Differences in potency of intravenous polyspecific immunoglobulin G against streptococcal and staphylococcal superantigens: implications for therapy of toxic shock syndrome.
Administration of intravenous polyspecific immunoglobulin G (IVIG) has been proposed as adjunctive therapy for toxic shock syndrome caused by Streptococcus pyogenes or Staphylococcus aureus. We investigated whether superantigen-containing culture supernatants prepared from streptococcal isolates (n=21) and staphylococcal isolates (n=20) from cases of severe sepsis were inhibited to an equal extent by IVIG in proliferation experiments that used human peripheral blood mononuclear cells. All 3 IVIG preparations tested were highly efficient in neutralizing the superantigens, and most supernatants were completely inhibited at concentrations ranging from 0.05 to 2.5 mg IVIG/mL. An important finding was that culture supernatants from S. pyogenes isolates were consistently inhibited to a greater extent than those of S. aureus isolates (P<.01). The findings demonstrate that staphylococcal superantigens are not inhibited as efficiently as streptococcal superantigens by IVIG, and, hence, a higher dose of IVIG may be required for therapy of staphylococcal toxic shock syndrome in order to achieve protective titers and clinical efficacy.
Darenberg
Jessica
J
Karolinska Institutet, Center for Infectious Medicine, Department of Medicine, Huddinge University Hospital, Stockholm, Sweden.
Söderquist
Bo
B
Normark
Birgitta Henriques
BH
Norrby-Teglund
Anna
A
D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000276:immunology / Q000627:therapeutic use*; D012703:Serotyping; D012772:Shock, Septic / Q000276:immunology / Q000382:microbiology / Q000628:therapy*; D013211:Staphylococcus aureus / Q000145:classification / Q000276:immunology; D013290:Streptococcal Infections / Q000276:immunology / Q000628:therapy*; D013297:Streptococcus pyogenes / Q000145:classification / Q000276:immunology; D018089:Superantigens / Q000276:immunology*
D016756:Immunoglobulins, Intravenous; D018089:Superantigens