Phenotype of Innate Immune Cells in Uveitis Associated with Axial Spondyloarthritis- and Juvenile Idiopathic Arthritis-associated Uveitis

Purpose: To analyze circulating immune cells in patients with anterior uveitis (AU) associated to axial spondyloarthritis (SpA), or juvenile idiopathic arthritis (JIA). Methods: Venous blood samples were collected from healthy controls (n = 16), and either SpA (n = 19) or JIA (n = 23) patients with associated anterior uveitis (AU) during active flare, or after >= 3 months of inactivity. Frequencies of CD56(+), MHC-I+, and S100A9(+) monocytes, CCR7(+) dendritic cells, CD56(+dim) natural killer (NK) cells and CD3(+)CD56(bright) T-cells were analyzed via flow cytometry. Serum S100A8/A9 levels were determined via ELISA. Results: SpA patients showed a reduced frequency of CD56(+dim) NK cells during uveitis activity, a constitutively activated monocyte phenotype, and elevated S100A8/A9 serum levels. In contrast, JIAU patients showed elevated frequencies of CD56(+) monocytes and CCR7(+) DC. Conclusion: Phenotype of peripheral immune cells differ between patients, probably contributing to different courses of acute onset AU in SpA and insidious onset AU in JIAU patients