title: Antiphagocytic function of an IgG glycosyl hydrolase from Streptococcus equi subsp. equi and its use as a vaccine component.
abstract: EndoSe from Streptococcus equi subsp. equi is an enzyme hydrolyzing glycosyl groups on IgG, analogous to EndoS from Streptococcus pyogenes. We here show that the activity of EndoSe leads to an antiphagocytic function and may thus be a contributory factor to immune evasion of S. equi. Despite the damaging effect that EndoSe has on IgG, antibodies against EndoSe can neutralize its function. Antibodies against EndoSe restored the opsonic activity of specific opsonizing antibodies. Mice infected with either S. equi subsp. equi or subsp. zooepidemicus or S. pyogenes could be protected by vaccination with EndoSe. It is speculated that EndoSe could be a suitable vaccine candidate against streptococcal infections.
authors.affiliation: Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden. jan-ingmar.flock@ki.se
authors.forename: Margareta
authors.initials: M
authors.lastname: Flock
authors.forename: Lars
authors.initials: L
authors.lastname: Frykberg
authors.forename: Markus
authors.initials: M
authors.lastname: Sköld
authors.forename: Bengt
authors.initials: B
authors.lastname: Guss
authors.forename: Jan-Ingmar
authors.initials: JI
authors.lastname: Flock
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000737:chemistry; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001428:Bacterial Vaccines / Q000276:immunology; D003001:Cloning, Molecular; D005260:Female; D005353:Fibronectins / Q000737:chemistry; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D006026:Glycoside Hydrolases / Q000235:genetics / Q000378:metabolism*; D007074:Immunoglobulin G / Q000378:metabolism*; D051379:Mice; D010586:Phagocytes / Q000276:immunology*; D011485:Protein Binding; D013290:Streptococcal Infections / Q000382:microbiology / Q000517:prevention & control*; D018502:Streptococcus equi / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D005353:Fibronectins; D007074:Immunoglobulin G; D006026:Glycoside Hydrolases