抄録
Background: The similarities between Kawasaki disease (KD) and superantigen (SA) diseases indicate that a microbial SA
might cause KD. Viral diseases can trigger an endogenous SA.
Methods: We evaluated expression of Vß2 (responding to staphylococcal TSST-1) and Vß7 (responding to the endogenous SA
induced by type-1 interferon or Epstein-Barr virus infection) on T cells from 70 KD patients along with the following control subjects:
18 non-vasculitic patients (NVs), 7 patients with anaphylactoid purpura (AP), and two with neonatal TSS-like exanthematous
disease (NTED), a typical SA disease. We examined the correlation of clinical features of KD with Vß2+ or Vß7+CD4+T cell
populations.
Results: The Vß2+CD4+T cell rates were comparable between KD patients (9.9±2.9%) and NVs (9.0±1.8%), but were lower in
AP patients (6.6±1.8%). However, the Vß2+CD4+T cell rate was significantly higher in KD patients with erythematic BCG inoculation
site lesions (10.8±3.2%) than in those without (8.8±2.1%) and NVs (9.0±1.8%), but much lower than in NTED patients (25.2%,
16.9%). Multivariate linear regression analysis with elevation of Vß2 expression as a dependent variable revealed significant correlations
with BCG. In contrast, Vß7+CD4+T cell rates were not significantly different between KD patients and other study subjects.
Conclusion: While we were unable to find evidence supporting the involvement of the endogenous SA in the pathogenesis of
KD in this study, modest expansion of the Vß2+CD4+T cell population in a subgroup of KD with erythematic BCG inoculation site
lesions implies the involvement of a microbial agent(s) different from TSST-1 as well as immunopathological heterogeneity of KD.
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