Arteriosclerosis Decreases Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Expression on Liver Natural Killer Cells in Living Donor Liver Transplantation

Background: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is critical for natural killer (NK) cell-mediated anti-tumor and anti-microbe killing. The TRAIL expression on the donor's liver NK cells from the liver perfusate after interleukin-2 stimulation varies between individuals and is unpredictable. This study aimed to clarify the risk factors for low TRAIL expression by analyzing perioperative donor characteristics.

Methods: This retrospective study of living donor liver transplant (LDLT) donors between 2006 and 2022 was performed to analyze low TRAIL expression risk factors. Seventy-five donors who had undergone hepatectomy for LDLT were divided into 2 groups, low and high TRAIL, according to their TRAIL expression on liver NK cells, using median values.

Results: The low TRAIL group (N = 38) was older and had lower nutrition and a higher low-density lipoprotein/high-density lipoprotein (LDL/HDL) cholesterol ratio, related to arteriosclerosis, than the high TRAIL group (N = 37). In multivariate analysis, the geriatric nutritional risk index (GNRI) (odds ratio, 0.86; 95% CI, 0.76-0.94; P < .001) and LDL/HDL cholesterol ratio (odds ratio, 2.32; 95% CI, 1.10-4.86; P = .005) were independent predictive factors for low TRAIL expression on liver NK cells. Furthermore, the TRAIL expression of liver NK cells decreased in donors who already had atherosclerosis and in donors at risk of potentially developing atherosclerosis.

Conclusions: The TRAIL expression on liver NK cells in donors had a strong relationship with atherosclerosis and GNRI. Atherosclerosis can reflect the TRAIL expression on liver NK cells.