CD56+ T cells in the peripheral blood of uveitis patients.

AIMS Natural killer T (NKT) cells, T lymphocytes expressing both T cell and NK cell markers, are suggested to be involved in autoimmune diseases. To examine the relation between the pathogenesis of uveitis and CD56+ T cells, which are thought to be a type of human NKT cells, we investigated peripheral CD56+ T cells in uveitis patients. METHODS 41 uveitis patients (Behçet's disease (BD), 14; sarcoidosis (SAR), eight; Vogt-Koyanagi-Harada disease (VKH), five; idiopathic uveitis (IU), nine; and others, five) and 19 healthy controls participated in this study. Cell surface antigens of lymphocytes were analysed by use of monoclonal antibodies and flow cytometry. RESULTS The proportion of CD56+ T cells in patients with BD was higher than in controls and in patients with SAR, VKH, IU, and others. CONCLUSION Increased peripheral CD56+ T cells might be relevant to the pathogenesis of uveitis in BD, and increase of peripheral CD56+ T cells may be one of the laboratory findings to suggest that uveitis originates from BD.