Activity of glutathione S-transferases in the urine of kidney transplant recipients during the first week after transplantation.

UNLABELLED: Glutathione S-Tranferases (GST) are the enzymes which are strictly specific for epithelial cells of the proximal and distal tubules in the kidney. These enzymes are detected in the urine when some tubular damage process is found. In healthy people urine GST is hardly detected. The goal of this study was to evaluate the release of two isoenzymes -- alpha and pi GST in the urine of kidney graft recipients during the first week after kidney transplantation, aiming to differentiate the cause of the delayed function (DF) of transplanted kidney. MATERIAL AND METHODS: 50 cadaveric kidneys were procured using standard technique with "in situ" cooling using UW solution. All kidneys were machine perfused. After preservation kidneys were transplanted to 50 ERSD patients. Standard triple drug immunosuppression was applied (steroids, CsA, Cell-Cept or Aza.). Graft function and the release of alpha and pi GST in the urine were measured 1, 3 and 7 days after transplantation. RESULTS: immediate function (IF) was found in 72% (36pts), DF in 28% (14pts). 5 of DF patients had ATN, 4 had acute rejection (REJ) and the remaining 5 had ATN and acute rejection (see table below). CONCLUSIONS: High alpha and pi GST concentrations were found in pts with DF graft function during the first 7 days after Tx. Elevated pi GST and low alpha GST in the urine indicates acute rejection. High alpha and pi GST in pts with DF should raise suspicion of graft rejection.

Monitoring of rat islet allografts with dithizone after induction of donor specific transplant tolerance by intrathymic administration of soluble alloantigens.

Transplantation of whole pancreas or pancreatic islets remains a promising approach to treatment of diabetes mellitus. Since there is no efficient method presently known for in vivo detection of pancreatic islet rejection, we have utilized dithizone [DTZ] to monitor the survival of transplanted islet allografts following the induction of tolerance by a new strategy of deliberate introduction of donor antigens into the adult thymus. In this study, we examined the morphology of islet allografts in vivo and in vitro following pretreatment with intrathymic (IT) inoculation of 2 mg soluble Ag obtained from 3M KCl extracts of resting T-cells with or without ALS immunosuppression in the WF-to-Lewis combination. Fresh isolated rat islets stained pink 3-5 minutes following exposure to medium containing 0.12 mM DTZ solution in DMSO. Intravenous (i.v.) injection of DTZ solution into unmodified recipients of islet allografts that had rejected their grafts showed massive degranulation of islets which did not stain pink with DTZ. This was confirmed by microscopic finding of fibrosis and lymphocytic infiltration. In contrast, i.v. injection of DTZ solution into long-term recipients of islet allografts at 50, 100, and 150 days after transplantation showed viable islet cells which stained crimson red with DTZ and the findings were confirmed with microscopic sections. This study demonstrates that DTZ is an effective means of in vivo and in vitro identification of transplanted pancreatic islets and suggests that this strategy may have potential clinical application in the diagnosis of the pancreatic islet rejection.

Expanded polytetrafluoroethylene grafts in restoring bile drainage in dogs.

Expanded polytetrafluoroethylene grafts were evaluated for use in restoring bile drainage in 21 dogs with experimental stenosis of the common bile duct. Rigid PTFE grafts reinforced with rings and armed with a polyethylene ring fastened to tissues adjacent to the hepatoduodenal ligament could not be compressed or displaced and provided a satisfactory bile drainage for periods of 12 months. Focal regeneration of common duct epithelium external to the graft was observed.

Synergistic effects of ATS and passive and active enhancement on heart and skin allografts in rats.

The effect of a combination of specific and non-specific immunosuppression on survival of heart and skin allografts in parental strain rats differing across the major histocompatibility locus was investigated. Pretreatment of the recipient with donor specific antigen and anti-donor alloantiserum prolonged the survival of heart grafts but not skin grafts. The use of antilymphocyte serum prolonged skin graft survival but not heart graft survival. However, when ATS was combined with donor specific immunosuppression, both heart and skin graft survival were prolonged dramatically. It is suggested that these treatment modalities affect differentially various aspects of the immune responses.

Microsurgical techniques in organ physiology and transplantation studies.

Experimental models for studies of physiology and pathology of different organs should be technically simple and reproducible, especially when large numbers of animals are required. Also uniform, often genetically identical, populations of animals are necessary to obtain reliable data. To meet these requirements studies should be performed on small animals. Modern microsurgical techniques help in solving these problems. The basic principles of microsurgical techniques and the microsurgical physiological and transplantation models have been described. Standardizing of techniques and models will allow better comparison of data from different centers.