PCSK9 and inflammatory biomarkers in the early post kidney transplantation period

Various biomarkers have been studied in the early post-kidney transplantation (post-KTx) period in order to identify potential therapeutic targets for improving long-term graft survival. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a biomarker that has recently gained interest in cardiovascular disease but its role still remains to be defined post-KTx.

We prospectively evaluated the levels of PCSK9, interleukin (IL)-6, WBC and C-reactive protein in seventy-three hemodialysis patients undergoing KTx, at 3 time-points; pre-transplantation (day 0) and at 1 and 6-months post-KTx. All data were also analyzed according to donor-type (living or deceased) and compared with hemodialysis patients on transplant waiting list.

At Day 0 there was no difference in WBC, CRP, IL-6 and PCSK9 levels between patients scheduled for transplantation and those who remained on hemodialysis. In transplanted patients WBC, CRP and IL-6 levels were significantly reduced early post-KTx [logIL-6 Day 0: 0.68 (0.33, 0.85) vs. 1-month: 0.57 (0.37, 0.75) vs. 6-months: 0.50 (0.32, 0.69) pg/ml, p=0.01], while PCSK9 levels were significantly increased (Day 0: 199.8±63.0 vs. 1-month: 276.2±79.4 vs. 6-months: 245.9±62.5 ng/ml, p<0.001). In contrast, no change of WBC, CRP, IL-6 and PCSK9 levels was observed in hemodialysis patients on follow-up (p=NS for all). Between living-donor and deceased-donor recipients, analysis showed reduced CRP and increased PCSK9 levels in both groups (p<0.05 for all), while IL-6 levels were reduced in living-donor and increased in deceased-donor recipients 1-month post-KTx. PCSK9 levels were not correlated with renal function, delayed graft function, rejection episodes or inflammatory biomarkers.

PCSK9 levels were increased post-KTx independently from renal function and inflammatory biomarkers, in both living and deceased-donor recipients.