ESPN 50th Annual Meeting

ESPN 2017


 
Complement activation in relation to donor specific antibodies after kidney transplantation
Andreas Heilos 1 Blanka Mezö 2 Farsad Eskandary 1 Gregor Bond 1 Georg Böhmig 1 Dorottya Csuka 1 Zoltán Prohászka 2 Krisztina Heindl-Rusai 1

1- Medical University of Vienna
2- Semmelweis University
 
Introduction:

Antibody mediated rejection (AMR) is the major immunological cause of kidney transplant failure also in the paediatric population. According to current knowledge, late AMR is classically caused by the development of donor specific antibodies (DSA) and the complement system plays a critical role in its pathomechanism. The aim of this work was to determine the levels of various complement activation products in kidney transplant recipients.

Material and methods:

106 adult kidney transplanted patients who had detectable DSA after transplantation (DSA+, 189 days to 29 years post-transplantation) were involved in the study. 106 DSA-negative patients were matched as controls using 1:1 propensity score matching. Two patients were excluded due to poor sample quality. The levels of complement activation products (C3a, SC5b-9, C4d and Bb) were measured by enzyme-linked immunosorbent assay (ELISA) using EDTA plasma samples.

Results:

Activation product levels were compared between the DSA-positive and negative groups. Mean C3a concentration in the plasma of DSA+ patients was 97.3 ng/ml (SD 38.9), compared with 93.86 ng/ml (SD 41.38) in the DSA- group (P>0.05). Mean SC5b-9 concentration in the DSA+ patients was 223.3 ng/ml (SD 86.8), compared with 222.8 ng/ml (SD 83.5) in the DSA- group (P > 0.05). Mean level of C4d in the DSA+/- groups was 2.7 µg/ml (SD 1.19) compared with 2.93 µg/ml (SD 1.65) (P> 0.05). Mean Bb levels of the DSA+/- patients found to be 1.3/1.15 µg/ml (SD 0.66/0.38) (P > 0.05). 

Conclusions:

Levels of complement activation products in kidney transplant recipients were determined. No significant difference in plasma levels of activation markers for C3 (C3a), terminal pathway (SC5b-9), classical pathway (C4d) and alternative pathway (Bb), was observed in DSA positive and negative patients. Further analysis is necessary to identify association of complement activation with the histological signs of AMR.