Leukocyte adhesion molecules in transplantation

Is urine intercellular adhesion molecule-1 a marker of renal disorder in children with ureteropelvic junction obstruction?

AIM

We aimed to investigate whether urine intercellular adhesion molecule-1 (ICAM-1) might serve as a marker of renal disorder in children with ureteropelvic junction obstruction.

MATERIAL AND METHODS

Twenty-nine children with severe hydronephrosis (HN) were compared with 23 participants with mild HN and with 19 healthy peers.

RESULTS

Urine ICAM-1/uCre levels were significantly higher in HN children than healthy controls (P<0.01), and in severe HN when compared with mild HN (p<0.05).

CONCLUSIONS

It seemed to us that uICAM-1 is a biomarker of renal disorder, and might have the potential to predict which patients will require surgery.

Correlation between ICAM1 and VCAM1 gene polymorphisms and histopathological changes in kidney allograft biopsies

INTRODUCTION

The immunoglobulin-like molecules intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) are responsible for endothelial cell-leukocyte adhesion followed by transmigration of leukocytes through the endothelial cell lining. The aim of this study was to examine the correlation between polymorphisms in ICAM1 and VCAM1 genes and histopathological changes in transplanted kidney biopsies.

MATERIAL AND METHODS

The study enrolled 82 Caucasian renal transplant recipients (48 males, 34 females). Genotyping of the rs5498 ICAM1 and the rs1041163 and rs3170794 VCAM1 gene polymorphisms was performed using real-time polymerase chain reaction (PCR). Biopsies were performed in 82 patients and were reviewed by a renal pathologist and the Banff working classification criteria were used.

RESULTS

There were no significant associations between VCAM gene polymorphisms and histopathological changes in kidney allograft biopsies. ICAM1 gene polymorphism was associated with the grade of interstitial fibrosis. Interstitial fibrosis was more severe among individuals with the G allele than those with the A allele (AA vs. GG+AG, p = 0.017). There were no statistically significant associations between ICAM1 gene polymorphism and other histopathological changes in kidney allograft biopsies.

CONCLUSIONS

The results of our study suggest that rs5498 ICAM1 gene polymorphism is associated with the grade of interstitial fibrosis in kidney recipients and the changes are more severe in patients with the G allele.

Dedifferentiation and proliferation of surviving epithelial cells in acute renal failure

In contrast to the heart or brain, the kidney can completely recover from an ischemic or toxic insult that results in cell death. During recovery from ischemia/reperfusion injury, surviving tubular epithelial cells dedifferentiate and proliferate, eventually replacing the irreversibly injured tubular epithelial cells and restoring tubular integrity. Repair of the kidney parallels kidney organogenesis in the high rate of DNA synthesis and apoptosis and in patterns of gene expression. As has been shown by proliferating cell nuclear antigen and 5-bromo 2'-deoxyuridine labeling studies and, in unpublished studies, by counting mitotic spindles identified by labeling with antitubulin antibody, the proliferative response is rapid and extensive, involving many of the remaining cells of the proximal tubule. This extensive proliferative capacity is interpreted to reflect the intrinsic ability of the surviving epithelial cell to adapt to the loss of adjacent cells by dedifferentiating and proliferating. Adhesion molecules likely play important roles in the regulation of renal epithelial cell migration, proliferation, and differentiation, as do cytokines and chemokines. Better understanding of all of the characteristics resulting in dedifferentiation and proliferation of the proximal tubule epithelial cell and cell-cell and cell-matrix interactions important for this repair function will lead to novel approaches to therapies designed to facilitate the processes of recovery in humans.

The endothelium in clinical cardiac transplantation

Cardiac transplantation is the most successful therapy for refractory heart failure, but clinical transplantation is still confronted with the problems of acute rejection and acute pump failure. The limiting factor in achieving prolonged survival remains cardiac allograft vasculopathy. In recent years it has become apparent that from brain death onward, the cardiac endothelium plays a key role in these acute and chronic events. Brain death is associated with an inflammatory response that primes the endothelium for cumulative injury during the subsequent stages of ischemic cold storage, reperfusion and allorecognition. As a structural and functional interface, the endothelium is the site at which inflammatory cells move from the bloodstream through the vessel wall into the parenchyma. The endothelium interacts with the complement system, the coagulation and inflammatory cascades, circulating leukocytes, the immune system, the smooth muscle in the vessel wall, and the surrounding matrix and cardiomyocytes. A better understanding of its many roles may lead to expansion of our therapeutic possibilities and better outcomes overall. This article reviews the possible roles of the endothelium in relation to cardiac transplantation, and discusses the diagnostic and therapeutic modalities that are available to date.

Interleukin-10 inhibits ischemic and cisplatin-induced acute renal injury

BACKGROUND

Acute renal failure (ARF) is caused by ischemic and nephrotoxic insults acting alone or in combination. Anti-inflammatory agents have been shown to decrease renal ischemia-reperfusion and cisplatin-induced injury and leukocyte infiltration. Interleukin-10 (IL-10) is a potent anti-inflammatory cytokine that inhibits inflammatory and cytotoxic pathways implicated in acute renal injury. Therefore, we sought to determine if IL-10 inhibits acute renal injury.

METHODS

The effects of IL-10 were studied in mice following cisplatin administration and bilateral renal ischemia-reperfusion, in a rat model of renal transplantation, and in cultured mouse cortical tubule cells.

RESULTS

IL-10 significantly decreased renal injury following cisplatin administration and following renal ischemia/reperfusion. Delay of IL-10 treatment for one hour after cisplatin also significantly inhibited renal damage. IL-10 and alpha-melanocyte stimulating hormone (alpha-MSH) increased recovery following transplantation of a kidney subjected to warm ischemia. To explore the mechanism of action of IL-10, its effects were measured on mediators of leukocyte trafficking and inducible nitric oxide synthase (NOS-II). IL-10 inhibited cisplatin and ischemia-induced increases in mRNA for tumor necrosis factor-alpha (TNF-alpha), intercellular adhesion molecule-1 (ICAM-1), and NOS-II. IL-10 also inhibited staining for markers of apoptosis and cell cycle activity following cisplatin administration, and nitric oxide production in cultured mouse cortical tubules.

CONCLUSIONS

IL-10 protects against renal ischemic and cisplatin-induced injury. IL-10 may act, in part, by inhibiting the maladaptive activation of genes that cause leukocyte activation and adhesion, and induction of iNOS.

New perspectives for prevention/treatment of acute renal failure

Acute renal failure continues to be a difficult clinical problem in critically ill patients, despite advances in critical care and dialysis. This review focuses on some of the current issues in the nondialytic and dialytic management of these patients. Critical analysis of some still frequently used drugs in these patients such as diuretics and dopamine in so-called 'renal doses' has revealed little beneficial effect. Recent data are in conflict with previous suggestions that biocompatible membranes have a positive effect on the recovery of renal function and on patient mortality. The choice between intermittent haemodialysis and continuous renal replacement therapy should be made on an individual basis and not on the basis of 'dogmatic' opinion.