Enhanced gene expression of chemokines and their corresponding receptors in mononuclear blood cells in chronic heart failure—modulatory effect of intravenous immunoglobulin

OBJECTIVES We sought to study the gene expression of chemokines and their corresponding receptors in mononuclear blood cells (MNCs) from patients with chronic heart failure (CHF), both of which were cross-sectional and longitudinal studies during therapy with intravenous immunoglobulin (IVIg). BACKGROUND We have recently demonstrated that IVIg improves left ventricular ejection fraction (LVEF) in patients with CHF. Based on the potential pathogenic role of chemokines in CHF, we hypothesized that the beneficial effect of IVIg may be related to a modulatory effect on the expression of chemokines and their receptors in MNCs. METHODS We examined: 1) the gene expression of C, CC and CXC chemokines and their receptors in MNCs from 20 patients with CHF and 10 healthy blood donors; and 2) the expression of these genes in MNCs from 20 patients with CHF randomized in a double-blind fashion to therapy with IVIg or placebo for 26 weeks. RESULTS Our main findings in CHF were: 1) markedly raised gene expression of macrophage inflammatory protein (MIP)-1α, MIP-1β and interleukin (IL)-8; 2) enhanced gene expression of their corresponding receptors; 3) modulation in a normal direction of this abnormal chemokine and chemokine receptor gene expression during IVIg, but not during placebo therapy; 4) down-regulation of MIP-1α, MIP-1β and IL-8 during IVIg at the protein level in plasma; and 5) a correlation between down-regulation of MIP-1α gene expression and improved LVEF during IVIg therapy. CONCLUSIONS Our results further support a pathogenic role for chemokines in CHF and suggest that IVIg may represent a novel therapeutic approach, with the potential to improve LVEF in patients with CHF, possibly by modulatory effects on the chemokine network.