Search PubMed⌕ Search

Biomedical subjects

B Dietzschold

Publications and source records attributed to B Dietzschold.

At least 127 records · Page 7Linked to original sources
PubMed1984

Fine structure analysis of type-specific and type-common antigenic sites of herpes simplex virus glycoprotein D.

The fine structure of the antigenic determinants of herpes simplex virus type 1 and 2 glycoprotein D (gD) was analyzed to determine whether structural differences underlie the differential immunogenicity of these glycoproteins. A region common to herpes simplex virus type 1 and 2 gD (amino acid residues 11 to 19) and two sites specific for herpes simplex virus type 2 gD (one determined by proline at position 7, the other determined by asparagine at position 21) were localized within the N-terminal 23 amino acids of gD by synthesis of peptides and comparison of their cross-reactivity with antisera raised to herpes simplex virus type 1 and 2 gD. The secondary structure of these peptides, as predicted by computer analysis, is discussed in relation to their immunogenicity.

Amino Acid Sequence↗
PubMed1984

T cell responses to cleaved rabies virus glycoprotein and to synthetic peptides.

The antigenic structure of the rabies virus glycoprotein has been studied. A limited number of fragments were obtained by cyanogen bromide (CNBr) cleavage of viral glycoprotein, and eight large peptides were isolated by using sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. These were tested for their capacity to stimulate the proliferation of nylon wool-purified T cells obtained from spleens of rabies-immune A/J mice. Three peptides (Cr1, Cr2 plus Cr2A, and Cr3) stimulated antigen-specific proliferation, indicating that at least three T cell determinants of the native molecule are sequential or continuous in nature. Stimulation was also obtained with 27-residue and 13-residue synthetic peptides (designated R21 and R20, respectively) that included sequences towards the carboxy terminal end of Cr1, but not with synthetic peptides that included sequences of Cr2 and Cr3 (which are both glycosylated in virus-derived material). The intact viral glycoprotein and synthetic peptide R21 stimulated T lymphocytes with surface characteristics of helper cells, and induced the production of interleukin 2 by these lymphocytes. Synthetic peptides R20 and R21 also stimulated a minor population of Lyt-2-positive cells, which were not yet identified as either suppressor or cytotoxic T lymphocytes.

Animals↗
PubMed1983

Influenza virus site recognized by a murine helper T cell specific for H1 strains. Localization to a nine amino acid sequence in the hemagglutinin molecule.

The functional helper T cell line Vir-2, derived from a PR8 (H1N1) influenza virus-immunized BALB/c mouse, proliferates in response to syngeneic antigen-presenting cells and naturally occurring strains of subtype H1 human influenza virus from 1934-1957 and 1977-1980 isolates. A conserved region of the hemagglutinin molecule around amino acid position 115 in the heavy chain (HA1) was implicated as being important in this recognition by the lack of stimulatory activity associated with a glutamic acid to lysine substitution at position 115 in the laboratory mutant RV6, derived from wild-type PR8. Characterization of the stimulatory determinant on the wild-type hemagglutinin molecule was then undertaken using cleavage products and synthetic peptides. Vir-2 cells recognized the reduced and alkylated purified HA1 of PR8 virus, and this reactivity was retained after cleavage at methionine and tryptophan residues. High-pressure liquid chromatography separation of cleavage fragments indicated that a short sequence of the HA1 containing residue 115 was being recognized. This recognition was localized to a nine amino acid segment (positions 111-119) by assaying stimulation with synthetic peptide homologues of different lengths from that region. As with native hemagglutinin, Vir-2 cells responded to active peptides when presented by H-2d but not H-2k antigen-presenting cells.

Amino Acid Sequence↗
PubMed1983

Chemical and immunological analysis of the rabies soluble glycoprotein.

Soluble glycoprotein (Gs), purified from virion-depleted, rabies-infected tissue culture fluid, was chemically and immunologically analyzed. A comparison of this antigen with the virion-associated glycoprotein showed that Gs lacks 58 amino acid residues from the carboxy terminus of the virion-associated glycoprotein. Analysis with monoclonal antibodies revealed that all the epitopes of the viral glycoprotein are also present in the soluble glycoprotein. However, when tested for its ability to protect mice against a lethal challenge infection with rabies virus, Gs in contrast to viral glycoprotein, showed no protective activity. These results suggest that the carboxy terminus of the rabies virus glycoprotein is necessary for its full protective activity even though this portion of the glycoprotein molecule does not contain any antigenic determinants.

Animals↗
PubMed1983

Structural analysis of three subunits of laminin from teratocarcinoma-derived parietal endoderm cells.

The structure of the three polypeptide chains of the laminin subunits and the number of glycosylation sites in each polypeptide chain were determined using peptide mapping by high-performance liquid chromatography. Analysis of the [35S]methionine-labeled underglycosylated laminin isolated from tunicamycin (TM)-treated cells revealed that the three subunits of laminin contain unique polypeptide chains. Analysis of [3H]glucosamine-labeled glycosylated laminin subunits showed that they are sialylated and that each subunit has 11-14 glycosylation sites.

Animals↗
PubMed1983

Characterization of an antigenic determinant of the glycoprotein that correlates with pathogenicity of rabies virus.

The pathogenicity of fixed rabies virus strains for adult mice depends on the presence of an antigenic determinant on the viral glycoprotein. Two virus-neutralizing monoclonal antibodies have been used to identify this determinant. All pathogenic strains of fixed rabies virus bind to these antibodies and are neutralized by them, whereas nonpathogenic strains fail to react with these monoclonal antibodies and are not neutralized by them. Antigenic variants of the rabies virus with altered glycoprotein were selected by growing virus in the presence of one monoclonal antibody, 194-2. All variants that lost their ability to react with this antibody and an additional antibody, 248-8, were found to be nonpathogenic for adult mice. Analysis of tryptic peptides of the glycoproteins of pathogenic parent virus and nonpathogenic variants and the amino acid sequence of a specific variant tryptic peptide revealed that the change in pathogenicity corresponded to an amino acid substitution at position 333 of the glycoprotein molecule. The nucleotide sequence of the nonpathogenic variant glycoprotein gene contained a base change that confirmed the single amino acid substitution in the tryptic peptide replacing arginine-333 in the parental glycoprotein. We conclude that arginine-333 is essential for the integrity of an antigenic determinant and for the ability of rabies viruses to produce lethal infection in adult mice.

Amino Acid Sequence↗
PubMed1982

Antigenic structure of rabies virus glycoprotein: ordering and immunological characterization of the large CNBr cleavage fragments.

After rabies virus glycoprotein was treated with CNBr, the peptide mixture was fractionated by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. CNBr-cleaved peptide fragments were resolved into seven peptide bands under reducing conditions and six peptide bands under nonreducing conditions. The isolated nonreduced polypeptides were further analyzed by electrophoresis under reducing conditions. The N-terminal amino acid sequences were determined for the peptides in each of the isolated bands. The sequence data identified eight CNBr peptides and allowed the peptide fragments to be ordered within the deduced amino acid sequence of the glycoprotein. Analysis of the nonreduced CNBr peptides revealed two conformations of the glycoprotein. Two CNBr peptide fragments were specifically immunoprecipitated with a hyperimmune anti-rabies glycoprotein serum. These two and one other CNBr peptide induced the production of rabies virus-neutralizing antibodies, indicating the existence of at least three distinct antigenic sites on the rabies virus glycoprotein.

Amino Acid Sequence↗
PubMed1980

Preparation and characterization of rabies virus hemagglutinin.

Rabies virus glycoprotein, released by treatment with Triton X-100, was isoelectrically focused in a sucrose gradient containing the nonionic detergent octylglucoside. Removal of the detergent by dialysis resulted in aggregates of variable size and shape. The hemagglutinating activity of this preparation was approximately sixfold higher than that of the intact virus. The protein with hemagglutinating activity and with a buoyant density of 1.237 consisted solely of polypeptide chains of the G-protein and contained 0.38% phospholipids and 16 ng of Triton X-100 per mg of protein. In the National Institutes of Health test the hemagglutinin conferred a significantly higher protective activity than detergent-associated glycoprotein and was as effective as an inactivated virus vaccine. However, after the application of a single dose of hemagglutinin, the onset of protection was delayed by approximately 7 days when compared with inactivated virus vaccine.

Centrifugation, Density Gradient↗
PubMed1978

Isolation and purification of a polymeric form of the glycoprotein of rabies virus.

Of the three major proteins associated with the rabies virus membrane, only the glycoprotein was found to be located on the external surface of the virus membrane. Glycoprotein prepared by treatment of rabies virus with Triton X-100 and purified by isoelectric focusing was found to be homogeneous with respect to size and isoelectric point. This material, which is free of phospholipids, is able to protect in vaccination experiments against a lethal challenge infection with rabies virus. The apparent mol. wt. of this component isolated under non-denaturing conditions is approx. 400000. The same material analysed by SDS polyacrylamide gel electrophoresis (PAGE) was found to consist solely of polypeptide chains of the G protein (mol. wt. 80000). A minor glycoprotein (gp 50), detected by PAGE of the Triton X-100 released material, appeared to be a breakdown product of the G-protein. Therefore the detergent released material represents homopolymers of the G-protein. Whether the antigenic determinants reside on the monomeric subunit or are a property of the polymeric form of the G-protein is discussed.

Epitopes↗
PubMed1978

Subunit and fine structure of the glycoprotein of bovine leukemia virus.

The structure of the glycoprotein of bovine leukemia virus (BLV) was investigated. Analysis of BLV under nonreducing conditions revealed two viral glycoproteins with apparent molecular weights of 162,000 (VGP I) and 85,000 (VGP II). After reduction and alkylation, two glycosylated polypeptide chains of apparent molecular weights of 60,000 (gp 60) and 30,000 (gp 30) could be demonstrated in VGP I and VGP II; VGP I appears to contain two molecules of gp 60 and two molecules of gp 30, and VGP II consists of only one molecule of gp 60 and one molecule of gp 30 linked by disulfide bonds. Comparison of the tryptic peptides of gp 60 and gp 30 provided evidence for the existence of partial sequence relationship between gp 60 and gp 30. The structural similarity of the BLV glycoprotein molecule to immunoglobulins is discussed in regard to the possible function of this protein in the pathogenesis of bovine leukemia.

Chromatography, Ion Exchange↗
PubMed1978

Structure and function of rabies virus glycoprotein.

Of the three major proteins associated with the rabies virus membrane, only the glycoprotein (G-protein) was found to be located on the external surface of the viral membrane. A minor glycoprotein (gp 50) detected by SDS-polyacrylamide gel electrophoresis (PAGE) of rabies virus appeared to be a breakdown product of the G-protein. Glycoprotein prepared by treatment of rabies virus with Triton X100 and purified by isoelectric focusing was found to be homogeneous with respect to size and isoelectric point. The apparent molecular weight of this component isolated under nondenaturing conditions is approximately 400,000 daltons. The same material analyzed by PAGE was found to be comprised solely of polypeptide chains of the G-protein (MW 80,000 daltons). Therefore, the Triton X100-released material represents homopolymers of the G-protein. The purified rabies virus glycoprotein (G) is only structural protein of the virus that induces the formation of virus-neutralizing antibodies and which confers immunity to animals. The total protective activity of the virus was recovered in the purified G protein preparation. The protective activity of G protein increased with purification : 9 ng of G protein was required to protect 50% of the mice as compared to 1.63 microgram of the virus. The number of oligosaccharide side chains on rabies virus glycoprotein was investigated. Analysis of glycopeptides obtained by protease digestion of desialated glycoprotein revealed three discrete glycopeptides. Comparison of the protease digestion products from desialated and from untreated glycoprotein indicated a heterogeneity among the glycopeptides in the sialic acid content. Two major tryptic glycopeptides were isolated from desialated rabies virus glycoprotein and were analyzed after protease digestion; one contained two oligosaccharide side chains and the other contained a single oligosaccharide side chain.

Chemical Phenomena↗
PubMed1977

Comparison of the ribonucleoproteins of different rabies virus serotypes by radioimmunoassay.

Radioimmunoassay (RIA) provides a sensitive serological procedure for detecting rabies virus ribonucleoprotein (RNP) as well as its specific antibodies, RIA was carried out using highly purified RNPs labelled by the chloramine-T method. This paper describes optimal conditions for iodination of RNP with high specific activity. The optimal concentrations of 125I, RNP, chloramine-T, and reducing agent as well as the effect of pH on the reaction were investigated. RIA proved to be extremely sensitive for detection of homologous antibodies. In competition experiments the part-relationship of the group-specific RNPs of the three rabies virus serotypes (HEP, MOK and LBV) was confirmed.

Chloramines↗