Kidney injury molecule-1 staining in renal allograft biopsies 10 days after transplantation is inversely correlated with functioning proximal tubular epithelial cells.

Background: Kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) are promising biomarkers for monitoring delayed graft function (DGF) after kidney transplantation. Here we investigated localization and distribution of KIM-1 and NGAL staining in renal allograft biopsies and studied their association with histological features, functional DGF (fDGF) and the tubular function slope (TFS), a functioning proximal tubular epithelial cell (PTEC) marker.

Methods: Day 10 protocol biopsies of 64 donation after circulatory death recipients were stained for KIM-1 and NGAL and the positive area was quantified using ImageJ software.

Hematopoietic microRNA-126 protects against renal ischemia/reperfusion injury by promoting vascular integrity.

Ischemia/reperfusion injury (IRI) is a central phenomenon in kidney transplantation and AKI. Integrity of the renal peritubular capillary network is an important limiting factor in the recovery from IRI. MicroRNA-126 (miR-126) facilitates vascular regeneration by functioning as an angiomiR and by modulating mobilization of hematopoietic stem/progenitor cells.

Acute but transient release of terminal complement complex after reperfusion in clinical kidney transplantation.

Background: Ischemia/reperfusion (I/R) injury has a major impact on kidney graft function and survival. Animal studies have suggested a role for complement activation in mediating I/R injury; however, results are not unambiguous. Whether complement activation is involved in clinical I/R injury in humans is still unclear.

Pitfalls in urinary complement measurements.

Local activation of the complement system has been associated with ischemia/reperfusion injury following kidney transplantation and tubular injury under proteinuric conditions. The soluble terminal complement complex sC5b-9 is a stable end-product of the complement cascade, and as such a promising urinary biomarker. In the early post-transplant period we found high urinary levels of sC5b-9, significantly correlating with the degree of proteinuria, suggesting activation of filtered complement components at the tubular epithelial surface of the kidney.