S-s-membrane glycoprotein PAS-4 band also showed decreased staining. 3. Examination with the lectins from Maclura aurantiaca (Osage orange) and Arachis hypogaea (groundnut) showed that the PAS-3 glycoprotein of S-s-erythrocyte membranes lacked the receptors for these lectins that are present on glycoprotein PAS-3 from normal erythrocytes. 4. Radioiodination with lactoperoxidase showed the presence of the polypeptide of glycoprotein PAS-3 in S-s-cells, although it was more weakly labelled than the protein in the normal erythrocyte. 5. Our results show that the PAS-3 glycoprotein of S-s-erythrocytes is deficient in some of the carbohydrates present in the protein from normal erythrocytes. Glycoprotein PAS-4 of normal erythrocytes is shown to be a complex containing both glycoproteins PAS-1 and PAS-3.

Blood Group Antigens↗
PubMed1977

Freeze-fracture electron microscopy of human erythrocytes lacking the major membrane sialoglycoprotein.

Human erythrocytes of blood group En (a-), a rare homozygous condition involving a complete lack of the major sialoglycoprotein of the cell membrane (glycophorin A), were compared with erythrocytes from normal (En (a+)) individuals by freeze-fracture electron microscopy. No decrease in number, or variation in morphology, of the intramembranal particles of En (a-) cells was detectable. The results show that the erythrocyte sialoglycoprotein is not essential for the maintenance of the integrity of the intramembranal particles of the human erythrocyte membrane.

Erythrocyte Membrane↗
PubMed1977

Inherited sialoglycoprotein deficiencies in human erythrocytes of type En[a-].

We have investigated the membranes of erythrocytes from a family in which there is a genetic defect [previously described as the En[a-] condition[ resulting in the loss of the major erythrocyte sialoglycoprotein [PAS-i]. The results show that two different types of sialoglycoprotein deficiency can be distinguished within this family. We suggest that the En[a-] group of variants is more appropriately described as a class of sialoglycoprotein deficient erythrocytes. Using a new technique it is shown that the blood group M antigen of normal erythrocytes is found only on the erythrocyte sialoglycoprotein while in this family the M antigen is found on membrane components other than the sialoglycoprotein. Our results suggest that the amino acid sequence of the sialoglycoprotein is important in defining the difference between the blood group M and N antigens in normal erythrocytes.

Aminosalicylic Acid↗
PubMed1977

Screening of blood donors for IgA deficiency: a study of the donor population of south-west England.

Altogether 29 745 English blood donors were screened for IgA deficiency by double diffusion analysis; 57 had apparent absence of IgA, a frequency of 1:522. Further examination by the more sensitive haemagglutination inhibition assay revealed 34 samples having no detectable IgA, a frequency of 1:875. All donors negative by double diffusion analysis were tested for the presence of antibodies to IgA. Six class specific anti IgA antibodies and four anti IgA antibodies of limited specificity were detected. Three of these had the specificity anti alpha2 and one anti A2m(2). The 34 IgA deficient donors detected provide a source of IgA deficient blood for transfusion to patients with anti IgA antibodies.

Antibodies, Anti-Idiotypic↗
PubMed1976

Abnormal carbohydrate composition of the major penetrating membrane protein of En(a-) human erythrocytes.

The major penetrating membrane glycoprotein (band 3) was isolated from En(a-) and normal human erythrocytes. The two proteins differed only in carbohydrate composition. Band 3 from En(a-) erythrocytes contained greater amounts of galactose and N-acetyl-glucosamine. The loss of the sialoglycoprotein sialotetrasaccharides in the En(a-) cell is not compensated by the appearance of these units in band 3 of En(a-) erythrocytes.

Acetylglucosamine↗
PubMed1976

A method for the direct demonstration of the lectin-binding components of the human erythrocyte membrane.

1. A method which allows the characterization of lectin-binding components is described. This method should be useful in defining the nature and heterogeneity of these components in cell membranes. 2. The method, which we have used on erythrocyte "ghosts", involves the fixation of "ghost" components after sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and incubation with purified 125I-labelled lectins. 3. Each of the four lectins used shows an individual pattern of reactivity towards "ghosts" components. Band 3, the major membrane-penetrating glycoprotein, is bound by the lectins from Ricinus communis and Phaseolus vulgaris (phytohaemagglutinin) and by concanavalin A. The major erythrocyte sialoglycoprotein is bound by the lectins from R. communis, P. vulgaris and Maclura aurantiaca. 4. Three of the lectins displays binding for other membrane components, some of which are not demonstratable by conventional protein- and carbohydrate-staining techniques.

Binding Sites, Antibody↗
PubMed1976

The membrane change in En(a-) human erythrocytes. Absence of the major erythrocyte sialoglycoprotein.

We investigated the membrane of En(a-) human erythrocytes as part of a study of the structure and biochemical function of the surface glycoproteins of the mammalian cell. 2. En(a-) erythrocytes were selected because they have more extensive changes at the cell surface than any other known erythrocyte variant. 3. Our results show that in En(a-) erythrocytes: (a) the major membrane sialoglycoprotein is lacking; (b) the other major membrane-penetrating glycoprotein (band 3) has an altered electrophoretic mobility. 4. The apparent clinical normality of En(a-) cells suggests that the change in band 3 may compensate for the loss of the membrane sialoglycoproteins. It is clear that a viable erythrocyte can exist despite the absence of one of its major surface components.

Binding Sites, Antibody↗
PubMed1975

A natural anti-A agglutinin in the serum of the brown trout (Salmo trutta).

20% of normal serum samples from adult brown trout (Salmo trutta) possess an agglutinin for human erythrocytes with anti-blood-group A specificity. This agglutinin has properties which clearly distinguish it from the agglutinin with anti-(B+'P') specificity found in ova from fish of the same species and from anti-blood A antibodies found in human serum.

ABO Blood-Group System↗