Altered cytokine expression by macrophages from HLA-B27-positive spondyloarthritis patients without evidence of endoplasmic reticulum stress

Abstract

Objectives. We investigated endoplasmic reticulum (ER) stress and cytokine expression in peripheral blood-derived macrophages and synovial tissue from HLA-B27 + SpA patients. Methods. Macrophages from healthy donors, SpA and RA patients were polarized with IFN-c or IL- 10 and activated with lipopolysaccharide. Expression of ER stress markers (BiP, CHOP, ERdj4) and cytokines (IL-23, IL-12, TNF, IL-10) was measured by qRT-PCR. Expression of ER stress markers and cytokines in synovial tissue from SpA patients was evaluated by microarray analysis. Results. Macrophages from HLA-B27 + SpA patients did not show elevated ER stress markers. However, the expression of IL-23 and IL-12 by peripheral blood-derived macrophages was higher in HLA-B27 + SpA in comparison with healthy donors. Synovial tissue from HLA-B27 + SpA patients showed higher expression of TNF compared with HLA-B27 + SpA patients. Conclusion. HLA-B27 + SpA patients showed increased expression of IL-23, IL-12 and TNF without evidence of ER stress.