Taxonomic group: bacteria / Firmicutes
(Phylum: Firmicutes)
Host organism: Sus scrofa
Associated disease: meningitis [ICD11:
1D01 
];
septicemia [ICD11:
MA15.Y 
];
infection due to Streptococcus suis [ICD11:
XN5SE 
]
NCBI PubMed ID: 32747605Publication DOI: 10.1128/IAI.00377-20Journal NLM ID: 0246127Publisher: American Society for Microbiology
Correspondence: Mariela Segura <mariela.segura

umontreal.ca>
Institutions: National Research Council, Ottawa, Ontario, Canada, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Gifu, Japan, Canadian Glycomics Network (GlycoNet), University of Alberta, Edmonton, AB, Canada, Swine and Poultry Infectious Diseases Research Centre, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada, Research Group on Infectious Diseases in Production Animals, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Quebec, Canada, Division of Bacterial and Parasitic Disease, National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Japan
Streptococcus suis is an encapsulated bacterium and one of the most important swine pathogens and a zoonotic agent for which no effective vaccine exists. Bacterial capsular polysaccharides (CPSs) are poorly immunogenic, but anti-CPS antibodies are essential to the host defense against encapsulated bacteria. In addition to the previously known serotypes 2 and 14, which are nonimmunogenic, we have recently purified and described the CPS structures for serotypes 1, 1/2, 3, 7, 8, and 9. Here, we aimed to elucidate how these new structurally diverse CPSs interact with the immune system to generate anti-CPS antibody responses. CPS-stimulated dendritic cells produced significant levels of C-C motif chemokine ligand 3 (CCL3), partially via Toll-like receptor 2 (TLR2)- and myeloid differentiation factor 88-dependent pathways, and CCL2, via TLR-independent mechanisms. Mice immunized with purified serotype 3 CPS adjuvanted with TiterMax Gold produced an opsonizing IgG response, whereas other CPSs or adjuvants were negative. Mice hyperimmunized with heat-killed S. suis serotypes 3 and 9 both produced anti-CPS type 1 IgGs, whereas serotypes 7 and 8 remained negative. Also, mice infected with sublethal doses of S. suis serotype 3 produced primary anti-CPS IgM and IgG responses, of which only IgM were boosted after a secondary infection. In contrast, mice sublethally infected with S. suis serotype 9 produced weak anti-CPS IgM and IgG responses following a secondary infection. This study provides important information on the divergent evolution of CPS serotypes with highly different structural and/or biochemical properties within S. suis and their interaction with the immune system.
capsular polysaccharide, immunogenicity, Streptococcus suis, Serotype 3
Structure type: polymer chemical repeating unit
Location inside paper: Fig.1, serotype 14
Compound class: CPS
Contained glycoepitopes: IEDB_130646,IEDB_130697,IEDB_135813,IEDB_136044,IEDB_136794,IEDB_137340,IEDB_137472,IEDB_137776,IEDB_140108,IEDB_140122,IEDB_141794,IEDB_141807,IEDB_142487,IEDB_142488,IEDB_146100,IEDB_146664,IEDB_149174,IEDB_151531,IEDB_158551,IEDB_190606,IEDB_548866,IEDB_548869,IEDB_983931,SB_126,SB_132,SB_165,SB_166,SB_170,SB_171,SB_172,SB_173,SB_187,SB_192,SB_195,SB_30,SB_6,SB_7,SB_84,SB_88
Methods: NanoOrange assay, chemokine production, immunogenicity studies
Related record ID(s): 3682, 3684, 3685, 3686, 3687, 3688, 32110
NCBI Taxonomy refs (TaxIDs): 1307Reference(s) to other database(s): GTC:G57867VP
Show glycosyltransferases
There is only one chemically distinct structure: