MO013SENESCENCE-LIKE CHANGES IN B CELL PHENOTYPE IN HEMODIALYSIS PATIENTS

Abstract

\n \n \n End Stage Renal Disease (ESRD) is characterized by susceptibility to infections, high prevalence of cancer and cardiovascular disease and poor response to vaccination. All of the above are potential consequences to compromised immune function seen in ESRD and demonstrated by profound immune cells phenotype changes, resembling the natural course of senescence; therefore termed immunosenescence. Whereas alterations of T cells in ESRD have been largely studied, there are insufficient data regarding B cell immunity. In this study we evaluate the effects of hemodialysis (HD) on B cells, in terms of untimely expression of immunosenescent phenotype.\n \n \n \n B cells phenotype was analyzed by flow cytometry in 25 ESRD patients on HD (M/F 15/10, Mean Age 59±14.7yrs). Patients on HD with systemic diseases, malignancy or recent (<3 months) episode of infection were excluded. Subpopulations, including naïve (IgD+CD27-), IgM memory (IgD+CD27+), switched memory (IgD-CD27+) and late memory (IgD-CD27-) B cells were determined. Findings were compared to 12 healthy controls of similar age.\n \n \n \n In HD patients a severe B lymphopenia was observed; a decrease in B cells both percentage (6.5±2.7% vs 11.9±4.5%, p<0.0001) and absolute number [88(53) vs 229(271) cells/μl, p<0.0001]. Naïve and late memory B cells proportions were similar between patients and controls, however, absolute number was significantly lower in HD patients for both subsets [55(54)vs118(216) cells/μl, p=0.006, and 7(7) vs 21(24) cells/μl, respectively, p=0.001]. Switched memory B cells declined in HD both in terms of percentage [15.7(11.7)% vs 25.7(18.9)%, p:0.03] and absolute number [13(10) vs 59(64) cells/μl, p=0.00].\n \n \n \n Chronic hemodialysis results in B cell phenotype alterations similar to normal aging. Switched memory B cells, the predictors of optimal antibody responses are significantly reduced, and this may act as an additional factor to relative immune deficiency of dialysis patients.\n