FP140ANALYSIS OF B LYMPHOCYTE SUBPOPULATIONS IN PRE-DIALYSIS END STAGE RENAL DISEASE PATIENTS

Le résumé fourni par la source

INTRODUCTION AND AIMS: End-stage renal disease (ESRD) is linked to increased incidence and severity of microbial infections, impaired response to vaccination and increased risk of virus associated cancers. A reduction in the number and function of lymphoid cells has been described in patients on chronic hemodialysis, although it is still unclear whether these changes are due to uremia or to renal replacement treatment itself. The present study aimed at analysis of B lymphocyte subsets in a cohort of pre-dialysis ESRD patients. METHODS: B cells (CD19+) and their subsets innate B1a (CD19+ CD5+), naive (CD19+ CD27−) , memory (CD19+ CD27+), CD19+ BAFF+ and CD19+ IgM+, as well as the expression of CD45, a regulator of T- and B-cell antigen receptor signalling on lymphocytes were quantified using flow cytometry in the peripheral blood of 21 pre-dialysis patients, and results were compared to age-matched healthy control group. Exclusion criteria were age <18 or>75 years, active autoimmune or chronic inflammatory disease, medical history of malignancy, corticosteroids or immunosuppresive treatment for the last 12 months. Furthermore, CRP, C3, C4, IgG, IgA, and IgM levels were also evaluated. RESULTS: Mean age of the patients (n=21, M/F 12/9) was 62.4± 12.5 years. ESRD patients had reduced lymphocyte count (1579±711μ/L vs. 2276±482μ/L, p=0.005) compared to controls. Likewise, whereas the percentages of B cell subsets were not particularly affected, the absolute number of almost all subsets was significantly smaller in ESRD patients (CD19+: 81.3±60.4μ/L vs. 162.1 ±64.5μ/L, p=0.005, Naive:55.3±50.9μ/L vs. 97.3±46.3μ/L, p=0.043, Memory: 25.8±16.7μ/L vs. 64.8±40.2μ/L, p=0.001, CD19+BAFF+: 67.9±51.1μ/L vs. 136.8±80.1μ/L, p=0.007, CD19+IgM+: 59.1±47.6μ/L vs. 117.1±70.4μ/L, p=0.013 CD45+: 361.8±278μ/L vs. 812.1±361.1μ/L, p=0.002). The only exception were innate B1a cells which were increased in the ESRD group (percentile: 4.7±4% vs. 0,6±1%, p=0.006 count: 4.1±5.5μ/L vs. 1.1±1.5, p=0.027). Furthermore, IgG was elevated in this group (1259±406mg/dL vs. 842±350mg/dL, p=0.026), as well as CRP (7.86±12.96mg/dL vs. 0.28±0.1mg/dL, p=0.02), while there was no statistically significant difference between C3, C4, IgA and IgM between the two groups. CONCLUSIONS: Significant alterations were noticed in innate and adaptive immunity in patients with ESRD on pre-dialysis stage, with a significant reduction of almost all subsets of B cells, and these changes may be implicated in clinical manifestations, such as frequent infections or impaired response to vaccination.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.