IDENTIFICATION OF MOLECULAR BIOMARKERS IN KIDNEY DONORS OF EXTENDED CRITERIA

Abstract

Introduction. Kidney transplantation is the treatment for patients with chronic renal failure (CRF), however, the supply of organs is insufficient. Kidneys from deceased donors with extended criteria (DCE) have been increasingly used, however, the outcomes associated with the use of ECD organs are still controversial. The most commonly observed complication after transplantation from deceased donors is delayed graft function (DGF) and the mechanisms involved in its pathogenesis may be related to the release of inflammatory cytokines. Moreover, DGF is also associated with increased risk of acute rejection, lower glomerular filtration and worse graft survival in the long term. Consequently, assessing the quality of the organ through the gene expression of preimplantation biopsies profiles can provide information about the conditions of the organ to be implanted and thereby enable the development of methods to optimize the use of these "borderline" kidneys available. Thus, the evaluation of the molecular profile of kidney DCE could also assist in the understanding and prediction of DGF and its effects on the kidneys of these receptors. Evaluation of the inflammatory profile of these agencies also allow the use of strategies aimed at therapeutic interventions. Objectives. 1) To characterize the transcriptome of cytokines in kidneys obtained from standard deceased donors (DCS) and with extended criteria (DCE) in preimplantation biopsies organ (T0); 2) To correlate the cytokine profile with late graft dysfunction, cold ischemia time, acute rejection episodes and graft survival outcomes; 3) assess whether the molecular markers used as a tool for prediction of possible outcomes may be amenable instruments for use in clinical practice.Methods.: 80 kidney transplant recipients, initially divided into two groups according to the type of transplanted organ will be recruited (DCE or DCS Kidney). Biopsies preimplantation (T0) will be collected prior to coronary artery bypass graft. The molecular biology procedures comprise the steps of RNA extraction, reverse transcription by polymerase chain reaction (RT-PCR) and gene expression analysis by quantitative polymerase chain reaction in real time (qPCR) using the TaqMan Gene Expression System Array Plates genes: IL-2, IL-4, MCP-1, RANTES, IL-15, IL-18, TGF-², IL-10, IL-12, Fas-L, Granzyme B, Perforin, IFN ³, FOXP-3, Tim-3, Kim-1, CDKN1A, CDKN2A and MDR1 and two endogenous genes (GAPDH and ²-actin) to normalize the expression of mRNA. Descriptive statistical analysis will include absolute and relative frequencies for categorical variables and means, medians, standard deviation and variance for continuous variables. Comparison of categorical variables will be performed by, when appropriate chi-square or Fisher's exact test. Spearman correlation test is used to evaluate the correlation between mRNA expression levels and clinical stages. P values <0.05 are considered significant. (AU)