Serum Cytokine Profile in Asian Indian Patients with Takayasu Arteritis and its Association with Disease Activity.

Background: Arterial inflammation Takayasu arteritis (TA) is an outcome of balance between pro- and anti-inflammatory cytokines. Comprehensive assessment of these cytokines is important for understanding pathogenesis and assessing disease activity.

Objective: To study pro- and anti-inflammatory cytokines representing different T-helper cell pathway in serum samples of Asian Indian patients with TA and to assess their association with disease activity.

Methods: Consecutive Indian patients with TA were assayed for serum interferon-γ, interleukin-6, interleukin-23, interleukin-17, interleukin-10 and transforming growth factor- β levels at baseline and follow up visit. Patients were grouped into active and stable disease based on Indian Takyasu Arteritis clinical Activity Score-2010. Serum levels of these cytokines between active and stable disease and between baseline and follow up visits were compared by non-parametric tests.

Results: Among 32 patients enrolled, 15 were classified as active while 17 as stable disease at baseline. IFN-γ levels were significantly higher in active disease than stable disease (p=0.0129) while other cytokines did not differ significantly between 2 groups. Serum levels of none of the cytokines changed significantly over 2 visits in both responders and non-responders. IL23 levels positively correlate with disease duration ((r=0.999; p<0.005). Modest correlation was observed between IFN-γ and IL23 levels at both baseline and follow up and between IFN-γ and IL-6 and CRP at follow up.

Conclusion: IFN-γ levels are raised in active disease in TA and correlates well with other biomarkers of disease activity and proinflammatory cytokines. There is also a direct correlation between Il-23 levels and disease duration.