Upregulated interleukins (IL-6, IL-10, and IL-13) in immunoglobulin G4-related aortic aneurysm patients

Interleukin (IL) 10 and IL-13 upregulation in the aortic adventitia reflected T-helper-2 and regulatory T immune reactions in immunoglobulin (Ig) G4-related aortic aneurysms (IgG4-AAs) similar to other IgG4-related diseases. Furthermore, IgG4-AA was characterized by IL-6 upregulation. In IgG4-AA, serum IL-6 correlated with serum IgG4 and adventitial thickness. Multiple cell populations, including the endothelium, mesenchymal cells, and macrophages in the adventitia, additionally contributed to the hyper-IL-6 syndrome in IgG4-AA. Local IL-6 synthesis in IgG4-AA adventitia may play a role in disease pathogenesis and progression. Serum IL-6 would be a useful biomarker for disease activity, and an IL-6 inhibitor may serve as a new effective therapy for IgG4-AA.