Objectives: Single nucleotide polymorphisms of CD11a and CD11c have been suggested as susceptibility loci in Korean patients with Behçet's disease (BD). As immunoregulatory roles of CD11c+CD8+T cells were previously observed in multiple autoimmune and autoinflammatory diseases, we aimed to investigate CD11a and CD11c in CD4+ and CD8+ subpopulation of BD patients.
Methods: Peripheral-blood mononuclear cells were isolated from 21 patients with active BD, 26 patients with inactive BD, 20 patients with recurrent aphthous ulcers (RAU), and 23 healthy controls (HCs). The surface expression of CD11a and CD11c in CD4+ and CD8+ cell populations was analyzed by flow cytometry, and CD11a and CD11c mRNA and protein levels from puri ed CD8(+) T cells were analyzed using real-time polymerase chain reaction and western blot.
Results: The frequencies of CD11a+ and CD11c+ cells were significantly increased in the CD4+ and CD8+ cell populations of active-BD patients, respectively, than that in the HCs. Additionally, both CD11a and CD11c mRNA and protein levels were significantly elevated in the CD8+ T cells of active-BD patients than that in the HCs.
Conclusions: The CD8+ T cells of BD patients exhibited increased CD11c expression levels. Upregulation of CD11c in CD8+ cells may contribute to BD pathogenesis.