The role of T cells in Kawasaki disease.

Kawasaki disease (KD) is the most common pediatric vasculitis and the most frequent cause of acquired heart disease in children in the U.S. Its etiopathogenesis is unknown, although T cell, B cell and monocyte/macrophage populations have all been implicated in the disease. The precise role played by T cells is unclear. Analysis of T-cell activation markers in peripheral blood has demonstrated conflicting data. Study of tissue samples, which could clarify this issue, has been limited. Expansion of T cells bearing V beta 2 and V beta 8 has been reported during the acute phase of the disease, suggesting that exposure to a superantigen may represent one of the etiologies. Other studies, however, have not confirmed V beta expansions of T cells; in fact, indirect evidence that a conventional antigen may be involved has been reported in certain patients. Together, these various studies suggest that the clinical entity of KD may be induced by a variety of etiologic agents.