Immunological Profile of Patients with Rheumatoid Arthritis and Asthma

Introduction: The aim of this study was to investigate cytokine profiles in patients with both rheumatoid arthritis (RA) and bronchial asthma (BA).

We studied 25 patients with RA, 25 with BA, and 25 with both RA and BA (BARA). A respiratory questionnaire was completed by all the patients, they underwent spirometry, and their production patterns of selected T helper (Th)1, Th2, and Th17 cytokines were assessed.

BA patients had spirometry findings similar to BARA patients, while RA patients had normal spirometry. BA patients produced significantly higher levels of interleukin (IL)-5 (p = 0.03) and IL-10 (p = 0.03) than patients with RA. Median levels of IL-17A and IL-17F and interferon (IFN)-γ were higher (p = 0.001, 0.004, and 0.04) in RA patients than in BA patients. No differences were seen in the levels of cytokines produced by BA patients compared to BARA patients. IL-4 and IL-10 levels were higher (p = 0.04 and 0.03) in BARA patients than in RA patients, while levels of IL-17A and IFN-γ were higher (p = 0.037 and 0.009, respectively) in RA patients than in BARA patients. Ratios of Th1/Th2 and Th17/Th2 cytokines in most combinations were different between RA and BA, and between RA and BARA, but were similar in BA and BARA.

Patients with both BA and RA have a Th2-dominant cytokine profile unlike patients with RA alone. These observations contribute to a better understanding of the immunopathogenesis of these diseases and to the management of patients using cytokine-based therapies.