Aortic Stiffness in Patients Undergoing Hemodialysis is Positively Related to Antigen Presenting Cell-Dependent T-Lymphocyte Reactivity

Abstract

Background. Aortic stiffness is increased in patients undergoing hemodialysis (HD), and it is associated with an increased cardiovascular mortality. Among others, aortic stiffness has been correlated with serum markers of inflammation, indicating a role of the immune system in its pathogenesis. The aim of this study was to evaluate the impact of antigen-presenting cell-dependent T-lymphocyte reactivity on aortic stiffness in HD patients.Patients and methods. Twenty patients were enrolled in the study. Exclusion criteria were medications or conditions, other than HD, that are known to influence the immune response or aortic stiffness. Antigen-presenting cell-dependent T-lymphocyte reactivity was assessed by cell proliferation of peripheral blood mononuclear cells cultured with or without stimulation with Staphylococcal enterotoxin B (SEB). Cell proliferation was estimated by immunoenzymatic measurement of bromodeoxyuridine uptake. Aortic stiffness was assessed by carotid-femoral pulse wave velocity (PWV) measurement.Results. Linear regression analysis revealed a strong positive relation between carotid-femoral PWV and antigen-presenting cell-dependent T-lymphocyte reactivity, when SEB at concentrations of 1 ng/mL or 10 ng/mL was used as stimulant.Conclusion. The present study confirms that aortic stiffness in HD patients is positively related to antigen-presenting cell-dependent T-lymphocyte reactivity. The greater the ability of the immune system to react to a monocyte-dependent stimulant and, consequently, to provoke an inflammatory response, the greater the stiffness of the aorta. This is in agreement with the observation that aortic stiffness in HD patients is positively related to various serum inflammation markers.