Differential gene expression of S100 protein family in leukocytes from patients with Kawasaki disease

S100 family proteins are calcium-binding proteins, some of which have been shown to have intracellular and extracellular functions associated with inflammation. The serum concentration of S100A12 has been reported to increase in the acute phase of Kawasaki disease. The purpose of this study was to evaluate leukocyte gene expressions of S100 family proteins in the acute phase of Kawasaki disease. Ten paired blood samples were obtained from ten patients with Kawasaki disease in the acute phase and in the convalescent phase. We examined leukocyte expression levels of 18 S100 genes in the acute phase compared with those in the convalescent phase by using quantitative real-time polymerase chain reaction. Significantly elevated expression of seven S100 genes (S100A6, A8, A9, A11, A12, S100P, and S100Z) was observed in the acute phase. Conclusion:Of the upregulated S100 genes, calgranulin members of S100 genes (S100A8, S100A9, and S100A12) were most highly expressed in the acute phase. Only one S100 gene, the S100A13 gene, exhibited a significantly decreased expression level in the acute phase.