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Biomedical subjects

N Koide

Publications and source records attributed to N Koide.

At least 163 records · Page 9Linked to original sources
PubMed1983

Hepatocyte plasma membrane antigens. II. Characterization of liver-specific membrane lipoprotein (LP-1) and Tamm-Horsfall glycoprotein (THGP) like antigens (hepatic THGP) on the plasma membrane of Chang liver cell.

Radioiodinated cell-surface antigens of Chang liver cells recognized with anti-liver-specific membrane lipoprotein (anti-LP-1) and anti-Tamm-Horsfall glycoprotein (anti-THGP) rabbit antibodies were analyzed by the immunoprecipitation followed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The analysis revealed that the antigens precipitated with anti-LP-1 were heterogeneous in molecular species consisting of 2 major and 5 minor polypeptides with molecular weights ranging from 36 X 10(3) (36 K) to 250 K daltons. That with anti-urinary THGP was a single polypeptide with a molecular weight of 67 K daltons, which was different from urinary THGP in molecular size, and was designated hepatic THGP.

Antigens, Neoplasm↗
PubMed1983

The Epstein-Barr virus receptor is distinct from the C3 receptor.

Polyvalent serum directed against C3 receptors was employed in an attempt to block Epstein-Barr virus (EBV) binding to virus receptor-containing cell lines. The serum eliminated 90% of virus binding to Daudi and BJAB, lines which express only the C3d receptor. Raji and Ramos cells, which express the C3d, C3b and C3bi receptors, still adsorbed 70% of their virus capacity in the presence of excess antiserum. These effects were independent of the virus strain. In the light of previous reports, these data imply that, although the two receptors, EBV and C3d, are closely associated, the binding sites of EBV and complement are distinct. Additionally, an unusual EBV substrain-specific receptor found on U698 and P3HR-1/ASNP lines was shown to be independent of complement receptors.

Animals↗
PubMed1982

Truncated mu chain in a Burkitt lymphoma line (P3HR-1) and its fate in various hemapoietic somatic cell hybrids.

Hybrids obtained by the fusion of PUT, an ouabain and TG-resistant subline of the Burkitt lymphoma(BL)-derived P3HR-1 line, with hemopoietic cells of various differentiation types were tested for their membrane and intracellular immunoglobulin expression. PUT cells carry no membrane immunoglobulin, but contained intracellular 61K mu chain and kappa chain. The PUTKO-1 hybrid, derived from the fusion of PUT with the erythroleukemia line K562 contains no detectable immunoglobulin. NAMPUT, a hybrid between PUT and the IgM-lambda-producing BL line Namalwa, synthetizes cellular mu, lambda and kappa chains, but its surface-Ig is exclusively mu-lambda. Two different mu chains could be detected, both precipitated by either anti-mu or anti-lambda sera. Immunoprecipitation with anti-kappa precipitated neither kappa nor mu. PUTRAL was derived by fusing PUT with Rael, an unusual surface-IgG-lambda-carrying BL line. In this hybrid, the ability to synthesize gamma and lambda chains has been eclipsed, but two mu chains are present: one corresponding to the truncated 61K chain of PUT, and a normal-sized 74K. Between 20 and 30% of the cells stain for surface IgM.

Autoradiography↗
PubMed1982

Two large virion envelope glycoproteins mediate Epstein-Barr virus binding to receptor-positive cells.

The four major Epstein-Barr virion envelope components were separated by column chromatography and reconstituted into artificial liposomes. These liposomes were tested for their ability to bind selectively to Epstein-Barr virus receptor-positive cells. Only when the two high-molecular-weight glycoproteins, VE1 and VE2, were present together was a stable binding complex formed. The addition of the other virion envelope components did not increase the levels of binding. This binding was inhibited by unlabeled viable virions and by neutralizing antisera, which recognized the two components. Adsorption of viable virus was also eliminated by the antisera. The enzyme susceptibility pattern of the cell-liposome interaction is similar to that of the virus-cell interaction, thus confirming the specificity of the binding site. A model for Epstein-Barr virus binding in which VE1 and VE2 coordinately recognize the same binding site is presented.

Antibodies, Viral↗
PubMed1981

Difference in viral binding between two Epstein-Barr virus substrains to a spectrum of receptor-positive target cells.

Radio-labelled Epstein-Barr virus (EBV) was utilized in a direct binding assay to detect the presence of EBV receptors. The sensitivity of this method was affirmed by the detection of EBV-receptors on three EV-carrying cell lines that have previously been reported as receptor negative. Two laboratory substrains of EBV, derived from the cell lines B95-8 and P3HR-I (designated B and P virus respectively), were tested in the binding assay. The main repcptor prototype adsorbed both viral strains without apparent distinction. In contrast, two lines, a Swedish EBV-negative B-cell lymphoma (U698) and a virus non-producer subline of the receptor-negative P3HR-1 line, adsorbed P virus selectively but failed to adsorb B virus.

Binding, Competitive↗
PubMed1981

Membrane-bound and cellular immunoglobulins in human B-lymphoma lines and derived hybrids.

Hybrids derived from the fusion of cell lines representing different maturation stages were studied for their membrane and cellular immunoglobulin expression. The hybrids can be subdivided into 3 groups, with one common parental line in each group. In the first group, Raji cells represent the common parent: it contains small amounts of membrane and cytoplasmic mu (mu) and kappa (kappa) chains. In the second group, PUT is the common parent, an ouabain and TG-resistant subline of the BL-derived P3HR-1 line. PUT contains a truncated intracellular mu chain. The third group consists of hybrids between K562, an EBV-negative human erythroleukemia line and 2 different BL lines. Membrane-immunoglobulin expression was intermediate between the parental lines in the first two groups derived from the fusion of 2 BL lines. In the third group, hybridization with the K562 cell suppressed the membrane-Ig expression of the B-cell partner. Total cellular immunoglobulin determinations showed that some cells synthesized light chains in excess of heavy chains, others contained an excess of heavy chains, while still others had equal amounts of heavy and light chains. The hybrids showed a variety of patterns, including amplification of the parental phenotypes, appearance of new phenotypic combinations, and eclipse of one or both parental phenotypes. A comparison of the total and the membrane-associated immunoglobulin patterns suggests independent handling of intracellular and membrane immunoglobulin synthesis.

B-Lymphocytes↗
PubMed1981

Giant axonal neuropathy: report of two siblings with endocrinological and histological studies.

Giant axonal neuropathy in two siblings was reported. The fact that two cases are found in the same family supports this disorder is genetically determined and recessively inherited. These two cases, similar to the cases reported in literature, had chronic peripheral neuropathy and CNS symptoms, and also petit mal absence and mental retardation in elder sister (case 1) and precocious puberty in younger sister (case 2). Sural nerve biopsies in both cases disclosed axonal swellings or giant axons filled with aggregated neurofilaments, and that aggregated intermediate-sized filaments were found within cytoplasm of Schwann cells, endothelial cells of intra and extra-neurial capillaries and of extra-neurial arterioles, perineurial cells and endoneurial fibroblasts. Skin biopsies in both cases disclosed that aggregated intermediate-sized filaments were also found within cytoplasm of fibroblasts, Langerhans' cells, melanocytes and endothelial cells of capillaries, lymphatic vessels and arterioles. The diagnosis of giant axonal neuropathy can be made only by the findings in skin biopsy.

Adolescent↗
PubMed1981

The detection of Epstein-Barr virus receptors utilizing radiolabelled virus.

Epstein-Barr virus (EBV) was labelled with 3H-thymidine and purified about 1000-fold from the culture medium by ultracentrifugation on 5 to 30% dextran gradients. The presence of the virus was monitored by radioactivity and Epstein-Barr virus-determined nuclear antigen (EBNA) induction in sensitive indicator cells (Ramos). Peaks for both activities occurred in the 17 to 18% dextran fractions. Unlabelled virus recovered in the peak fraction was labelled with 125I. Both thymidine and 125I-labelled purified virus bound quantitatively to receptor-positive Burkitt lymphoma-derived cell lines but not to EBV-receptor-negative T-lymphocyte-derived cell lines. Thymidine-labelled virus that was allowed to bind to Raji cells was present in the interior of briefly trypsinized cells after 3 h incubation at 37 degrees C. The results provide a convenient method for detecting the EBV receptor by radioactively labelled virus.

Burkitt Lymphoma↗
PubMed1981

Cell surface glycoprotein patterns of two EBV-negative lines and their EBV converted sublines.

Cell surface galactosyl-glycoprotein patterns were compared between Ramos and BJAB, two Epstein-Barr virus (EBV)-negative Burkitt lymphoma lines, and their acutely EBV-superinfected and stably EBV-converted derivatives. A major difference between Ramos and its EBV-infected variants was the appearance of a 69,000 mol. wt. galactosyl-glycoprotein (GP69) in the latter. The same phenomenon was found in BJAB along with the additional appearance of a 71,000 mol. wt. galactosyl-glycoprotein (GP71) in the EBV-infected cells. GP71 was present in Ramos and in its EBV-converted derivatives.

Burkitt Lymphoma↗
PubMed1981

Cell-surface immunoglobulin and insulin receptor expression in an EBV-negative lymphoma cell line and its EBV-converted sublines.

Membrane Ig and insulin receptors were assayed in the EBV-negative Ramos lymphoma line and its EBV-converted sublines by surface fluorescence. 125I-protein A-binding assay, immunoprecipitation, and insulin receptor assay. The original Ramos line expressed surface IgM but not IgD and had a low concentration of insulin receptors. Ten of 10 converted lines expressed IgD and a variable but usually high insulin-binding capacity. Molecular weight analysis of immunoprecipitated Ig showed the presence of 2 mu-chains and 2 delta-chains. One of each heavy chain type could be characterized as membrane Ig, whereas the other was cytoplasmic. Antisera against the lambda-chain precipitated mu and delta heavy chains as well, indicating that the delta-chain expressed on the membrane of the EBV-converted Ramos lines is bound to the lambda light chain. The results show that the differentiation of a Burkitt lymphoma line is not completely "frozen" and can be induced to change in a more "activated" direction by EBV conversion.

Binding Sites↗
PubMed1978

Further studies on endo-beta-N-acetylglucosaminidase D1.

The purification procedure for endo-beta-N-acetylglucosaminidase D was improved to yield an enzyme preparation which was homogeneous upon gel electrophoresis. The molecular weight of the enzyme as estimated by Sephadex G-200 column chromatography was 280,000, while SDS-gel electrophoresis after reduction with 2-mercaptoethanol gave a value of 150,000. The purified enzyme did not show any chitinase, hyaluronidase or lysozyme activity. In the presence of exoglycosidases removing peripheral sugars, the endoglycosidase acted on serum glycoproteins such as transferrin and fetuin. The enzyme also hydrolyzed an oligosaccharide, (Man)5(GlcNAc)2, indicating that the peptide portion of substrates does not have much effect on susceptibility to the enzyme.

Acetylglucosaminidase↗
PubMed1977

Role of hydrophobic interaction in hapten-antibody binding.

The precipitation reaction of bovine serum albumin coupled with p-azophenylleucine with homologous antibody was inhibited by several structurally related haptens. The isobutyl group substituent on alpha-carbon atom of the leucine residue contributed more than -5.8 Kcal/mol to the free energy of binding. This value was consistent with the free energy change expected from the transfer of n-butane from an aqueous environment to liquid n-butane. The observed contribution was explained, in terms of the hydrophobic interaction of the isobutyl group with the antigen binding site of the antibody molecule. These results were also compared with other hapten-antibody systems.

Animals↗