Biomedical subjects

L A Bergmeier

Publications and source records attributed to L A Bergmeier.

39 records · Page 3Linked to original sources

PubMed1980

Protein antigens of Streptococcus mutans: purification and properties of a double antigen and its protease-resistant component.

A surface protein antigen of Streptococcus mutans having two sets of antigenic determinants (antigens I and II) was purified by column chromatography from culture supernatants of S. mutans serotype c. The protease-resistant component, antigen II, was purified from pronase-digested antigen I/II. The antigens were analyzed chemically and immunologically, and their physicochemical properties were investigated. Antigen I/II consisted of more than 80% protein, and its peptide chain molecular weight was estimated to be 185,000. Antigen II consisted of approximately 60% protein, with a peptide chain molecular weight of 48,000. Antisera to antigens I/II and II were raised in rabbits and used to investigate the presence of the antigens in cells of other streptococci. This indicated that not only serotype c but also serotypes e and f possessed antigen I and II determinants, whereas serotypes a, d, and g possessed a determinant related to antigen I but not one related to antigen II.

Amino Acids↗

PubMed1980

Affinity purification and characterization of protease-susceptible antigen I of Streptococcus mutans.

An antigenic component (antigen I) of the cell surface of Streptococcus mutans has been purified from culture supernatants and shown to be immunologically identical to the protease-susceptible moiety of antigen I/II. Ion-exchange and gel filtration chromatography failed to yield a physicochemically homogeneous product. Immunoasbsorbent chromatography on single and tandem columns containing immobilized antibodies to antigens I/II and II yielded identical products which were homogeneous in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and which when injected into rabbits induced monospecific antisera to antigen I. This antigen consisted of approximately 70% protein. Its molecular weight was estimated as 150,000, and the isoelectric point was estimated to be 5.1. Immunofluorescence microscopy using monospecific antiserum to antigen I showed that a similar antigen was present on cells of S. mutans serotypes a, c, d, e, f, and g, but not b.

Animals↗

PubMed1978

Passage of immunoglobulins from plasma to the oral cavity in rhesus monkeys.

The passage of immunoglobulin from plasma to the oral cavity was studied in rhesus monkeys. Immunoglobulins G, A and M were purified from pooled rhesus monkey serum, radiolabelled with 125I and injected intravenously into twelve monkeys. Sequential samples of oral fluids were taken over a 24 h period and were assayed for radioactivity. Radioactivity could be detected in crevicular fluid washings after 0.5 h in monkeys injected with IgG and IgA, and after 2 h in monkeys given IgM. Maximal levels were found after 4 h with each immunoglobulin. Radioactivity in parotid and mixed saliva could be detected in all animals after 30 min, reaching a maximal level after 4 h. Ultracentrifugation on sucrose density gradients revealed that most of the radioactivity in crevicular fluid washings was in the 7S zone in the animals given IgG and IgA, and in a 19S zone in animals given IgM. The radioactivity in partoid saliva did not represent intact immunoglobulin molecules, since all the activity was present in zones of low molecular weight in animals given IgG, IgA or IgM. In mixed saliva a small amount of radioactivity was found in the immunoglobulin zones. The results suggest that intact molecules of IgG, IgA and IgM can pass from plasma to the oral cavity via crevicular fluid, and could contribute to oral defence mechanisms particularly in the crevicular domain. The volume of crevicular fluid in the approximal space of deciduous molars of rhesus monkeys was estimated to be approximately 0.3 microliter.

Animals↗