[Immunological investigations on pathogenesis of staphylococcal scalded skin syndrome].

Staphylococcal exfoliative toxin (ET) is an extracellular product of Staphylococcus aureus isolated from patients with staphylococcal scalded skin syndrome (SSSS) which includes Ritter's disease, bullous impetigo and staphylococcal scarlet fever, and has been regarded as the causative agent of SSSS. The ET has not only a splitting effect at the granular layer of skin in human and mice but also an immunogenicity to human and mice. Using experimental animals and clinical specimens of patients with or without SSSS, the immunological investigation were performed and following results were obtained. 1) When some inbred and congenic resistant strains of mice were immunized with serotype A ET (ETA), they were divided into the high anti-ETA antibody producers (high responders) and the low responders. The gene controlling antibody response to ETA in mice is located in the I-A subregion in the major histocompatible complex (H-2 complex), and its function seems to be at least related to antigen recognition at the T-lymphocyte level. 2) Neonatal mice are generally susceptible to ETA regardless of their H-2 haplo-type. However, the neonatal mice born to a high-responder mother immunized with ETA were resistant to the subcutaneous challenge of ETA, but those born to an immunized low-responder mother were susceptible to the challenge. 3) The relationship between susceptibility and immune response to ETA in some mammalians could be divided into three groups: the possession of resistant skin and high production of antibody to ETA (rabbits and rats); the possession of resistant skin and low production of antibody to ETA (golden hamsters and guinea pigs); the possession of sensitive skin and various titers of antibody to ETA (humans and mice). 4) The incidence of ET producing strains of Staphylococcus aureus in various clinical specimens obtained from patients without SSSS was 12% (50 out of 418 strains) in our epidemiological investigation. The percentages of antibody to ETA in sera obtained from healthy males and females were 23% and 29%, respectively. Eventually, ET-producing strains of Staphylococcus aureus seem to be spread out wider than the microbiological result obtained from clinical specimens. 5) The mitogenic responses of lymphocytes isolated from patients with the first impetigo could be measured by using PHA, and the five-of them were in the low range, whereas lymphocytes from patients with recurrent impetigo were in the normal range on this survey. Maybe this results suggest the T lymphocyte functions of some patients with impetigo are deteriorated.(ABSTRACT TRUNCATED AT 400 WORDS)