title: Streptococcal growth and toxin production in vivo.
abstract: Streptococcal growth in vivo was studied with inoculated micropore filter chambers which were implanted into the peritoneal cavities of mice. Eight of nine group A strains and one group B strain grew in vivo, achieving concentrations of 10(7) to 10(9) CFU/ml in the chambers. Experiments with the Richards strain showed that the number of viable organisms remained high at 5 and 8 weeks after infection. The use of specific inhibitors and appropriate toxin-negative strains demonstrated that both cytolytic toxins produced by group A streptococci, streptolysin S and streptolysin O, were present in the culture fluids harvested from the chambers. This finding represents the first evidence that streptolysin S is produced in vivo. The host response to streptococci growing in vivo was examined by following the increase in serum antistreptolysin O levels. The response was first detected 2 weeks after chamber implantation and appeared to be maximal after 5 weeks. In addition, the production of antibody to streptococcal cell surface antigens was demonstrated indirectly with fluorescein-labeled anti-mouse immunoglobulin G.
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D001202:Ascitic Fluid / Q000382:microbiology; D001427:Bacterial Toxins / Q000096:biosynthesis*; D051379:Mice; D013290:Streptococcal Infections / Q000276:immunology; D013291:Streptococcus / Q000254:growth & development*
chemical_list: D000907:Antibodies, Bacterial; D001427:Bacterial Toxins