Canges of Peripheral IFN-r-Producing CD4(+) and CD4(-) Cell Frequencies in Kawasaki Disease

ABSTRACT

PURPOSE: This study was performed to analyze the frequencies of peripheral IFN- gamma -producing cells at the single cell level, and to determine concentrations of circulating interferon- gamma (IFN- gamma) in the acute and subacute phases of Kawasaki disease(KD). METHODS: Ten patients with KD were studied and seven healthy children were selected as control subjects. Using immunofluorescent detection of intracellular IFN-gamma in CD4(+) and CD4(-) the cells, the frequencies of IFN-gamma -producing cells in peripheral blood mononuclear cells(PBMC) were studied. Circulating IFN-gamma levels were measured by enzyme-linked immunosorbent assay. RESULTS: The frequencies of peripheral blood CD4(+) and CD4(-) IFN- gamma -producing cells in acute phase KD patients were significantly lower than in subacute phase KD patients and control children(P<0.05). CD4(-) cells, thought to be mainly composed of CD8(+) cells, appeared to be more responsible for the reduced frequencies of total IFN- gamma -producing cells than CD4(+) cells. There were, however, no differences in frequencies of IFN- gamma -producing cells between KD patients in the subacute phase and control group children. In contrast, serum IFN- gamma levels were higher in KD patients in the acute phase than in the subacute phase(P<0.05). Conclusion The above results show an increased level of circulating interferon-gamma and a decreased emergence of peripheral IFN-gamma-producing cells in acute KD patients, suggesting transient infiltration of activated IFN-gamma-producing cells into the inflammatory sites during acute KD. These findings also support the hypothesis that IFN-gamma plays an irnportant role in the pathogenesis of KD-related vasculitis.