Lymphocyte activation marker analysis in patients with sight threatening uveitis

Purpose: To investigate the expression of CD69 on CD4 and CD8 lymphocytes of patients with autoimmune uveitis Methods: Peripheral blood from 14 patients with severe autoimmune uveitis and 15 healthy controls was directly cultured in RPMI for 3 days. T lymphocytes were thereafter analysed by flow cytometry for the expression of CD25, CD69 or CD28, CD69 on CD4+ or CD8+ T cells respectively. Results: The expression of CD69 by CD4+ lymphocytes of patients with uveitis was significantly higher than in control subjects (p=0.029). This difference was more pronounced when CD69 expression was analysed on CD4+CD25++ lymphocytes (p=0.016) and lost for CD4+CD25+ T cells. Besides, the number of CD4+CD25++ lymphocytes was increased in the uveitis group (p=0.01). However, we did not observed any correlation between the level of CD69 on CD4+ lymphocytes and the severity or aetiology of the disease. No differences were found when the expression of CD69 was studied on CD8+ lymphocytes. Conclusions: Our results suggest that some patients with autoimmune uveitis have a spontaneous activation of their CD4+CD25 ++ lymphocytes.