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D M Swallow

Publications and source records attributed to D M Swallow.

At least 73 records · Page 4Linked to original sources
PubMed1989

Three antibodies to human intestinal brush border membrane are characterized as anti-Le(a).

In the course of raising monoclonal antibodies to human colonic and small intestinal epithelium, three were isolated which recognized epitopes on many colonic glycoproteins and many jejunal glycoproteins taken from some individuals, but not on the same glycoproteins from others. The specificities of these antibodies were examined by carrying out inhibitions of the binding of the antibodies to the jejunal glycoproteins by blood group substances and purified oligosaccharides. The glycoproteins were separated by electrophoresis and transferred to nitrocellulose strips which were then used for the inhibition experiments. The results indicated that the antibodies bind to Le(a)-active structures. The conditions were determined for achieving red cell agglutination by two of the antibodies.

Animals↗
PubMed1988

Regional assignment of the gene coding for human sucrase-isomaltase (SI) to chromosome 3q25-26.

The gene coding for sucrase-isomaltase (SI) has recently been mapped to chromosome 3 using a cDNA probe to analyse DNA from somatic cell hybrids (Green et al. 1987). We have now used this same cDNA probe to obtain a regional localization of this gene. In situ hybridization to normal metaphase chromosomes and to chromosomes from individuals with balanced translocations suggests a regional assignment to chromosome 3q25-26.

Chromosome Mapping↗
PubMed1987

Identification of a monoclonal antibody-defined breast carcinoma antigen in body fluids.

The monoclonal antibody NCRC-11 defines antigens associated with secretory glandular epithelia as well as most epithelial malignancies. These components have been identified in, and isolated from, normal body fluids including urine and skim milk. The immunoadsorbent purified antigens from urine and milk were very similar to those purified from breast and ovarian carcinomas; by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE) and immunoblotting, NCRC-11 antibody-binding antigens from all sources were of high apparent molecular weight (greater than 400 kD) with the major component(s) present as a single band or a doublet. Also, by analysing epitope profiles, all purified antigen preparations were shown to react in a characteristic manner with a panel of monoclonal antibodies which were originally produced against human milk products or materials from tumours. Since it was shown that NCRC-11 antigens were released from tissues in a soluble form, the possibility that these antigens might represent a diagnostic marker for breast cancer was evaluated. The findings obtained indicated that NCRC-11 antigens were elevated in the serum of advanced breast cancer patients in comparison to healthy control females, so that access to the circulation was available to these products released from the tumour but not to those released from normal epithelia.

Aged↗
PubMed1987

The hypervariable gene locus PUM, which codes for the tumour associated epithelial mucins, is located on chromosome 1, within the region 1q21-24.

A single hypervariable autosomal gene locus, PUM, codes for a family of mucin-type glycoproteins present in human urine, and in several other normal and malignant tissues of epithelial origin. These mucins can be detected after electrophoresis using a series of monoclonal antibodies that show a pronounced tumour specificity on immunohistochemistry. Using a recently cloned cDNA, pMUC10, coding for the core protein of the PUM coded mucins, to probe DNA isolated from a series of human-rodent somatic cell hybrids, we have assigned the PUM locus to chromosome 1. This assignment was confirmed by in situ hybridization of pMUC10 to lymphocyte metaphase chromosomes and the gene was shown to be located within the region 1q21-24.

Animals↗
PubMed1986

Human biochemical genetics of enzyme proteins in the new age of molecular genetics.

Advances in protein biochemistry and immunology have had a major impact on the biochemical and genetical analysis of human proteins and have had applications in the analysis of the primary defects in metabolic disorders, as well as in cDNA cloning. The development and expansion of somatic cell genetic techniques has complemented conventional population and family study genetic methods. A large number of mammalian proteins undergo complex processing to achieve the synthesis of the biologically active protein. Much of this processing is under genetic control. Elucidation of these complexities requires a combination of biochemical, immunological and genetical approaches to determine the nature of the events involved.

Alleles↗
PubMed1986

Assignment of the human gene for uridine 5'-monophosphate phosphohydrolase (UMPH2) to the long arm of chromosome 17.

Two distinct isozymes of uridine 5'-monophosphate phosphohydrolase (UMPH) have been identified in mammalian cells. Both of these isozymes hydrolyse other pyrimidine nucleotides. One of the isozymes, UMPH2, is more active against deoxy-nucleotides than non-deoxy-nucleotides and has a wider substrate specificity. We examined the segregation of the human gene for UMPH2 in human-mouse somatic cell hybrids. Electrophoretic analysis of UMPH2 in hybrids suggested that the enzyme is a dimer. Human UMPH2 cosegregated with the long arm of chromosome 17 in the nineteen hybrids examined. The ease of separation of the rodent and human isozymes of UMPH2 and the relative simplicity of the enzyme assay suggest that UMPH2 may be a more useful marker gene for chromosome 17 than galactokinase.

5'-Nucleotidase↗
PubMed1986

Detection of the urinary 'PUM' polymorphism by the tumour-binding monoclonal antibodies Ca1, Ca2, Ca3, HMFG1, and HMFG2.

A series of human urinary mucin-like glycoproteins, previously detected using lectins to stain gels after electrophoresis, and showing genetic polymorphism (Karlsson et al., 1983) can also be detected using the tumour-binding monoclonal antibodies, Ca1, Ca2, Ca3, HMFG1, and HMFG2. The evidence from immunoprecipitation and immunoadsorbant chromatography experiments is that the epitopes recognized by these antibodies are carried on the same molecules as the lectin-binding determinants. The discovery that the antibodies bind specifically to a family of molecules which show genetic polymorphism provides a powerful new tool for the analysis of the material expressed aberrantly in cancer.

Antibodies, Monoclonal↗
PubMed1985

Human lactase and the molecular basis of lactase persistence.

Human lactase purified from detergent extracts of the total membrane fraction of postmortem jejunum by means of monoclonal immunoadsorbent chromatography appears to be a dimer of subunits identical in Mr (160K). Trypsin or papain removes a small hydrophobic anchoring peptide from each subunit to give a hydrophilic enzyme which no longer interacts with detergent micelles. Lactase hydrolyzes, besides lactose, cellobiose and the synthetic substrates, 4-methylumbelliferyl-beta-galactoside and beta-glucoside, as well as phlorizin; but it does not hydrolyze glucocerebroside. Phlorizin hydrolase is associated with lactase under all conditions investigated; coincident staining on immunodiffusion and immunoelectrophoresis, coincident elution on immunoadsorbent chromatography and on gel filtration in a dissociating buffer, and correlated reduction in activity in lactase-nonpersistent individuals. Adult and infant lactases are indistinguishable by titration or immunodiffusion against polyclonal rabbit antibodies. Adult individuals low in lactase activity also show a corresponding reduction in cross-reacting material. These observations suggest that lactase persistence is due to the continued synthesis of the infant enzyme.

Antibodies, Monoclonal↗
PubMed1984

The role of lysosomal sialidase and beta-galactosidase in processing the complex carbohydrate chains on lysosomal enzymes and possibly other glycoproteins.

Previous studies using the lectin RCA-I from Ricinus communis have indicated that several lysosomal enzymes in the fibroblasts of patients deficient in beta-galactosidase carry excess terminal galactose. Electrophoretic studies have shown that the same enzymes and the non-lysosomal adenosine deaminase also show excess terminal sialic acid in patients deficient in sialidase. In this paper we confirm, using Jack-bean beta-galactosidase, that the binding to RCA-I of the purified N-acetyl-beta-D-hexosaminidase from a patient with GM1 gangliosidosis depends on a terminal beta-linked galactose. We provide evidence, using bacterial sialidase and measuring the binding to RCA-I, for excess subterminal galactose on the enzymes of patients deficient in sialidase. We also show that adenosine deaminase from the fibroblasts of patients deficient in beta-galactosidase has increased binding to RCA-I. These observations suggest that in healthy individuals the carbohydrate structure of the precursors of lysosomal enzymes and possibly some other glycoproteins also includes extended carbohydrate side chains with terminal sialic acid and subterminal galactose, and that the mature enzyme extracted from tissues is the product of degradation.

Acetylglucosaminidase↗
PubMed1984

Glycoproteins in cystic fibrosis: a lectin binding study.

Ten lectins have been used to detect glycoproteins, after SDS polyacrylamide gel electrophoresis and gel isoelectric focusing, in fibroblasts, red cell membranes, urine, and plasma of patients and obligate heterozygotes with cystic fibrosis. No disease specific changes were detected but considerable individual variation was observed, some of which was attributed to known genetic polymorphisms unrelated to cystic fibrosis.

Adult↗
PubMed1983

Genetic analysis of the 15;17 chromosome translocation associated with acute promyelocytic leukemia.

Somatic cell hybrids have been constructed between a thymidine kinase-deficient mouse cell line and blood leukocytes from a patient with acute promyelocytic leukemia showing the 15q+;17q- chromosome translocation frequently associated with this disease. One hybrid contains the 15q+ translocation chromosome and very little other human material. We have shown that the c-fes oncogene, which has been mapped to chromosome 15, is not present in this hybrid and, therefore, probably is translocated to the 17q- chromosome. Analysis of the genetic markers present in this hybrid has enabled a more precise localization of the translocation breakpoints on chromosomes 15 and 17. Our experiments also have enabled an ordering and more precise mapping of several genetic markers on chromosomes 15 and 17.

Adult↗