Paper

Oxidative Stress and 'Monocyte Reprogramming' after Kidney Transplant: A Longitudinal Study
Massimo de Cal, Sandra Silva, Dinna Cruz, Flavio Basso, Valentina Corradi, Paolo Lentini, Federico Nalesso, Daniela Dissegna, Volker Goepel, Stefano Chiaramonte, Claudio Ronco

Department of Nephrology, Dialysis and Transplant, St. Bortolo Hospital, Vicenza, Italy

Address of Corresponding Author

Blood Purif 2008;26:105-110 (DOI: 10.1159/000110575)

  Key Words

• Oxidant stress
• Monocyte
• Kidney transplant
• Monocyte function
• Inflammation

  Abstract

Uremia has been implicated in increased oxidative stress (OS) and decreased monocyte HLA-DR expression in chronic kidney disease (CKD) patients. Thus, one would expect normalization of these parameters after successful kidney transplant (KTx). Our aim was to describe patterns of OS and HLA-DR expression after KTx and to explore the effect of renal function and different immunosuppression regimens. 30 KTx patients (20 male; 48 ± 11 years) were enrolled and compared with 20 healthy controls. We measured advanced oxidation protein products (AOPP) and the percentage of monocytes expressing HLA-DR (%DR+) before (preKTx) and after KTx (on days 2, 30, 90, 180 and after 1 year). Compared to controls, patients had a higher preKTx AOPP (152.6 vs. 69.3 µmol/l; p < 0.001). AOPP decreased at 48 h after KTx, achieving values similar to controls. Thereafter, it increased again and remained significantly higher compared to controls, returning to preKTx levels at 90 days. Prior to KTx there was a trend for lower %DR+ in KTx patients compared to controls (96 vs. 98%; NS). Following KTx, patients had a lower %DR+ in the 1st month; then it gradually returned to preKTx levels during the 1st year; at no time did it reach a value similar to controls. Cyclosporine (CyA)-treated patients had a significantly higher AOPP (161.5 vs. 99.5 µmol/l; p = 0.03) and a lower %DR+ (91.7 vs. 96.4; p < 0.05) at 30 days than patients on tacrolimus (FK). Patients on mycophenolate mofetil (MMF) showed a low AOPP (106.9 vs. 168.1 µmol/l; p = 0.05) and a high %DR+ (96.7 vs. 88.2%; p = 0.001) than those on everolimus. After 3 months, CyA-treated patients had a non-significant increase in AOPP levels, whereas those on FK showed a decrease (p < 0.05) as did those treated with MMF (p < 0.05). Successful KTx reduced but did not normalize AOPP, suggesting ongoing OS, perhaps due to persistent mild renal dysfunction and the effects of immunosuppression. HLA-DR expression remained low after KTx, which may be a possible contributing factor to infectious complications after transplantation. Immunosuppressive agents appear to have diverse effects on OS and HLA-DR expression.

Copyright © 2008 S. Karger AG, Basel

  Author Contacts

Claudio Ronco
Department of Nephrology, Dialysis and Transplant
St. Bortolo Hospital, Viale Rodolfi
IT-36100 Vicenza (Italy)
Tel. +39 044 475 3650, Fax +39 044 475 3973, E-Mail cronco@goldnet.it

  Article Information

Published online: January 10, 2008
Number of Print Pages : 6
Number of Figures : 2, Number of Tables : 1, Number of References : 34