An NLRP3 inflammasome-triggered cytokine storm contributes to Streptococcal toxic shock-like syndrome (STSLS)
Fig 6
The high membrane perforation activity of S. suis was required for STSLS.
Mice were infected with S. suis epidemic strain SC-19 or the mutant [msly (P353L)] containing the point substitution P353L, which lacks hemolytic activity. (A) Cytokine levels in peritoneal lavage fluids at 3.5 or 6 h post-infection were detected using ELISA kits (two-tailed, unpaired t-tests, n = 5). (B) Blood values of AST, ALT, LDH and CK at 6 h post-infection (two-tailed, unpaired t-tests, n = 5). (C) The bacterial load in the blood at 3.5 or 6 h post-infection was detected (two-tailed, unpaired t-tests, n = 5). (D) H&E staining of infected tissue sections from mice at 6 h post-infection with S. suis epidemic strain SC-19 or mutant [msly (P353L)]. Congestion in the lung and spleen is indicated by a “red arrow”, infiltration of inflammatory cells in the lung is indicated by a “hollow arrow”, vacuolated degeneration in the liver is indicated by a “black arrow”, and necrosis in the liver is indicated by a “yellow arrow”. (E) Clinical signs of mice infected with S. suis were monitored and scored (two-way RM ANOVA, n = 10). (F) Survival of mice infected with S. suis strains (log-rank test, n = 10). Error bars represented the mean ± standard deviations.