Cytokine gene polymorphism and postreperfusion syndrome during orthotopic liver transplantation.

UNLABELLED: The molecular basis underlying the clinical response to acute liver stress remains to be clarified. Postreperfusion syndrome (PRS) occurring after the meeting of grafted liver with the recipient blood is characterized by hemodynamic instability that develops immediately after reperfusion of an orthotopic liver transplantation (OLT). Cytokines have a role during PRS. The aim of this study was to evaluate the role of some cytokine gene polymorphisms on PRS in patients. MATERIALS AND METHODS: Forty-six patients who underwent OLT were divided into two groups: with versus without PRS. Cytokine genotyping using patient blood was determined by the PCR-SSP method. RESULTS: Liver transplant patients as a whole are usually characterized as low producers of tumor necrosis factor (TNF)-alpha and interleukin (IL)-10, high producers of transforming growth factor (TGF)-beta1 and IL-6 and intermediate producers of interferon (IFN)-gamma. However no significant relationship was shown between the development of PRS and cytokine gene polymorphisms of TNF-alpha (-308 G/A), TGF-beta1 (C/T codon 10, C/G codon 25), IL-10 (-1082 G/A, -819 T/C, -592 A/C), IL-6 (-174 G/C), or IFN-gamma (+874 A/T). CONCLUSION: It seemed that our limited data did not substantiate a role of certain cytokine gene polymorphisms on PRS occurence during OLT. A larger study population may be required to examine this relationship.

Human leukocyte antigen-G, a new parameter in the follow-up of liver transplantation.

Human leukocyte antigen-G (HLA-G) displays immunotolerogenic properties toward effector cells in graft rejection through inhibition of natural killer (NK) and cytotoxic T lymphocyte (CTL)-mediated cytolysis and CD4+ T-cell alloproliferation. CD4(+)CD25(+)high regulatory T (Treg) cells are pivotal for the maintenance of self-tolerance of pathogenic alloresponses after solid organ or bone marrow transplantation in murine model systems. The aim of this study was to investigate whether there was an association between soluble and membrane-bound HLA-G levels on Treg cells and liver graft prognosis. For this purpose, we studied 37 liver transplant patients and 13 healthy blood donors. To investigate the expression of HLA-G on the surface of peripheral mononuclear (PMNL) cells, we have used monoclonal antibodies in flow cytometry to estimate CD4, CD25, CD45, and HLA-G content. HLA-G serum levels were determined by ELISA. We observed a correlation between sHLA-G serum levels and liver function tests. After a month of HLA-G decrease in serum levels, liver function tests such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), direct bilirubin (DB), total bilirubin (TB), and alkaline phosphatase (ALP) were above normal levels, suggesting liver dysfunction or rejection. Considering these results, we concluded that the increased sHLA-G in serum and on cell surfaces may afford preliminary data on the prognosis and response to treatment in liver transplant patients.

Drug interaction between capecitabine and warfarin: a case report and review of the literature.

OBJECTIVE: To report on possible adverse interaction between capecitabine and warfarin in a patient with cancer, who developed subconjunctival and nose bleeding during treatment with these drugs and review of the previously reported five cases in the literature. CASE SUMMARY: In the second week of capecitabine treatment the patient was hospitalized owing to subconjunctival hemorrhage and nose bleeding. Her international normalized ratio (INR) level was found to have increased, and both drugs were discontinued. Fresh frozen plasma replacement was administered. Warfarin and capecitabine treatment were restarted again but the warfarin dose was decreased. The patients INR was kept between 2.5-3 with the reduced dose of warfarin. DISCUSSION: Capecitabine is an orally active prodrug of fluorouracil (FU) and is extensively used as an antineoplastic agent. It is converted to 5-FU in the liver and tumor tissues. Warfarin is an antithrombolytic agent and is metabolized by liver cytochorom P450 (CYP) isoenzymes in liver. Preclinical in vitro studies using human liver microsomes report no inhibitory effects between capecitabine and substrates of CYP. However, the concomitant administration of capecitabine and warfarin resulted in gastrointestinal, retroperitoneal bleeding and hemorrhagic blisters in the five cases previously reported. The exact mechanism of this interaction is unknown; however, a significant pharmacokinetic interaction between capecitabine and S-warfarin resulting in exaggerated anticoagulant activity has recently been demonstrated. Here, we describe another case and use of the Naranjo adverse drug reaction (ADR) probability scale, which indicated a probable relationship between subconjunctival bleeding and epistaxis in this patient after concomitant warfarin and capecitabine use. CONCLUSION: Capecitabine is extensively used in outpatient clinics, and physicians should be aware of ADRs arising from combined used of capecitabine and warfarin. In the light of the current data, INR levels should be closely monitored in patients using this medication regimen.

Cytokine gene polymorphism and early graft rejection in liver transplant recipients.

Cytokines, which play important roles in allograft rejection, show variable production among individuals. These variations may be related to genetic polymorphisms within the regulatory regions of the cytokine genes. We investigated the association between the role tumor necrosis factor alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), interferon gamma (IFN-gamma), interleukin (IL)-10 and IL-6 gene polymorphisms and early graft rejection among liver transplant recipients. Forty-three liver transplant recipients enrolled in this study were divided into 2 groups based on events in the first 2 months posttransplantations, namely, those experiencing at least 1 rejection episode (n = 26) or those without any episode (n = 17). The allele or genotype frequencies of cytokine gene polymorphisms showed no difference between liver recipients with or without nonrejection. In conclusion, there was no significant correlation between early graft rejection and cytokine gene polymorphism of TNF-alpha, TGF-beta, IL-10, IL-6, and IFN-gamma in liver transplant recipients.