Objective Although the cause of juvenile idiopathic arthritis (JIA), a heterogeneous group of childhood arthritides and systemic lupus erythematosus (SLE) remains unknown, it is well known that cytokines are the main mediators of inflammation. Th1 cytokines, such as IL-1, IL-2, IL-8, IL-12, tumour necrosis factor (TNF)-α, and (IFN)-γ, bear proinflammatory functions, whereas Th2 cytokines such as IL-4, IL-5, and IL-10 support anti-inflammatory tasks. Th1-produced IL-6 acts as both a pro and anti-inflammatory cytokine. This study’s aim is to investigate how immunological profiles differ in JIA subgroups and SLE compared with healthy controls by measuring Th1/Th2 cytokine serum levels.
Methods 150 children (29 systemic JIA, 38 persistent oligoarthritis, 15 seronegative polyarthritis (SNP), 12 enthesitis-associated arthritis (EAA), 24 SLE, 32 healthy controls) were included in this study. A multiplex fluorescent bead immunoassay was used for quantititative detection by flow cytometry of IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IFN-γ, and TNF-α in whole blood.
Results Leading proinflammatory cytokines in systemic JIA and oligoarthritis are IL-12 and IL-6, their anti-inflammatory antagonist is IL-4. Outstanding cytokines in SNP are proinflammatory TNF-α and IL-1β with their opponent IL-5. EAA is associated with the pro-/anti-inflammatory match IL-1β and IL-2/IL-10, whereas SLE is associated with INF-γ/IL-4. IL-8 was not significantly increased in the diseases.
Conclusions In this study we demonstrated different cytokine profiles with leading pro and anti-inflammatory cytokines in different autoinflammatory diseases. Some profiles might be useful for determinating the JIA subtype. Furthermore, the leading proinflammatory cytokines may be targets for new therapy strategies in future.