Interleukin 1, interleukin 6, interleukin 10, and tumor necrosis factor α in active and quiescent systemic lupus erythematosus.

OBJECTIVES

Several studies have investigated the cytokine profile of patients with systemic lupus erythematosus (SLE); however, their role is still controversial, mostly because SLE has a heterogeneous disease manifestation. We measured 4 of the most important cytokines in patients with SLE after dividing them in uniform groups according to disease activity and organ involvement.

MATERIALS AND METHODS

Eighty-two adult female patients with SLE were divided into 3 groups according to disease activity and organ involvement: Group A (SLE activity index [SLEDAI] score, 7 ± 0.4) included subjects with newly diagnosed, active SLE, investigated before starting therapy. Group B (SLEDAI score, < 6) included patients without renal involvement, treated with prednisone and azathioprine or hydroxychloroquine. Group C (SLEDAI score, < 6) included patients with lupus nephritis, treated with methylprednisolone and cyclophosphamide, reaching complete remission. Fourteen healthy females served as controls.

RESULTS

Interleukin-1 levels were 1.0, 0.8, 0.7, and 0.25 pg/mL in groups A, B, C, and D, respectively. Interleukin-6 levels were 3.2, 3.6, 4.0, and 1.4 pg/mL in groups A, B, C, and D, respectively; Il-10 levels, 3.05, 1.1, 1.5, and 1.65; tumor necrosis factor-α levels, 8.75, 5.8, 5.4, and 3.6. Interleukin 1, IL-6, and tumor necrosis factor-α were significantly higher in the patients with SLE than in the healthy controls; IL-1 was significantly higher in group A than in group C. Interleukin 10 showed positive correlation with C-reactive protein, whereas it showed negative correlation with C3.

CONCLUSIONS

Data from our cohort, one of the largest so far reported, add to the evidence that proinflammatory cytokines such as Interleukin-1, Interleukin-6, Interleukin-10 and tumor necrosis factor-α are important in SLE pathogenesis.