To improve the evolution of transplants we need to identify risk biomarkers of morbidity and loss of allograft. In liver transplant (LTX) recipients, an association has been demonstrated between the presence of mismatch for glutathione S-transferase T1 (GSTT1) and the development of de novo immune hepatitis (IH). The differences in the genotypes of codifying metabolic enzymes between donors and recipients seem to be a prognostic biomarker in order to identify individuals at risk of complication following liver transplantation (LTX). According to previous studies if the patient is null phenotype and the donor is positive (GSTT1 Mismatch) then the patient should be monitored in the long-term for development of atypical auto antibodies and the appearance of de novo Immune hepatitis and graft dysfunction. Atypical auto antibodies have been shown to be directed to the enzyme GSTT1, a 29-kDa molecular weight protein, expressed abundantly in the liver and kidney. The aim of this study was to determine the prevalence of GSTT1 genotype in the Iranian population, who had LTX from august 2007 to May 2008 in the Organ Transplantation Center affiliated with Shiraz University of Medical Sciences. Determination of GSTT1 in 54 recipients was carried out by an assay based on internal standard controlled polymerase chain reaction (PCR). DNA from the peripheral blood samples of subjects with positive GSTT1 alleles yielded amplification of a 492-bp fragment. As a positive control a fragment of beta- globin was also amplified. Half of our patients (27/54) had null genotype. This is a high prevalence. But determination of GSTT1 genotype in both donors and recipients are important because it was previously confirmed that only with one of the four possible genetic combinations (null recipient/positive donor), an alloimmune response triggers the production of anti-GSTT1 antibodies. Our study is a preliminary report and further research is required in order to elucidate whether in LTX recipients with GSTT1 mismatch, anti-GSTT1 antibodies will be produced and an alloimmune reaction targeted at the allograft will lead to post transplantation IH or not.
Volume : 6
Issue : 4
Pages : 163
Transplantation Research center, Shiraz University of Medical Sciences, Shiraz, Iran