CHARACTERIZATION OF THE T-CELL RECEPTOR V-BETA REPERTOIRE IN KAWASAKI-DISEASE

Kawasaki disease (KD) is a paediatric multisystem necrotizing vasculit is constituting the most frequent cause of acquired heart disease in c hildhood. Conflicting data have been reported regarding expanded T-cel l populations using particular T-cell receptor (TCR) beta-chain variab le (BV) gene segments, suggesting either a superantigen- or a conventi onal antigen-mediated immune response in this disease. In order to fur ther investigate the role of T lymphocytes, cells were stained with an extensive panel of 21 different TCRBV specific monoclonal antibobies (MoAbs) covering almost 70% of all T-cells. Flow cytometry was employe d to analyse the expression of the TCRBV repertoire in the CD4(+) and CD8(+) subsets separately, and of activation markers, in freshly isola ted peripheral blood lymphocytes of 25 Kawasaki disease patients durin g the acute and convalescent phases of the disease. No abnormal usage of any TCRBV family was found, neither acutely nor during convalescenc e, compared with a control group of healthy children. However, a signi ficant increase in interleukin-2 receptor (IL-2R)-expressing T lymphoc ytes restricted to the CD4+ subset was observed in KD patients. Our da ta confirm a strong immune activation in KD that might be of importanc e in the pathogenesis of the disease.