Serum CCL5 in Liver Transplant Candidates: A Potential Marker of Portal Hypertension, Not Cardiovascular Risk

Background: Chemokine CCL5 may drive inflammation and vascular risk in advanced liver disease, but its cardiovascular implications are unclear. Secreted by hepatic, endothelial, macrophage, and lymphocytic cells, CCL5 is involved in cytokine regulation. Its serum levels rise in acute liver injury and hepatocellular carcinoma (HCC), but decline with fibrosis progression in end-stage liver disease (ESLD). CCL5 has also been linked to atherosclerosis. This study aimed to evaluate serum CCL5 levels in ESLD patients listed for liver transplantation (LT) and to assess their potential role as markers of cardiovascular (CV) risk and portal hypertension. Methods: We conducted an observational cohort study. Between 2019 and 2022, patients with ESLD evaluated for LT were enrolled. Data on liver pathology, CV risk, and laboratory parameters were collected. Serum CCL5 concentrations were measured using Sigma Aldrich® CCL5 ELISA kits (MilliporeSigma, St. Louis, MO, USA). The database was analyzed with IBM® SPSS® Statistics version 20 (Chicago, IL, USA). Results: Overall, 46 patients were included, 50% with viral hepatitis and 28.3% with alcohol-related liver disease. HCC was present in 37% of cases. The median CV risk scores (CAD_LT = 7, mCAD_LT = 7, CAR_OLT = 18) placed the population at moderate CV risk. Serum CCL5 levels did not vary significantly between viral vs. non-viral cirrhosis (5511.8 vs. 6272.5 pg/mL, p = 0.15) and were not influenced by the presence of HCC (6098.4 vs. 5771.3 pg/mL, p = 0.55). We did not detect a correlation with MELD score (p = 0.21) or CV risk scores (CAD_LT: p = 0.58; mCAD_LT: p = 0.70; CAR_OLT: p = 0.22). Patients with thrombocytopenia (<100,000/µL, 54.3%) or a history of esophageal variceal ligation had lower CCL5 levels (5170.9 vs. 6750.8 pg/mL, p = 0.002 and 4252.0 vs. 6237.5 pg/mL, p = 0.003, respectively). Similarly, patients with a history of previous variceal bleeding and spontaneous bacterial peritonitis (SBP) had lower levels of CCL5 (4373.8 vs. 6119.9 pg/mL, p = 0.02 and 3404.3 vs. 6606.7 pg/mL, p = 0.01, respectively). We found a negative correlation between CCL5 and QTc interval duration (τ = −0.216, p = 0.037), left ventricle size (LV: τ = −0.235, p = 0.027), and pulmonary artery pressure (RV/RA gradient: τ = −0.225, p = 0.03). CCL5 correlated positively with the inflammatory markers C-reactive protein (CRP) (τ = 0.246, p = 0.018) and fibrinogen (r = 0.216, p = 0.04). Conclusions: In liver transplant candidates, serum CCL5 is not associated with cardiovascular risk scores or coronary atherosclerotic burden, but is inversely associated with clinical markers of portal hypertension severity. These findings suggest that CCL5 may serve as a potential non-invasive surrogate marker of portal hypertension rather than a cardiovascular risk biomarker in ESLD.