Involvement of enterotoxins G and I in staphylococcal toxic shock syndrome and staphylococcal scarlet fever

Abstract

We investigated the involvement of the recently described staphylococcal enterotoxins G and I in toxic shock syndrome. We reexamined Staphylococcus aureus strains isolated from patients with menstrual and nonmenstrual toxic shock syndrome (nine cases) or staphylococcal scarlet fever (three cases). These strains were selected because they produced none of the toxins known to be involved in these syndromes (toxic shock syndrome toxin 1 and enterotoxins A, B, C, and D), enterotoxin E or H, or exfoliative toxin A or B, despite the fact that superantigenic toxins were detected in a CD69-specific flow cytometry assay measuring T-cell activation. Sets of primers specific to the enterotoxin G and I genes (seg and sei, respectively) were designed and used for PCR amplification. All of the strains were positive for seg and sei. Sequence analysis confirmed that the PCR products, corresponded to the target genes. We suggest that staphylococcal enterotoxins G and I may be capable of causing human staphylococcal toxic shock syndrome and staphylococcal scarlet fever.

FIG. 1

Southern blot hybridization of DNAs of S. aureus strains with sei and seg probes. Total DNA was digested with HindIII, separated by agarose gel electrophoresis, transferred to positively charged nylon membranes, and probed with the indicated DIG-labelled probes. Lanes contain DNAs of three S. aureus strains found to be PCR positive for seg and sei (lanes 1, A980483; lanes 2, TC-7; and lanes 3, A900322) and five S. aureus strains found to be PCR negative for seg and sei (lanes 4, FRI-1169; lanes 5, FRI-569; lanes 6, RN-450; lanes 7, A970237; and lanes 8, A990204).