P0936INJURY OF NEUTROPHILS DURING HAEMODIALYSIS AND ITS INVOLVEMENT FOR DEVELOPMENT OF CHRONIC MICROINFLAMMATION

Abstract

Abstract Background and Aims Owing to the quality developments of membrane material and dislysis water, it is believed that the biocompatibility of haemodialysis (HD) system has been considerably improved. However, mortality and morbidities of dialysis patients have remained unacceptably high, which raises a question as to the biocompatibility improvement of current HD systems. Method Seventy-one patients on regular HD (male/female: 52/19, mean age: 63 years old, median HD duration: 19 months, HD session 3 times a week for 3 to 4 hours each by using high performance synthetic membrane) at Tohoku University Hospital were examined. Blood samples were obtained from all patients before and after the HD session, to measure followings; number of white blood cell fraction, and apotosis cells, plasma levels of following molecules; myeloperoxidase (MPO), pentraxin 3, angiogenin, lactoferrin, complement (C3a, C5a, C5b-9), and 17 cytokines. Apoptosis (positive for Annexin-V-FITC and negative for propidium iodide) was measured in 100,000 cells by flow cytometer, and plasma molecules were measured by ELISA kit. Results The main findings of this study were as follows (changes in the values after HD as compared to the pre HD); the significant decrease of leukocytes counts (neutrophil and lymphocyte), significant increases of apoptosis positive cells of leukocytes (neutrophiles and monocytes), significant increases of plasma MPO and pentraxin3 levels, significant decrease of angiogenin, and, no or only marginal changes in plasma pro-inflammatory cytokine levels and complement products. There was a significant positive correlation between the change in MPO and apoptosis before and after HD. Conclusion Bio-incompatibility of HD has remained a crucial issue even in the current systems. Among the several pathologies, process of neutrophile apoptosis accompanying MPO degranulation, may plays a central role for developing microinflammation. In this regard, change of plasma MPO could be a clinical marker for the biocompatibility of HD system. And in order to achieve better patients’ outcomes, innovative HD systems which fully improve biocompatibility are needed.