Serum levels of IgG4 and soluble interleukin-2 receptor in patients with coronary artery disease

Background: Immunoglobulin G4 (IgG4)-related immuno-inflammation has been suggested to play a role in the development of remodeling of arterial wall. We investigated the association between serum concentrations of IgG4 or soluble interleukin-2 receptor (sIL-2R) and coronary artery disease (CAD). Methods: Serum concentrations of IgG4 and sIL-2R were measured in 286 patients who underwent coronary angiography. Results: In patients with CAD, the medians of serum concentrations of IgG4 (393 mg/dl) and sIL-2R (388 U/ml) were significantly higher than corresponding values in patients without CAD (IgG4 27.0 mg/dl, sIL-2R 312 U/ml). In receiver-operating characteristic curve analysis, the area under the curve of sIL-2R and IgG4 for the presence of CAD was 0.634 and 0.632, respectively. Age- and gender-adjusted logistic regression analysis showed that both of the fourth quartile of sIL-2R concentrations (>= 509 U/ml) and that of IgG4 concentrations (>= 57.7 mg/dl) were found to be associated with CAD with an odds ratio of 2.82 and 4.08, respectively, compared with the corresponding lowest quartile. Conclusions: Serum concentrations of IgG4 and sIL-2R were increased in patients with angiographically-proven CAD, suggesting that IgG4-related immuno-inflammation may also have a role in the development and/or progression of coronary artery atherosclerosis. (C) 2011 Elsevier B.V. All rights reserved.