Kidney allografts transplanted simultaneously with liver allografts from the same donor are known to be immunologically privileged. This is especially evident in recipients with high levels of donor-specific anti-HLA antibodies. Here we investigated the mechanisms of liver's protective impact using gene expression in the kidney allograft. Select solitary kidney transplant or simultaneous liver-kidney transplant recipients were retrospectively reviewed and separated into four groups: 16 cross-match negative kidney transplants, 15 cross-match positive kidney transplants, 12 cross-match negative simultaneous liver-kidney transplants, and nine cross-match–positive simultaneous liver-kidney transplants. Surveillance biopsies of cross-match–positive kidney transplants had increased expression of genes associated with donor-specific antigens, inflammation, and endothelial cell activation compared to cross-match–negative kidney transplants. These changes were not found in cross-match–positive simultaneous liver-kidney transplant biopsies when compared to cross-match–negative simultaneous liver-kidney transplants. In addition, simultaneously transplanting a liver markedly increased renal expression of genes associated with tissue integrity/metabolism, regardless of the cross-match status. While the expression of inflammatory gene sets in cross-match–positive simultaneous liver-kidney transplants was not completely reduced to the level of cross-match–negative kidney transplants, the downstream effects of donor-specific anti-HLA antibodies were blocked. Thus, simultaneous liver-kidney transplants can have a profound impact on the kidney allograft, not only by decreasing inflammation and avoiding endothelial cell activation in cross-match–positive recipients, but also by increasing processes associated with tissue integrity/metabolism by unknown mechanisms.
- gene expression
- kidney transplantation
- liver transplantation
- simultaneous liver-kidney transplantation
ASJC Scopus subject areas