Increased CD4(+)CD16(+) and CD4(+)CD56(+) T cell subsets in Behcet's disease

Behcet's disease is a systemic vasculitis of unknown etiology. Various immu ne abnormalities have previously been shown in Behcet's disease. We investi gated T lymphocyte subsets associated with cytotoxic activity and natural k iller (NK) cells by flow cytometry in 37 patients with Behcet's disease, 38 healthy controls, and 17 diseased control patients. Compared to the health y controls, CD4(+)CD16(+) and CD4(+)CD56(+) subsets were found to be higher in the Behcet's disease group as well as in the disease control group (CD4 (+)CD16(+): B = 5 +/- 3, DC = 14 +/- 14, HC = 3 +/- 2, P = 0.001; CD4(+)CD5 6(+): ED = 11 +/- 5, DC = 18 +/- 17, HC = 8 +/- 6, P = 0.01). CD8(+)CD16(+) and CD8(+)CD56(+) T cell subsets were at normal levels in Behcet's disease but found to be elevated in disease controls. Similarly, NK cells (CD16(+) CD56(+)) were high only in the disease control group. Significant increases in CD4(+)CD16(+) and CD4(+)CD56(+) cell subsets in Behcet's patients and d isease controls suggest that T cell activation patterns of these subsets in Behcet's disease are similar to those in other inflammatory disorders.