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.
Karolinska Institutet, Center for Infectious Medicine, Department of Medicine, Huddinge University Hospital, Stockholm, Sweden.
Jessica
J
Darenberg
Bo
B
Söderquist
Birgitta Henriques
BH
Normark
Anna
A
Norrby-Teglund
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