Exacerbated Type II Interferon Response Drives Hypervirulence and Toxic Shock by an Emergent Epidemic Strain of Streptococcus suis

• Autores: Lachance, Claude; Gottschalk, Marcelo; Pereyra Gerber, Federico Pehuén; Lemire, Paul; Xu, Jianguo; Segura, Mariela
• Año de publicación: 2013
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Streptococcus Suis; Interferon Gamma; Toxic Shock; Host Response to Pathogens
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Streptococcus suis, a major porcine pathogen, can be transmitted to humans and cause severe symptoms. A large human outbreak associated with an unusual streptococcal toxic shock-like syndrome (STSLS) was described in China. Albeit an early burst of proinflammatory cytokines following Chinese S. suis infection was suggested to be responsible for STSLS case severity, the mechanisms involved are still poorly understood. Using a mouse model, the host response to S. suis infection with a North American intermediately pathogenic strain, a European highly pathogenic strain, and the Chinese epidemic strain was investigated by a whole-genome microarray approach. Proinflammatory genes were expressed at higher levels in mice infected with the Chinese strain than those infected with the European strain. The Chinese strain induced a fast and strong gamma interferon (IFN-γ) response by natural killer (NK) cells. In fact, IFN-γ-knockout mice infected with the Chinese strain showed significantly better survival than wild-type mice. Conversely, infection with the less virulent North American strain resulted in an IFN-β-subjugated, low inflammatory response that might be beneficial for the host to clear the infection. Overall, our data suggest that a highly virulent epidemic strain has evolved to massively activate IFN-γ production, mainly by NK cells, leading to a rapid and lethal STSLS.
Fil: Lachance, Claude. University Of Montreal; Canadá
Fil: Gottschalk, Marcelo. University Of Montreal; Canadá
Fil: Pereyra Gerber, Federico Pehuén. University Of Montreal; Canadá. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina
Fil: Lemire, Paul. University Of Montreal; Canadá
Fil: Xu, Jianguo. Chinese Center For Disease Control And Prevention; China
Fil: Segura, Mariela. University Of Montreal; Canadá