Platelet and Monocyte Activity Markers and Mortality in Patients with End-Stage Renal Disease
CLINICAL LABORATORY
Authors: Gergei, Ingrid; Kaelsch, Thorsten; Maerz, Winfried; Kraemer, Bernhard K.; Kaelsch, Anna-Isabelle
Abstract
Background: The association of platelet and monocyte activity markers with long-term mortality was assessed in hemodialysis (HD) patients. Methods: In 41 HD patients (25 male, 16 female), surface expression of CD40L and CD62P on platelets, tissue factor (TF) binding on monocytes, and platelet-monocyte aggregates were measured by flow cytometry. Plasma levels of MCP-1, IL-6, TNF alpha, and soluble CD40L were analyzed by enzyme linked immunosorbent assay. Cox proportional hazard regression analyses and Kaplan-Meier curve were calculated. The predefined endpoint was all-cause mortality. Results: The study follow-up was 11.54 years. Thirty-one patients (75.6%) died within the study period. Mean patient survival after study inclusion was 5.45 +/- 4.24 years. TF on monocytes above the median of the study population was significantly and independently associated with total mortality (HR (95% CI) 3.45 (1.32 - 9.07); p = 0.01). Cumulative mortality in patients with TF on monocytes above median was significantly higher compared to patients with TF on monocytes below median value (log rank p < 0.01). Platelet-monocyte aggregates, the expression of CD40L and CD62P on platelets, and plasma levels of sCD40L, IL-6, MCP-1, and TNFu were not significantly correlated with mortality. Conclusions: The present study confirms a high mortality in ESRD patients. TF binding on monocytes was significantly correlated with increased mortality and may identify a subgroup of patients at higher risk.
IgG4-related disease: How to place it in the spectrum of immune-mediated and rheumatologic disorders?
MODERN RHEUMATOLOGY
Authors: Borges, Tiago; Silva, Sergio
Abstract
IgG4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory disorder that results from massive expansion of polyclonal IgG4-switched B and/or plasma cells. It can virtually affect all organs and its diagnosis relies on clinical, serological and histopathological criteria. The role of autoimmunity and adaptive immune system in IgG4-RD is reflected in plasmablast differentiation, germinal center formation and IgG4 production induced by CD4+ cells expressing CD40 ligand. IgG4-RD has been considered to be a Th2/Treg-driven disorder, but follicular helper T cells are important in driving the IgG subclass switch. Prompt clinical responses to rituximab, human leukocyte antigen (HLA) associations and the presence of autoantibodies also point to the importance of adaptive immune system. However, innate immunity may induce storiform fibrosis through T-cell independent responses as a consequence of toll-like receptors activation by microbe-and damage-associated molecular patterns, while macrophages and basophils also appear to have a significant role in IgG4-RD pathogenesis. Allergic mechanisms may drive IgG4-RD, but only a subgroup has elevated IgE serum levels and peripheral eosinophilia. Finally, the 2012 revised Chapel Hill Consensus Conference nomenclature pointed IgG4-RD as a cause of large-vessel vasculitis. This review aims to discuss how to place IgG4-RD in the spectrum of immune-mediated and rheumatologic disorders.