Skip to Content
MilliporeSigma
  • Enterococcus faecalis capsular polysaccharide serotypes C and D and their contributions to host innate immune evasion.

Enterococcus faecalis capsular polysaccharide serotypes C and D and their contributions to host innate immune evasion.

Infection and immunity (2009-10-07)
Lance R Thurlow, Vinai Chittezham Thomas, Sherry D Fleming, Lynn E Hancock
ABSTRACT

It has become increasingly difficult to treat infections caused by Enterococcus faecalis due to its high levels of intrinsic and acquired antibiotic resistance. However, few studies have explored the mechanisms that E. faecalis employs to circumvent the host innate immune response and establish infection. Capsular polysaccharides are important virulence factors that are associated with innate immune evasion. We demonstrate, using cultured macrophages (RAW 264.7), that capsule-producing E. faecalis strains of either serotype C or D are more resistant to complement-mediated opsonophagocytosis than unencapsulated strains. We show that differences in opsonophagocytosis are not due to variations in C3 deposition but are due to the ability of capsule to mask bound C3 from detection on the surface of E. faecalis. Similarly, E. faecalis capsule masks lipoteichoic acid from detection, which correlates with decreased tumor necrosis factor alpha production by cultured macrophages in the presence of encapsulated strains compared to that in the presence of unencapsulated strains. Our studies confirm the important role of the capsule as a virulence factor of E. faecalis and provide several mechanisms by which the presence of the capsule influences evasion of the innate immune response and suggest that the capsule could be a potential target for developing alternative therapies to treat E. faecalis infections.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
o-Phenylenediamine dihydrochloride, peroxidase substrate
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 3 mg substrate per tablet
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 60 mg substrate per tablet
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 10 mg substrate per tablet
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 5 mg substrate per tablet
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 4 mg substrate per tablet
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 15 mg substrate per tablet
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 5 mg substrate per tablet
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 2 mg substrate per tablet
Sigma-Aldrich
m-Phenylenediamine dihydrochloride, ≥99.0% (AT)
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 30 mg substrate per tablet
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 1 mg substrate per tablet
Sigma-Aldrich
o-Phenylenediamine dihydrochloride, tablet, 20 mg substrate per tablet
Sigma-Aldrich
1,4-Phenylenediamine dihydrochloride, ≥99.0%
Sigma-Aldrich
Lipopolysaccharides from Salmonella enterica serotype typhimurium, suitable for cell culture, BioXtra, γ-irradiated
Sigma-Aldrich
Lipopolysaccharides from Salmonella enterica serotype typhimurium, purified by trichloroacetic acid extraction
Sigma-Aldrich
Lipopolysaccharides from Salmonella enterica serotype typhimurium, purified by gel-filtration chromatography
Sigma-Aldrich
Lipopolysaccharides from Salmonella enterica serotype typhimurium, purified by phenol extraction