Interleukin-1 receptor antagonist in ascites indicates acute graft rejection after pediatric liver transplantation

Diagnostic and predictive biomarkers of acute rejection after liver transplantation

Liver transplantation serves as a vital therapeutic intervention for individuals suffering from end-stage liver disease globally. A significant complication encountered by liver transplant recipients during the postoperative period is acute rejection, which has traditionally been identified through invasive graft biopsy procedures. Furthermore, assessing the immune status of liver transplant patients is essential for effective posttransplant management and represents a significant advancement toward the personalization of immunosuppressive therapy. Nevertheless, current immunological monitoring after the transplantation predominantly depends on clinical judgment and the measurement of immunosuppressive drug levels, lacking a comprehensive evaluation of actual immune system suppression. In contrast, biomarkers offer a comparatively novel and safer approach for the detection and prediction of transplant rejection, though their clinical application remains constrained due to the absence of prospective validation studies. This review examines the existing literature on potential biomarkers for acute rejection following liver transplantation, and their implications for clinical decision-making.

Diagnosing Acute Cellular Rejection after Paediatric Liver Transplantation-Is There Room for Interleukin Profiles?

BACKGROUND

The current gold standard to diagnose T-cell-mediated acute rejection (TCMR) requires liver histology. Using data from the ChilSFree study on immune response after paediatric liver transplantation (pLT), we aimed to assess whether soluble cytokines can serve as an alternative diagnostic tool in children suspected to have TCMR.

METHODS

A total of n = 53 blood samples obtained on the day of or up to 3 days before liver biopsy performed for suspected TCMR at median 18 days (range 7-427) after pLT in n = 50 children (38% female, age at pLT 1.8 (0.5-17.5) years) were analysed for circulating cytokine levels using Luminex-based Multiplex technology. Diagnostic accuracy of cytokine concentrations was assessed using a multivariable model based on elastic net regression and gradient boosting machine analysis.

RESULTS

TCMR was present in 68% of biopsies. There was strong evidence that patients with TCMR had increased levels of soluble CXCL8, CXCL9, CXCL10, IL-16, IL-18, HGF, CCL4, MIF, SCGF-β, and HGF before biopsy. There was some evidence for increased levels of sCD25, ICAM-1, IL-6, IL-3, and CCL11. Diagnostic value of both single cytokine levels and a combination of cytokines and clinical markers was poor, with AUROCs not exceeding 0.7.

CONCLUSION

Patients with TCMR showed raised levels of cytokines and chemokines reflective of T-cell activation and chemotaxis. Despite giving insight into the mechanisms of TCMR, the diagnostic value of soluble cytokines for the confirmation of TCMR in a clinical scenario of suspected TCMR is poor.

Cytokines in Liver Transplantation

Cytokines, soluble mediators of the immune system, play a critical role in the pathogenesis of autoimmune, allergic and infectious diseases. They are also implicated in the initiation and development of allograft rejection. During recent years, there have been considerable advances in generating novel anti-cytokine agents with promoted efficacy and safety, which could be administrated for managing dysregulated cytokine secretion; besides, gene therapy for overexpression of immunomodulatory cytokines has shown substantial improvements. Liver transplantation has been established as a life-saving treatment for end-stage hepatic diseases but the growing number of recipients urge for improved post-transplant care including tolerance induction, infection control and resolving immunosuppressant drugs adverse effects. Cytokines with a wide range of proinflammatory and regulatory properties might be considered as potential therapeutic targets for selective suppression or enhancement of the immune responses in recipients. In the present review, we aimed to summarize the positive and negative effects of cytokines on liver allograft in addition to their prognostic and therapeutic values.

Biomarkers for the diagnosis of acute cellular rejection in liver transplant recipients: A review

The gold standard for the diagnosis of acute cellular rejection (ACR) is a liver biopsy. The quest for an alternative non-invasive biomarkers has been long and is ongoing. However, an efficient and useful biomarker has not been developed yet. In this manuscript, we review all possible candidate biomarkers that have been studied in recent years, starting with cytokines and ending with an overview of different newly discovered "omics". Promising paths are being explored but a valid non-invasive biomarker has not been discovered yet.

Early expression of hepatocyte growth factor, interleukin-6, and transforming growth factor-beta1 and -beta2 in symptomatic infection in patients who have undergone liver transplantation

INTRODUCTION

Early septic complications may be a deciding factor for successful recovery among patients who have undergone orthotopic liver transplantation. Therefore, monitoring liver function parameters plays an important role in postoperative treatment to achieve an early diagnosis of postsurgical complications. We ought to measure standard liver function parameters and the expression levels for selected cytokines among patients exhibiting symptoms of infection after orthotopic liver transplantation.

MATERIALS AND METHODS

The study was performed on 30 patients who were divided into two groups: SI-0 consisted of patients free of infection, and SI-1, those who had symptoms of infection. We determined standard liver function parameters and expression of hepatocyte growth factor (HGF), interleukin (IL)-6, transforming growth factor (TGF)-beta1, and TGF-beta2.

RESULTS

There were no significant differences in standard liver function parameters between the two groups of patients. There were no significant differences in the levels of expression for the cytokines in question between the two groups of patients.

CONCLUSIONS

Although standard liver function parameters provide diagnostically valuable information on the patient's condition, they cannot be used to determine the extent of systemic infection among patients showing signs of infection after liver transplantation. Determining gene expression levels in circulating lymphocytes is a sensitive method to monitor patients' condition after liver transplantation. The expression levels of HGF, IL-6, TGF-beta1, and TGF-beta2 in circulating lymphocytes were not sufficiently specific to diagnose transitory postsurgical complications such as symptomatic infection.

Clinical significance of lymphocytes hepatocyte growth factor mRNA expression in patients after liver transplantation

Hepatocyte growth factor (HGF) plays a key role in the regulation of liver regeneration after hepatocyte damage. Changes in HGF gene expression reflect the status of the regeneration process.

AIM

The aim of this study was to ascertain the clinical significance of the expression of HGF among liver transplant patients.

METHODS

Expression of the mRNA of HGF among peripheral blood lymphocytes were measured prior to as well as at 1, 2, 6, and 10 days after liver transplantation in a group of 30 liver recipients.

RESULTS

In first 24 hours after reperfusion, the patients with compromised graft function (group 1) showed persistently higher HGF gene expression after reperfusion compared with patients displaying well-functioning grafts (group 0; P = .0189). Between postoperative days 1 and 10, there was a rapid decrease in gene expression among group 0 compared with group 1 (P = .0155). The significant decrease observed in the both groups reached a certain plateau after 48 hours postoperatively. There was no statistical difference in aminotransaminase levels over the days after liver transplantation. The decreased mRNA HGF expression in lymphocytes preceded the decrease in aminotransferase levels.

CONCLUSIONS

HGF was more sensitive to predict early graft function than prothrombin time, aspartate aminotransferase, and alanine aminotransferase levels. The determination of HGF expression level in lymphocytes after liver transplantation may yield valuable information for evaluation of early graft function.