The activation of complement system in different types of renal replacement therapy.

Abstract

The complement cascade is a part of innate immune system that responds rapidly to defend the host against invading microorganisms and complete the action of immune cells. The activation of the complement system leads to increased inflammatory response, fibrosis of tubulointestinal tissue and progression of chronic kidney disease (CKD). The purpose of this study was to determine whether the type of renal replacement therapy has an effect on activation of the complement system. The study included 79 patients with CKD stages 4 - 5 according to Kidney Disease Improving Global Outcomes (KDIGO) guidelines on conservative treatment (CKD4-5) (n = 28), on peritoneal dialysis (PD) (n = 21) and undergoing chronic haemodialysis (HD) (n = 30). The concentrations of complement components C3a, C5a and C5b-9 were determined in plasma using the ELISA method. The highest concentration of C3a was found in PD group and differed significantly from HD group, both before and after haemodialysis treatment and CKD4-5 patients (P = 0.00001). The C5a concentration in HD patients was significantly higher than in PD patients and CKD4-5 group (P = 0.0001). The C5a and C5b-9 concentrations significantly increased during the haemodialysis session (P = 0.027 and P = 0.01, respectively). The values of C5b-9 observed in PD and CKD4-5 groups were significantly lower, than in HD patients (P = 0.0005). In HD patients the negative correlations were found between the time of haemodialysis treatment and C5b-9 concentration, both before and after haemodialysis session (Rs = -0.436, P = 0.016 and Rs = -0.365, P = 0.046, respectively). The type of renal replacement therapy influences the complement activation, which is the most intense during the haemodialysis treatment and correlates negatively with the haemodialysis vintage. The promising therapeutic intervention may be an improvement of HD biocompatibility.