Soluble CD163 serum levels are elevated and correlated with IL-12 and CXCL10 in patients with long-standing rheumatoid arthritis

Abstract

CD163, a membrane glycoprotein restricted to monocyte-macrophage cell lineage, is released in the terminal phase of acute inflammation and during chronic inflammation, with anti-inflammatory and antiangiogenic role. The proteolytically detached ectodomain of CD163 is the soluble component sCD163. A few studies were performed regarding circulating sCD163 in human diseases. Only two were accomplished in patients with rheumatoid arthritis (RA). Our concern was (1) to evaluate sCD163 serum concentrations in active RA patients with long-standing evolution, (2) to correlate them with clinical parameters, laboratory markers, disease activity, and (3) to search possible relationships with some cytokines (IL-12, IL-17) and chemokine (CXCL10), involved in RA pathogenesis. First and third topics were not achieved until now, and the second one points out discordant findings and unspecified aspects. It was achieved immunoassay of serum sCD163, IL-12, IL-17, CXCL10 and traditional methods for RA laboratory markers. The mean sCD163 level of 33 patients was significantly higher than in 20 normal controls (p = 0.0001), 59.3 % of them with concentrations above normal cut-off value. sCD163 levels were weakly correlated with CRP and RF but not with ERS and disease activity. IL-12 and CXCL10 serum levels strongly correlated with sCD163 concentrations, while IL-17 positively but insignificantly correlated. In conclusion, serum sCD163 levels are significantly elevated in long-standing RA patients, but sCD163 has no role as a biomarker of disease activity. High correlation of sCD163 with IL-12 and CXCL10 suggests the association of their well-known anti-inflammatory function in long-standing RA patients.

Elevated Plasma Soluble CD14 and Skewed CD16+ Monocyte Distribution Persist despite Normalisation of Soluble CD163 and CXCL10 by Effective HIV Therapy: A Changing Paradigm for Routine HIV Laboratory Monitoring?

“…In the case of CXCL10 this is in keeping with previous studies [18] , [19] , as well as observations in acute HIV-1 infection that plasma CXCL10 levels provide a very early predictive measure of set-point viral load, CD4 T cell activation and disease progression [27] most likely through direct stimulation of monocyte and plasmacytoid dendritic cell CXCL10 production via toll-like receptor ligation [18] . Similar evidence has been provided for a correlation between plasma HIV RNA levels and sCD163 [17] , and the interrelationship between sCD163 and CXCL10 identified in this study has also been noted in rheumatoid arthritis [28] – suggesting common activation pathways for these molecules.…”

Antibiotics modulate intestinal immunity and prevent necrotizing enterocolitis in preterm neonatal piglets

“…Complexes of S100A8/S100A9 (calprotectin) are also ligands of Toll-like receptor 4 (21) and contribute to ongoing innate immune activation in inflammatory disease states. CD163 is produced by activated macrophages and elevated in inflammatory diseases (20,28), whereas both IL8 and CXCL6 are potent neutrophil chemoattractants. The reduced levels of MPO in the ANTI pigs are consistent with the reduction in these inflammatory chemokines.…”

Clinical significance of sCD163 and its possible role in asthma

“…The expression of CD163 is induced by corticosteroids (3,33–35), IL-10 (3,22,33–35), IL-6 (12,34,36), IL-12 (37), the chemokine (C-X-C motif) ligand (CXCL) −10 (37), and oxidative stress (8). sCD163 protects monocytes from hyperactivation during bacterial infections by dampening the secretion of the proinflammatory cytokines TNF-α, IL-1β, IL-6 and IL-8 (38).…”

“…Therefore it may be hypothesized that sCD163 is implicated in RA activity, although an association between sCD163 and disease activity has yet to be demonstrated (37,76). sCD163 shed from resident tissue macrophages were abundant in inflamed synovium (77).…”