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Biomedical subjects

B Wagner

Publications and source records attributed to B Wagner.

At least 271 records · Page 15Linked to original sources
PubMed1978

An electron microscopic study of the location of peptidoglycan in group A and C streptococcal cell walls.

The morphological appearance of deproteinized Group A and C streptococcal walls after treatment by different procedures extracting teichoic acids and polysaccharides (formamide, hydrochloric acid, nitrous acid, trichloroacetic acid, sulphuric acid, sodium hydroxide and sodium deoxycholate) was compared with the content of teichoic acids and polysaccharides remaining in the treated walls. All procedures extracted teichoic acids almost completely, but polysaccharides were extracted to various degrees. The ultrastructural appearance of walls after these extractions still exhibited the triple-layered wall profile; only a reduction of thickness of the wall and of electron density of the layers occurred. There was no direct correlation between the reduction of rhamnose content and thickness of walls. The ultrastructural localization of peptidoglycan in the streptococcal walls was explored by means of the indirect immunoferritin technique using anti-peptidoglycan antibodies isolated from anti-Group A-variant antisera. Ferritin particles were bound predominantly to filamentous structures which protruded from both surfaces of peptidoglycan fragments and isolated walls. Peptidoglycan was also detected on the filamentous protrusions of whole cocci. These results contradict models of the streptococcal wall in which peptidoglycan forms the innermost layer and support a mosaic structure in which peptidoglycan forms a network of the peptidoglycan-polysaccharide complex.

Antibodies, Bacterial↗
PubMed1978

The use of lysozyme-peroxidase-conjugates for the electron microscopic detection of peptidoglycan in the cell wall of streptococci.

Conjugation of lysozyme with horse radish peroxidase by means of glutaraldehyde results in a complex which retains the activities of both enzymes. The incubation of peptidoglycan with lysozyme-peroxidase followed by the reaction with 3,3'-diaminobenzidine and H2O2 results in a strong labelling of both sides. In contrast, after treatment with peroxidase alone no reaction was observed. Thus, the specific binding of lysozyme-peroxidase can be used for the electron microscopic localization of this component in the bacterial cell wall. Isolated peptidoglycane as well as trypsinized cell walls of group A and C streptococci were labelled both on the inner and the outer surface. The surface of intact cells of group A- and C-streptococci was labelled only sparsely. In contrast, by means of the indirect immunoferritin technique strong labelling of intact cells was effected with specific anti-peptidoglycan antibodies. The specificity of these antibodies are mainly directed to the peptide side chains. From this we suggest that in the cell wall of group A and C streptococci the lysozyme-sensitive part of the peptidoglycan is not so superficially localized as the peptides.

Cell Wall↗
PubMed1978

[The localization of the anodically-moving thermolabile antigen (ATA) of gram-negative bacteria with ferritin-labelled antibodies (author's transl)].

In studies on the antigenic structure of shigellae, an anodically-moving thermolabile antigen (ATA) was found, which furthermore could be detected in many other enterobacteriae (9, 10). ATA is a glycoprotein with a high molecular heterogeneity, resulting from aggregates of a subunit with a molecular weight of about 22000 Daltons. In the present paper the antigen was localized on the cell surface of several species by means of the immunoferritin technique. Antibodies against the purified ATA were raised in rabbits and were coupled with ferritin using glutaraldehyde. The antigen was found focally distributed over the whole circumference of the cell. According to the location of the ferritin granules, the ATA is tightly attached to the outer membrane. Especially some rough forms of the bacteria were heavily labelled on their surface. From the results obtained we conclude that in the smooth form the polysaccharide side chains of the somatic antigen cover the ATA.

Antibodies, Bacterial↗
PubMed1978

[Agglutinins in marine brown algae. Dedicated to Professor Dr. H. Knöll on his 65th birthday].

Extracts from the brown algae Fucus vesiculosus, F. serratus, and Halidrys siliquosa agglutinated human erythrocytes of groups A, B, O, and AB as well as erythrocytes from some animal species, ascites tumour cells from mice, and streptococci of many groups of the LANCEFIELD system. The extract of Chorda filum did not show haemagglutination but agglutinated ascites tumour cells and streptococci of a few groups.

ABO Blood-Group System↗
PubMed1978

[Use of ferritin conjugates of a lectin from mistletoe (Viscum album L.) for the electron microscopic localization of cell surface receptors].

Ferritin conjugates of a lectin from mistletoe (Viscum album L.) were used for the electron-microscopic demonstration of carbohydrate receptors on the cell surface of human erythrocytes and murine tumor cells. Human A1 erythrocytes showed only a slight focal binding of ferritin. Cells of the mouse ascites tumor strain L 1210 were labelled very tightly on their surface and incorporate the ferritin by pinocytosis. Furthermore they showed cytotoxic changes in their ultrastructure. In the presence of galactose the labelling on the surface, the incorporation of the conjugate within the cell as well as the cytotoxicity were inhibited.

Animals↗
PubMed1977

Immunoferritin studies on the multiplication of Sindbis virus in chick embryo fibroblasts.

Replication of Sindbis virus chick embryo fibroblasts was studied by means of the immunoferritin technique. Virus specific antigens, diffusely distributed in the cytoplasm, were observed at first 3 hours p.i. At the same time in ohter cells ferritin particles in linear arrangement occured at the surface of vesicles. At these places heavily labelled nucleocapsids were observed later on. This means, that the surface of vesicles is a site of assembly of nucleocapsids. Maturation of virus takes place at the cell surface as well as at the vesicles by budding. In early stages of replication maturation at the membrane prevalis.

Animals↗
PubMed1977

Electron microscopic detection of the cryptantigen AhumHP (Friedenreich antigen) on human erythrocytes by means of gold-labelled agglutinin from Helix pomatia.

Using the gold-labelled agglutinin anti-AHP from Helix pomatia (edible snail) the ultrastructural site and distribution of the cryptantigen (Friedenreich antigen) AhumHP was revealed on neuraminidase treated human O and B erythrocytes. On A1 and A2 cells the antigen was demonstrated simultaneously with the blood group antigen A by labelling the cells with anti-AHP-ferritin followed by removing the neuraminic acid and labelling with anti-AHP-gold. The cryptantigen is focally distributed on the cell surface.

Agglutinins↗
PubMed1976

[Electron microscopic detection of blood group antigen A on human erythrocytes by means of ferritin- and gold-labelled protectin of helix pomatia].

By means of ferritin- and gold-labelled protectin from the albumen gland of the edible snail Helix pomatia the blood group antigen A was located on human erythrocytes of groups A1, A2 and A1B. With erythrocytes of groups O and B the reaction is negative. The antigen is focally distributed on the outer surface of the cell membrane. Cells from groups A1 and A1B have an antigen A concentration about 4 times greater than A2 cells. The numbers of particles after tagging with ferritin or gold are comparable. The gold particles show an extremely high contrast and are therefore very suitable for the immunoelectron microscopic localization of antigens.

ABO Blood-Group System↗