Project description:Kidney transplantation is the treatment of choice for patients with end-stage chronic kidney disease (ESKD). Despite the usefulness of transplantation as replacement therapy, long-term graft survival represents a major challenge for transplant immunology. Although nowadays there has been an advance in understanding immunological mechanisms mediating rejection, and the improvement of immunomodulation therapies, there are still underlying molecular processes marking an important variability among patients, and presumably influencing allograft rejection. With our analysis we explored differences in gene expression by Next Generation Sequencing implementing RNA-Seq in biopsies, blood and urine from kidney transplant patients with acute and chronic rejection. For this, we performed an intra-outcome analysis simultaneously in acute and chronic rejection, with which we sought: 1. To identify differences in gene expression between peripheral blood vs renal tissue and peripheral blood vs urine in acute rejection and chronic rejection; 2. To identify the level of agreement in gene expression between renal tissue and urine in acute rejection and chronic rejection and 3. To identify genes and biological processes associated with acute rejection and chronic rejection that could be potentially detected in blood, and simultaneously in urine and biopsy in acute rejection and in chronic rejection.
Project description:The post kidney transplant period is associated with insulin resistance partly due to corticosteroids. Patients on minimal corticosteroid therapy receiving tacrolimus (FK506) for immunosuppression also are affected. FK506 inhibits calcineurin in immune cells. Skeletal muscle calcineurin, which also might be inhibited, mediates exercise-induced transcription leading to more insulin-sensitive muscle. This study was performed to determine if gene transcription responses to exercise are lower in patients awaiting kidney transplant or 3 months post-transplant on a low-steroid, FK506 protocol.
Project description:Treatment with angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) has been shown to have anti-inflammatory effects such as decreased growth factors and cytokines in animal models, this effect however, has not been investigated in kidney transplant recipients. We aimed to study the effect of ACEI or ARB treatment on intragraft gene expression profiles of transplant kidney biopsies using microarrays. Both groups had similar demographic characteristics in terms of age, race, sex, type of transplant, previous history of transplantation or acute rejection, panel reactive antibody levels, and immunosuppressive treatment. There were no differences in acute and chronic Banff allograft injury scores between the 2 Groups. Intragraft gene expression profiles of ACEI or ARB treated Group 2 biopsies showed decreased gene transcripts of interferon-gamma and rejection-associated transcripts (GRIT) and constitutive macrophage-associated transcripts (CMAT) compared to Group 1 biopsies. There were no statistically significant differences in expression of cytotoxic T cell (CAT), regulatory T cell (TREG), B-cell (BAT), natural killer cell (NKAT), or endothelial cell-associated transcripts (ENDAT) between the 2 Groups. Our data suggest that exposure to ACEI or ARB was associated with down-regulation of GRIT and CMAT. This anti-inflammatory effect of ACEI or ARB treatment could be an additional benefit in kidney transplant recipients. We identified 29 near normal biopsies with chronic sum allograft injury score (ct+ci+cv) ⤠3 for gene expression profiling comparing 2 groups; Group 1 (n=16), patients with no exposure of ACEI or ARB treatment and Group 2 patients (n=13) with exposure to ACEI or ARB at least 6 months prior to kidney biopsy. Biopsies with a diagnosis of acute or chronic rejection, recurrent or de novo glomerular disease, or polyoma nephropathy were excluded.
Project description:Early development of acute rejection after kidney transplantation is associated with diminished long-term graft survival. Predicting early acute rejection (EAR) at the time of transplant is important to risk-stratify patients and titrate immunosuppression accordingly. We performed whole-blood RNA sequencing at the time of transplant in 235 kidney transplant recipients enrolled in a prospective-cohort study [one discovery set (N=81), two validation sets (N=74 and N=80)] and evaluated the relationship with EAR and graft loss. We identified a blood based 23-gene set in recipients at the time of transplant that predicts the risk of EAR and is associated with late AR and allograft loss. This gene set is an important new tool to risk-stratify recipients before kidney transplantation and help guide immunosuppressive therapy accordingly.
Project description:Gene expression data was analyzed to map with urine proteomics data gene expression data from kidney biopsies from kidney transplant patients with and without acute rejection, chronic allograft nephropathy and BK virus nephritis was used to study gene expression changes during acute rejection, chronic allograft nephropathy and bk virus nephropathy. Samples labeled STA16, STA22, STA14, and STA18 were included in the CAN vs no-CAN analysis as no-CAN samples as they also qualified as non-CAN samples.