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E J Aitchison

Publications and source records attributed to E J Aitchison.

5 recordsLinked to original sources
PubMed1990

Effect of in vivo growth conditions upon expression of surface protein antigens in Enterococcus faecalis.

Western blotting of whole-cell preparations of Enterococcus faecalis showed the protein-antigen profiles to be markedly influenced by growth conditions. The E. faecalis-specific antigens of 40 and 37 kDa, which are prominent in endocarditis, were strongly expressed following growth in serum or brain heart infusion, but not after growth in a chemically defined medium. The expression of these antigens in vivo was demonstrated in cells grown as a biofilm on silastic discs in the peritoneum of rabbits. These in vivo culture conditions may be useful in studying the pathogenesis of E. faecalis infections and the effectiveness of antibiotic therapy.

Animals↗
PubMed1990

Serological response in Enterococcus faecalis endocarditis determined by enzyme-linked immunosorbent assay.

Enterococcus (Streptococcus) faecalis expresses three species-specific surface protein antigens of molecular weights 73,000, 40,000, and 37,000. On Western blotting (immunoblotting), they were detected strongly by immunoglobulin G (IgG) in sera from patients with E. faecalis endocarditis, but not in sera from patients with other E. faecalis infections or with endocarditis due to other streptococci. We developed an enzyme-linked immunosorbent assay system to measure IgG, IgM, and IgA levels to these antigens and evaluated its potential as a serodiagnostic test for E. faecalis endocarditis. The test correctly diagnosed E. faecalis endocarditis in 15 of 16 cases. Of 10 cases of endocarditis due to other streptococci and 10 E. faecalis infections other than endocarditis, 9 and 8, respectively, gave negative results. The test should prove particularly useful in culture-negative cases, for which choice of appropriate antibiotic therapy for E. faecalis endocarditis is vital.

Antibodies, Bacterial↗
PubMed1987

Serodiagnosis of Streptococcus faecalis endocarditis by immunoblotting of surface protein antigens.

We describe a method for the serodiagnosis of Streptococcus faecalis in infective endocarditis which could be of value in culture-negative cases. Serum-grown cells of S. faecalis produced three major characteristic protein antigens (73,000, 40,000, and 37,000 molecular weight) which were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of solubilized whole cells. After electrophoretic transfer to a nitrocellulose membrane, these antigens were visualized by probing with serum from patients with endocarditis caused by S. faecalis. Serum from patients with endocarditis caused by other organisms did not react with the S. faecalis-specific antigens. This procedure should facilitate positive early diagnosis of S. faecalis endocarditis or establish its absence in culture-negative cases.

Antibodies, Bacterial↗
PubMed1986

Antigenic composition of an endocarditis-associated isolate of Streptococcus faecalis and identification of its glycoprotein antigens by ligand blotting with lectins.

The antigenic composition of an endocarditis-associated isolate of Streptococcus faecalis was studied by immunoblotting of whole cells and cell walls from sodium-dodecyl sulphate polyacrylamide gels on to nitrocellulose and detection with serum from patients and hyperimmune rabbit serum. A major envelope protein antigen of mol. wt 53 X 10(3) detected with patient's serum was also present in three urinary strains of Str. faecalis and a laboratory strain of Str. faecalis ss. zymogenes but not in Staphylococcus aureus. Other common antigens of Str. faecalis were of mol. wt (10(3)) 65, 63, 56, 49.5, 30 and 21. Two other protein antigens (43 and 37 X 10(3) mol. wt) reacted strongly with asparagus pea lectin-peroxidase conjugate indicating the presence of fucosyl residues. Other lectin-peroxidase conjugates were used to demonstrate the presence of various glycosyl residues on envelope proteins. Growth of Str. faecalis in serum to mimic in-vivo growth conditions in endocarditis infections dramatically altered the antigenic patterns. Only two major antigens of mol. wt (10(3)) 56 and 53 reacted with sera from endocarditis patients. These antigens may, therefore, be of diagnostic or protective potential.

Antigens, Bacterial↗