Value of Fractalkine and soluble CD40 ligand in bile in predicting liver injury after liver transplantation / 临床肝胆病杂志

ABSTRACT

Objective To investigate the value of cytokines in bile combined with clinical indices in predicting the degree of liver injury after liver transplantation. MethodsA total of 16 patients undergoing liver transplantation who were hospitalized in Center of Organ Transplantation, The Affiliated Hospital of Qingdao University, from January to December 2018 were enrolled, and according to the level of alanine aminotransferase (ALT) on day 1 after surgery, the patients were divided into mild liver injury (ALT ＜500 U/L) group with 10 patients and severe liver injury (ALT ＞500 U/L) group with 6 patients. Bile samples were collected on days 1, 3, 5, and 7 after surgery, and MILLIPLEX assay was used to measure the levels of 17 cytokines. R software was used to perform principal component analysis (PCA) of bile cytokines and clinical indices and gene ontology (GO) enrichment analysis of bile cytokines. The two-independent-samples t-test was used for comparison of normally distributed continuous data between two groups; The Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups. A Spearman correlation analysis was performed to evaluate the correlation between clinical indices and bile cytokines. ROC curve analysis was used to evaluate the predictive value of cytokines in bile and clinical indices for liver injury after liver transplantation. ResultsCompared with the mild liver injury group, the severe liver injury group had significantly higher expression levels of bile Fractalkine (Z=-2.828, P=0.003), soluble CD40 ligand (sCD40L) (Z=-2.850, P=0.008), interleukin-4 (Z=-2.398, P=0.017), CXCL10 (Z=-2.475, P=0.023), and macrophage inflammatory protein-1α (Z=-1844, P=0.043). The correlation analysis showed that on day 1 after liver transplantation, aspartate aminotransferase, ALT, and lactate dehydrogenase were positively correlated with the levels of several cytokines in bile (all P＜0.05). The area under the ROC curve of Fractalkine, sCD40L and AST were 0.933 (0.812-1.000), 0.833 (0.589-1.000) and 0.917 (0.779-1.000), respectively, suggesting that AST and Fractalkine and sCD40L in bile on the first day after liver transplantation have significant predictive value for liver injury. The results of PCA showed that bile cytokines combined with clinical indices on day 1 after liver transplantation could better distinguish the patients with mild liver injury from those with severe liver injury. GO analysis showed that bile cytokines were associated with positive feedback regulation of external stimulus, cell chemotaxis, receptor ligand activity, cytokine activity, and cytokine-cytokine receptor interaction. ConclusionFractalkine and sCD40L in bile can predict the degree of liver injury after liver transplantation.