title: The protective protein Sao (surface antigen one) is not a critical virulence factor for Streptococcus suis serotype 2.
abstract: Surface antigen one (Sao) is protein that was shown to protect pigs in vaccination trials against disease caused by Streptococcus suis. Here, we used an isogenic Δsao mutant to investigate the insofar unknown role of Sao in S. suis virulence. The Δsao mutant and its wild-type parent strain (sequence type 1, European strain) did not present significant differences on levels of adhesion/invasion of swine respiratory epithelial cells. Moreover, the Δsao mutant resisted phagocytosis by macrophages similarly to the parent strain and it was still virulent in a mouse model of infection. Our findings suggest a minor role of Sao in S. suis serotype 2 virulence.
authors: Faculté de médecine vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada J2S 2M2.
authors: David
authors: D
authors: Roy
authors: Public Health Ontario, 81 Resources Road, Toronto, Ontario, Canada M9P 3T1.
authors: Nahuel
authors: N
authors: Fittipaldi
authors: Faculté de médecine vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada J2S 2M2.
authors: Audrey
authors: A
authors: Dumesnil
authors: Faculté de médecine vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada J2S 2M2.
authors: Sonia
authors: S
authors: Lacouture
authors: Faculté de médecine vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada J2S 2M2. Electronic address: marcelo.gottschalk@umontreal.ca.
authors: Marcelo
authors: M
authors: Gottschalk
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology*; D005260:Female; D008264:Macrophages / Q000276:immunology; D008297:Male; D051379:Mice; D010587:Phagocytosis; D013290:Streptococcal Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D017011:Streptococcus suis / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity; D013552:Swine; D013553:Swine Diseases / Q000276:immunology / Q000382:microbiology*; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D037521:Virulence Factors
keywords: Adhesion/invasion epithelial cells; Phagocytosis; Serotype 2; Streptococcal antigen one (Sao); Streptococcus suis; Virulence factor