Phagocyte dysfunction in polymyalgia rheumatica and other age-related, chronic, inflammatory conditions

Abstract

This study was conducted to evaluate phagocyte function in patients with age-related chronic inflammatory conditions. It included 95 patients with PMR, 17 with GCA, 40 with EORA, and 25 age-matched HCs. Serum IL-8 was determined with a bead array. The chemotactic capacity, phagocytic ability, and oxidative burst activity of circulating leukocytes were determined with flow cytometry kits. Patients with active chronic inflammatory diseases showed a significant increase in circulating levels of IL-8 that remained elevated in patients with PMR or EORA, despite treatment. No correlation was found between circulating IL-8 and the migratoty capacity of neutrophils. Neutrophils from patients with active EORA without stimulus and after fMLP stimuli showed a higher capacity to migrate than those of the HCs (P=0.033). The phagocytic activity of granulocytes in the patients with GCA was significantly higher than in the HCs and the patients with PMR or EORA (P<0.05). The percentage and MFI of phagocytes that produce ROIs when stimulated with Escherichia coli was significantly reduced in neutrophils and monocytes from the patients with age-restricted inflammatory conditions. We concluded that the effector functions of phagocytes, determined to be chemotaxis, phagocytosis, and oxidative burst, are deregulated in age-restricted inflammatory disorders and may have a pathogenic role.