Peripheral blood monocytes reveal an activated phenotype in pediatric uveitis.

OBJECTIVE: To characterize peripheral blood monocytes in uveitis associated with juvenile idiopathic arthritis (JIAU).

METHODS: Peripheral blood monocytes from children with JIA (either with (n = 18) or without uveitis (n = 11)), idiopathic anterior uveitis (IAU; n = 12) and healthy controls (n = 11) were analyzed by flow cytometry.

RESULTS: Percentage of CD14 + CD86+ monocytes and CD86 expression on single cell level were significantly higher in all patient groups than in controls, whereas no major differences existed between patient groups. Frequency of CD39+ (p < 0.05 all groups) and CD73+ monocytes (p = 0.03 JIAU vs controls) was elevated in patients. Disease activity did not influence monocyte phenotypes, but in methotrexate-treated JIAU patients numbers of CCR2+ monocytes were reduced and numbers of CD86+ and CD39+ cells increased.

CONCLUSION: Children with arthritis or uveitis display a distinct monocytic phenotype when compared to cells from healthy children. Phenotypic changes seem to be neither arthritis- nor uveitis-dependent, but may be modified by treatment.