Search

The continuous evolution of metabolomics over the past two decades has stimulated the search for metabolic biomarkers of many diseases. Metabolomic data measured from urinary samples can provide rich information of the biological events triggered by organ rejection in pediatric kidney transplant recipients. With additional validation, metabolic markers can be used to build clinically useful diagnostic tools. However, there are many methodological steps ranging from data processing to modeling that can influence the performance of the resulting metabolomic classifiers. In this study we focus on the comparison of various classification methods that can handle the complex structure of metabolomic data, including regularized classifiers, partial least squares discriminant analysis, and nonlinear classification models. We also examine the effectiveness of a physiological normalization technique widely used in the clinical and biochemical literature but not extensively analyzed and compared in urine metabolomic studies. While the main objective of this work is to interrogate metabolomic data of pediatric kidney transplant recipients to improve the diagnosis of T cell‐mediated rejection (TCMR), we also analyze three independent datasets from other disease conditions to investigate the generalizability of our findings. [ABSTRACT FROM AUTHOR]

Ushigome H, Okamoto M, Koshino K, Nobori S, Okajima H, Masuzawa N, Urasaki K, Yoshimura N. Findings of graft biopsy specimens within 90 days after ABO blood group incompatible living donor kidney transplantation compared with ABO-identical and non-identical transplantation. Clin Transplant 2010: 24 (Suppl. 22): 16–21. © 2010 John Wiley & Sons A/S. As immunosuppressive therapy has advanced, we have markedly improved the outcome of ABO blood group incompatible living donor kidney transplantation. Consequently, graft survival at early phase after ABO-incompatible transplantation has been favorable than ABO-compatible transplantation in Japan. But in these days, it has been assumed that transplant glomerulopathy within one yr after ABO-incompatible kidney transplantation might be significantly precipitated. That may be because of chronic, active antibody-mediated rejection (AMR). We performed kidney graft biopsies at the early phase within 90 d after living donor kidney transplantation that involved the episode and protocol biopsies and studied findings of graft biopsy specimens when compared with ABO incompatible and compatible involving non-identical and identical transplantations. In ABO-incompatible transplant cases, the ratio occurring glomerulitis, especially severe injury of g 2–3, was significantly higher than that of identical and non-identical transplant cases (p < 0.01). There was no significant difference in t score, i score, ptc score and v score between three transplant groups. The cases occurring AMR were concordant with the cases recognized with severe glomerulitis. AMR was difficult to be diagnosed by C4d analysis in ABO-incompatible transplant cases. Glomerular injury score, g score, may be considered as more significant and the injury should be cured thoroughly. [ABSTRACT FROM AUTHOR]