Kidney preservation with the UW and Euro-Collins solutions. A preliminary report of a clinical comparison

This is a preliminary report of a European Multicenter Trial of the efficacy and safety of the UW solution in kidney preservation. The results obtained with the UW solution are compared with those obtained with Euro-Collins solution in a prospectively randomized study. To date 257 patients have been evaluated, with 128 receiving kidneys preserved in UW solutions and 129 receiving kidneys preserved in Euro-Collins solutions. Demographic characteristics of donors and recipients were identical in both groups. Median (and range) preservation times were similar (24 hr in EC and 24 hr in UW). Maximum preservation time in each group was about 48 hr. The results show that the UW solution is a safe preservation solution for kidneys, with postoperative renal functions, at least, equivalent to those seen in patients transplanted with kidneys preserved in EC solution. In this preliminary analysis of 257 kidneys, use of the UW solution resulted in a more rapid reduction in postoperative serum creatinine, higher creatinine clearance rate, and less postoperative dialysis (21% vs. 31%) when compared with kidneys preserved in EC solution. This study indicates that the UW solution is an effective preservation medium for clinical kidney transplantation. It supports the use of UW solution as a general flushout and cold storage solution for all intraabdominal organs used for transplantation.     

Successful 72-hour cold storage of dog kidneys with UW solution

Effects of three cold-storage solutions on kidney function in dogs were examined with the isolated perfused (IPK) kidney model and the autotransplant model. EuroCollins' (EC) solution, phosphate-buffered sucrose solution, and a new solution developed at the University of Wisconsin (UW) were studied. Kidneys were cold-stored for 48 hr or 72 hr. With the IPK model, cold storage for 48 hr or 72 hr in each of the three solutions caused creatinine clearance to decrease by 80%-90%. More protein was excreted by kidneys stored for 48 hr in PBS solution than by kidneys stored in EC or UW solution; protein excretion after 72 hr of storage was similar for kidneys stored in EC or UW solution. Sodium reabsorption decreased after 48 hr or 72 hr of storage, but was higher in kidneys stored in UW solution (83% and 56%, respectively) than in EC solution (52% and 22%, respectively). With the autotransplant model, 40% of the kidneys were viable after 48-hr storage in PBS solution, but 80% viable when stored in EC solution and 100% were viable when stored in UW solution. All kidneys were viable when stored for 72 hr in UW solution; none were viable when stored for 72 hr in EC solution. These results suggest that UW solution effectively preserves kidneys for 72 hr. We previously reported successful 72-hr pancreas preservation. Recently UW solution was able to preserve canine livers for 30 hr. Thus, this single solution appears to be effective for preserving all intraabdominal organs and may simplify cold storage of organs for transplantation.     

Pancreas preservation with University of Wisconsin and Celsior solutions: a single-center, prospective, randomized pilot study

BACKGROUND: Celsior is an extracellular-type, low-viscosity, preservation solution already used for heart, lung, liver, and kidney transplantation. We report the results of a single-center, prospective, randomized pilot study specifically designed to compare the safety profile of Celsior solution with University of Wisconsin (UW) solution in clinical pancreas transplantation. METHODS: A total of 105 consecutive procurements were randomized to graft preservation with UW (n=53) solution or Celsior (n=52) solution. The groups were comparable with regard to all donor and recipient characteristics. RESULTS: Five grafts were discarded and 100 grafts (50 UW vs. 50 Celsior) were transplanted. Mean cold and warm ischemia times were 11.0 +/- 2.1 hr and 37.2 +/- 6.0 min for UW compared with 10.8 +/- 1.8 hr and 38.1 +/- 5.9 min for Celsior (P =not significant). Delayed endocrine pancreas function was recorded in one graft preserved with UW solution. Eleven recipients (UW 12% vs. Celsior 10%, P =not significant) required a relaparotomy. The mean serum levels of glucose, amylase, and lipase remained comparable between the study arms at equivalent intervals after transplantation. One recipient died with functioning grafts in each study arm; two further grafts were lost to arterial thrombosis (Celsior) and chronic rejection (UW), respectively. Actuarial 1-year patient and graft survival rates overlapped in the two study arms (98% and 96%, respectively). CONCLUSIONS: Within the range of cold ischemia time reported in this study, UW and Celsior solutions have similar safety profiles for pancreas preservation.     

Improved survival of orthotopic liver allograft in swine by addition of trophic factors to University of Wisconsin solution

Serum-free preservation media such as University of Wisconsin (UW) may cause tissue damage through trophic factor (TF) deprivation. This study evaluated whether the addition of TFs to UW solution improves liver graft quality after extended cold preservation time in pigs. UW solution was supplemented with epidermal growth factor, insulin-like growth factor-1, nerve growth factor-beta, bactenecin, and substance P to create TF-supplemented (TFS) UW. Orthotopic liver transplantation was performed after 18 hr of static cold storage at 4 degrees C in UW (n=7) or TFS-UW (n=7) solution. Recipients of grafts preserved with TFS-UW demonstrated significantly better 5-day survival (57%) than those preserved with UW alone (14%) (P<0.05). Adenosine triphosphate content in grafts preserved in TFS-UW was significantly higher than in grafts preserved in UW (17.4+/-5.0 vs. 4.8+/-1.2 nmol/mg protein, respectively) (P<0.05). This study showed that the addition of TFs to UW solution allowed a significant extension of cold ischemic time in pigs.     

Predictive value of liver tissue flow in assessment of the viability of liver grafts after extended preservation in pigs

The crucial damage in cold storage of liver allografts is to the hepatic sinusoidal lining (microcirculation). Using different solutions, we studied whether determinations of graft tissue flow were valuable in estimating the viability of liver grafts. Twenty-three pairs of female pigs underwent orthotopic liver transplantation and were assigned to five groups according to the cold preservation time or solutions used: in group I the liver grafts were stored in Euro-Collins solution (EC) for 4 h (n = 3), in group II the grafts were stored in EC for 12 h (n = 5), in group HI the donor was pretreated with azathioprine (AZA), 1 mg/kg per day, orally (PO) for 3 days before harvesting and the graft was implanted after 12 h cold storage with EC (n = 6), in group IV the graft was stored in modified University of Wisconsin solution (mUW) for 4 h (n = 3), and in group V the graft was stored in mUW for 24 h (n = 6). Liver tissue blood flow (LTBF) was measured, using a laser doppler device, at 60 min after recirculation of the graft. In the case of EC preservation, LTBF (ml/100 g of liver tissue per min) correlated well with 4-day survival: 21.2 ± 3.0 ml/100 g of tissue per min mean ± SD, in group I (3/3, 100%); 10.0 ± 2.8 ml/100 g of tissue per min in group II (0/5, 0%); and 19.1 ± 3.4 m1/100 g of tissue per min in group III (5/6, 83.3%) (P < 0.05, group II vs I and III). All grafts with LTBF of more than 15 ml/100 g tissue per min functioned well. However, changes in microcirculation of the mUW-stored livers did not correlate with early function of the graft: 23.0 ± 2.3 m1/100 g of tissue per min in group IV (4-day survival; 3 of 3, 100%) and 23.5 ± 9.1 m1/100 g of tissue per min in group V (0 of 6, 0%). This was accompanied by graft dehydration during storage and an increased number of erythrocytes in the hepatic sinusoids post-recirculation. We concluded that assessment of liver tissue flow by LDF was very helpful and easy to apply in predicting liver graft failure in the case of preservation with Euro-Collins solution. However, LTBF should be carefully evaluated as a marker of liver graft viability when the liver graft is preserved with mUW.     

The use of UW solution in clinical transplantation. A 4-year experience.

The development of the University of Wisconsin (UW) cold storage solution has extended safe preservation of the liver and pancreas from 6 to 24 hours or more. From May 1987 until November 1991, 288 livers and 163 simultaneous pancreas/kidney transplants were performed using UW solution. The mean preservation times were: liver, 12.7 +/- 4.4 hours, pancreas 17.2 +/- 4.4 hours, and kidney, 19.2 +/- 4.3 hours. Included in this series were 35 reduced-sized liver transplants, 7 cluster transplants, and 132 combined liver/pancreas retrievals. No differences in allograft function or graft-related complications were seen in organs preserved for less than or longer than 12 hours or in grafts from combined liver/pancreas retrievals. All pancreas/kidney transplants and most liver transplants were performed semi-electively. Actuarial 1-month patient and graft survival after liver transplantation was 91.4% and 80.2%, and at 4 years was 74.0% and 62.0%, respectively. After pancreas/kidney transplantation, the actuarial patient survival at 1 month and 4 years was 99.4% and 90.5%, respectively, whereas pancreatic and renal allograft survival at 1 month was 97.5% and 96.8%, and at 4 years was 83.0% and 83.4%, respectively. The ability to extend preservation times with UW solution has many advantages; however, the most important contribution of UW solution to clinical transplantation has been the increased utilization of scarce donor organs for more recipients because the previously imposed constraints on preservation time have been removed.     

Successful 96-Hr cold-storage preservation of canine pancreas with UW solution containing the thromboxane A2 synthesis inhibitor OKY046.

Prostanoids, such as prostacyclin (PGI) and thromboxane A2 (TxA), have been recently suggested to play an important role in preservation-induced injury of pancreas grafts. We have previously shown that the TxA synthesis inhibitor OKY046 prevents a decrease of both the PGI/TxA ratio and blood flow in pancreas grafts after 24-hr preservation with Euro-Collins solution. In our present study, we analyzed whether OKY046 added to University of Wisconsin (UW) solution could extend successful cold-storage preservation of segmental canine pancreas grafts, compared with UW alone. We divided 30 dogs into four preservation groups: Group 1, UW solution for 72 hr (n = 7); Group 2, UW solution for 96 hr (n = 8); Group 3, UW solution plus OKY046 (10(-4) M) for 72 hr (n = 7); and Group 4, UW solution plus OKY046 (10(-4) M) for 96 hr (n = 8). After the cold storage period, segmental pancreas auto-transplantation with immediate completion pancreatectomy was done. Preservation was deemed successful if serum glucose less than 150 mg/dl was maintained for at least 5 days. Intravenous glucose tolerance tests and biopsies were done in those dogs with functioning grafts 14 days post-transplant. Successful preservation rates were as follows: Group 1, 57.1%; Group 2, 12.5%; Group 3, 100%; and Group 4, 75%. The mean K values (+/- standard error) were: Group 1, 1.54 +/- 0.13; Group 2, 0.59; Group 3, 1.54 +/- 0.14; and Group 4, 1.59 +/- 0.24 (not statistically different).(ABSTRACT TRUNCATED AT 250 WORDS)     

Modulation of pulmonary NA+ pump gene expression during cold storage and reperfusion

BACKGROUND: Reperfusion injury with pulmonary edema continues to be a major complication after lung transplantation. Alveolar fluid homeostasis is regulated by Na+/K+-ATPase activity on the basolateral surface of alveolar epithelial cells. Intact Na+/K+-ATPase is essential to the resolution of pulmonary edema. We characterized the effects of cold ischemia and reperfusion on expression of Na+/K+-ATPase mRNA and protein. METHODS: Baseline values for Na+/K+-ATPase mRNA and protein were determined from freshly harvested lungs with no cold storage time or reperfusion (group I). Group II lungs were analyzed after cold storage times of 12 or 24 hr without subsequent reperfusion. Group III lungs were analyzed after cold storage times of 12 or 24 hr with subsequent reperfusion. Lungs were flushed with either Euro-Collins (EC) or University of Wisconsin (UW) solution in each group. All samples were quantified for Na+/K+-ATPase mRNA and Na+/K+-ATPase protein. Physiological parameters including oxygenation and compliance were also measured. RESULTS: There were no significant differences in the level of mRNA and protein for samples that were cold stored without reperfusion (group II). With reperfusion (group III) there was a significant increase in the level of the Na+/K+-ATPase mRNA after 12 hr of storage for both EC and UW. After 24 hr of storage and subsequent reperfusion, lungs flushed with EC had significantly decreased Na+/K+-ATPase protein and mRNA, although lungs preserved with UW maintained their increased levels of Na+/K+-ATPase protein and mRNA. CONCLUSIONS: Our data suggest that ischemia-reperfusion injury results in an initial up-regulation of Na+/K+-ATPase mRNA. With prolonged injury in lungs preserved with EC, the level of the mRNA decreased with a corresponding decrease in the Na+/K+-ATPase protein. The different response seen in EC versus UW may be explained by better preservation of pump function with UW than EC and correlates with improved physiological function in lungs preserved with UW solution.     

Evaluation of UW solution for preservation of small intestinal transplants in the rat.

Simple cold preservation was evaluated in the rat model of small intestinal transplantation. Lewis rats received a syngeneic heterotopic graft of the jejunum either immediately (SI) or after preservation for 24 hr in Euro-Collins (SPE24), for 48 hr in EC (SPE48), for 24 hr in University Wisconsin solution (SPW24), or for 48 hr in UW (SPW48). The survival rates of SI, SPE24, SPE48, SPW24, and SPW48 were 100%, 78%, 0%, 100%, and 33%, respectively. Physiologic and pharmacologic properties of the grafts and native intestine were evaluated in vitro between 8 and 12 days after transplantation. Smooth muscle in all specimens contracted in response to cholinergic agonists, phenylephrine, and substance P, and was relaxed by isoproterenol. Excitatory innervation was present in 100%, 100%, 100%, and 67% of SI, SPE24, SPW24, and SPW48, respectively, while inhibitory innervation in each group was 50%, 29%, 60%, and 0%. Thus, smooth muscle function was preserved in all groups, but neural activity was impaired by some of the storage conditions. Preservation was best in SPW24, which had physiologic responses similar to those of SI. The rat jejunum can, therefore, be preserved in good condition for up to 24 hr before transplantation using simple cold storage in UW solution.     

Intraoperative evaluation of EuroCollins and University of Wisconsin preservation solutions in patients undergoing hepatic transplantation

The effects of cold liver preservation with two solutions, EuroCollins and University of Wisconsin, were compared in terms of hepatic function and hemodynamic parameters obtained intraoperatively during orthotopic liver transplantation. Data from 101 consecutive liver transplants were analyzed retrospectively, comparing 50 grafts preserved with EC with 51 preserved with UW solution. Hepatic hemodynamics parameters included portal venous and hepatic arterial flows, determined with an electromagnetic flowmeter. Vascular pressures, blood gases and pH measurements were obtained directly from the portal vein, hepatic vein, and peripheral artery. Serial measurements of serum glucose, SGOT, and SGPT were performed following reperfusion. Preservation related graft failure occurred in 4 of 50 patients in the EC group, but not in any of 51 patients in the UW group. Cold Ischemia time (hours +/- SEM) was significantly prolonged in UW group (7.23 +/- 1.4 vs. 5.21 +/- 0.9). Rate of temperature change (degrees C/hour +/- SEM) after reperfusion was similar in both groups (EC = 0.62 +/- 0.35, UW = 0.71 +/- 0.4). Peak serum SGOT, SGPT, and glucose levels following reperfusion were significantly higher in the EC group, as was PRBC and FFP administration. Systemic hemodynamics in both groups of patients were similar. However, UW-preserved grafts demonstrated a significantly higher hepatic artery resistance, with no other differences in hepatic hemodynamics seen. UW solution appears to extend cold ischemia time without adversely affecting liver function. However, the etiology and clinical significance of the increased hepatic artery resistance seen in UW-stored liver grafts are unknown.     

Evidence that graft survival is not related to parenchymal cell viability in rat liver transplantation. The importance of nonparenchymal cells

Injury to parenchymal and nonparenchymal cells of livers stored in cold Euro-Collins solution was assessed following reperfusion and compared with graft survival following orthotopic rat liver transplantation. Parenchymal cells maintained their viability nearly completely after up to 24 hr of cold storage as assessed by trypan blue exclusion (97% of cells) and LDH release (4% of total) from livers reperfused for 20 min following storage. Furthermore, hepatic glycolysis (rates of lactate plus pyruvate production), oxygen uptake and NADH redox state (lactate:pyruvate ratio) were in the normal range at all time points studied up to 24 hr of cold storage. In contrast, nonparenchymal cells lost viability as assessed from trypan blue staining beginning after 8 hr of storage: 40% were nonviable after 24 hr of storage. Since injury to nonparenchymal cells occurs only upon reperfusion, oxygen radicals may be involved. Accordingly, xanthine and hypoxanthine, substrates for oxygen radical formation, were measured in perfusate upon reperfusion. Both purines accumulated (up to 80 microM) with time of storage and were washed out rapidly (less than 10 min) upon reperfusion. Although parenchymal cell function was in the normal range in livers stored in the cold for 24 hr, liver grafts stored for 6 hr and longer in Euro-Collins solution could not be transplanted successfully. Thus, we conclude that viability of parenchymal cells in liver grafts prior to transplantation is a poor parameter to predict the outcome of transplantation. Therefore, assessment of parenchymal cell energy state (e.g., with 31P NMR and other methods) most likely will not predict survival reliably. On the other hand, nonparenchymal cells lose their viability significantly earlier following storage and reperfusion. These data suggest that preservation of nonparenchymal cell viability is critical for successful liver transplantation.     

The impact of extended preservation on clinical liver transplantation

The introduction of UW solution into clinical transplantation has permitted extended cold storage preservation of the liver. Over a 46-month period, we have performed 308 orthotopic liver transplants (266 primary, 42 retransplants) in 266 recipients. Our experience is divided into cold-storage preservation in Eurocollins (163 transplants in 140 recipients) and UW (145 transplants in 131 recipients) solutions. Donor and recipient factors were comparable between the two groups. The use of UW solution has permitted an increase in the mean preservation time from 5.2 +/- 1.0 [EC] to 12.8 +/- 4.3 [UW] hr (P less than 0.001). The mean total operating time was reduced but intraoperative blood loss was unchanged with UW preservation. The number of transplants performed during the daytime hours has increased dramatically (21.5% [EC] vs. 71% [UW], P less than 0.001). The incidence of primary nonfunction, hepatic artery thrombosis, 1-month graft survival, and early retransplantation were similar in the 2 groups. Initial allograft function as determined by bile production, histology, and clinical assessment were likewise similar. Mean serum bilirubin, transaminase, and prothrombin levels were virtually identical by 5 days posttransplant. The enhanced margin of safety afforded by extended preservation has increased the capability for distant organ procurement and sharing, minimized organ wastage, and improved the efficiency of organ retrieval. With the relaxation of logistical constraints, our rate of liver import has nearly doubled (20.9% [EC] vs. 39.3% [UW], P less than 0.001). Extended preservation has permitted the development of reduced-size liver grafting (n = 12), resulting in a significant reduction in the number of deaths occurring while awaiting transplantation. Therefore, we advocate the use of UW solution with selective extension of preservation based not only on donor and recipient factors but also on manpower, resource, and logistical considerations.     

Amylase levels in preservation solutions as a marker of exocrine tissue injury and as a prognostic factor for pancreatic islet isolation

Occurrence of primary graft nonfunction of pancreatic islets demands research for new methods of organ preservation during cold ischemia conditions. Digestive enzymes released during preservation injure the islets for subsequent rewarming and islet isolation processes. The aim of our study was to assess the amylase level in preservation solution as a marker of exocrine tissue injury, allowing the prognosis of islet yield and viability. The experiments undertaken on rats used three commercially available preservation solutions: ViaSpan (UW); Custodiol (HTK); and Euro-Collins (EC). After 180 minutes of cold ischemia, the highest islet recovery was observed among pancreata stored in UW solution (508 +/- 139 vs HTK 344 +/- 103; P <.05 vs EC 322 +/- 113; P <.05). These islets also revealed the highest insulin stimulation index in glucose static tests (1.19 +/- 0.30 vs HTK, 0.87 +/- 0.43; P <.01, vs EC.25 +/-.06; P <.001). The highest amylase level in the preservation solution was associated with a decreased yield of islets during the isolation process and lowest insulin stimulation index (increasing 139 +/- 18% for EC, 108 +/- 12% for HTK; P <.05 vs 87 +/- 10% for UW; P <.05). Our data strongly suggest, that the dynamic of amylase release during pancreas preservation at 4 degrees C correlates with a reduced number and viability of isolated islets. These results suggest that measurement of amylase levels after pancreas preservation may have potential clinical application as a marker to evaluate pancreatic tissue injury.     

Improved preservation of the rat liver for orthotopic liver transplantation: use of University of Wisconsin-lactobionate solution and retrograde reflushing

This study investigated cold preservation and reflushing before orthotopic liver transplantation by examining (1) new University of Wisconsin solution (UW) versus Euro-Collins solution (EC), (2) retrograde reflushing (RR) versus antegrade reflushing (AR), and (3) the addition of a platelet-activating inhibitor (PAF), superoxide disumatase (SOD), or SOD + catalase to UW. Syngeneic, male Lewis rats (200 to 400 gm) were used. Preservation for 9, 12, 18, or 24 hours in UW or EC with RR (through the inferior vena cava) was used. The 9- and 12-hour groups experienced a significant decrease in the weight of the grafts preserved in UW. The 3-week survival rate after 9 hours of preservation (n = 6) in UW was 66%, and the survival rate with EC was 0% (p less than 0.025). After 12 hours of preservation, recipient survival rate was 70% (n = 10) with UW versus 0% (n = 4) with EC (p less than 0.025). RR of the graft with cold lactated Ringer's solution immediately before reimplantation significantly improved 3-week survival in the 12-hour group to the level of the control group (no preservation time, 69%). Preservation for 12 hours in UW followed by AR yielded a 3-week survival of 14%; 3-week survival for the RR group was 70% (p less than 0.025). Furthermore, RR allowed a 3-week survival of 33% and 20% after 18 and 24 hours of UW preservation, respectively. In the 24-hour RR/UW group, donor pretreatment with SRI 63-441 (20 mg/kg, intravenously) and recipient treatment with SOD (15 mg/kg, intravenously) or SOD + catalase (15 mg/kg and 5000 units/kg, intravenously) produced a 3-week survival comparable to preservation in UW followed by RR alone. These studies show that UW is a profound improvement over EC for cold preservation of liver and that the new application of RR to rat orthotopic liver transplantation improves survival. However, the addition of free-radical scavengers or PAF does not improve organ function or recipient survival in this model.     

A comparison of UW with Eurocollins preservation solution in liver transplantation

Fifty consecutive liver transplants were performed using livers perfused with and stored in University of Wisconsin preservation solution. These grafts were compared with the preceding 55 consecutive transplants performed using livers perfused and preserved with Eurocollins solution. The purpose of the study was to determine if organs preserved with UW solution functioned better after transplantation than organs preserved with Eurocollins. Extensive retrospective analysis of prospectively accumulated data included enzyme levels through 30 days, cost and length of hospital stay, blood product usage, and ischemia time. Average age of patients in the UW group was 47.1 years compared with 39.6 years in the EC group (P less than 0.05); cold ischemia time was 7.21 hr in the UW group compared with 5.21 in EC (P = 0.0001). Total bilirubin values were significantly lower on days 0-6 and day 14, but not day 30, in the UW group. Aspartate aminotransferase was significantly lower in the UW group on days 0-1, 3-6, and 14, but not on day 3 or day 30. Prothrombin times were significantly lower in the UW group across all times (days 0-6, 14, and 30). Intraoperative and postoperative use of packed red blood cells and fresh frozen plasma was lower in the UW group (P less than or equal to .05). Also, total hospital days, intensive care unit days, and hospital cost to the patient were lower in the UW group (P less than or equal to .05). A second analysis was done comparing only nonemergent transplants from both groups. These results confirmed the initial analysis of a longer cold ischemia time in the UW group (P less than 0.001), and improved enzyme values in the TBR, AST, and PT in the UW group (P less than 0.05). Also, hospital cost in the UW group was again lower (P less than 0.05). In this nonrandomized study, the cold ischemia time was increased but kept close to that of the control group. We conclude that UW solution is an improved donor liver preservation solution on the basis of improved enzyme values, decreased blood usage, shorter hospital stay, and lower hospital charges.     

Comparison of Euro-Collins and University of Wisconsin solutions in adult human cadaveric liver transplantation

To characterize the potential utility of the University of Wisconsin (UW) solution, 37 grafts preserved in UW solution (UW group) were compared with 38 grafts preserved in Euro-Collins (EC) solution (EC group). Patients in both groups underwent similar perioperative management. Donor and recipient data in the two groups were similar. The mean cold ischemia time (CIT) of the UW group was 6.51±2.06 h (range: 3.17–14.65 h); this was significantly longer than that of the EC group, of 4.80±1.68 h (range: 1.67–8.83h) (P<0.05). There were no significant differences in actuarial patient or graft survival between the two groups. Blood concentrations of aspartate aminotransferase (AST) within 12 h and lactic dehydogenase (LDH) within 6 h of reperfusion were significantly lower in the UW group than in the EC group, each being (P<0.05). The total bilirubin (TBR) concentration was lower in the UW group than in the EC group, but the difference was not significant. Alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGTP), and prothrombin time (PT) showed no significant differences between the two groups. There was no difference in the frequency of complications or rejection episodes between the two groups. However, gender identical grafts had a lower rejection than gender non-identical grafts in the UW group (P<0.05). Our data suggest that the UW solution reduces transplantation-related graft injury compared with the EC solution. Offprint requests to: T. Abe     

The influence of an improved preservation solution On prognostic factors for graft survival in pediatric liver transplantation

We investigated the influence of Eurocollins (EC) and University of Wisconson solution (UW) on prognostic factors for graft survival after pediatric liver transplantation. The 1-year graft survival was studied for 30 patients in which 38 transplantations were performed between 1982 and 1988. We preserved 19 grafts in EC and the other 19 grafts in UW solution. For grafts preserved in EC, the median preservation time was 5 h compared to 10.8 h for grafts preserved in UW solution (P < 0.01). Graft survival at 1 year was equivalent in both groups (63%). No significant differences were observed between the two groups for the following variables: patient diagnosis, child-pugh score, age, operative time, anhepatic phase, blood loss, morbidity, ICU stay, donor age and graft survival. Multivariate analysis indicated that in the EC group anhepatic phase, blood loss and preservation time were significant predictors of graft survival whereas in the UW group, none of these factors appeared to be significant. We concluded that UW was superior to EC solution in pediatric liver transplantations because it allowed longer preservation times, the length of the anhepatic phase was less important and the tolerance for blood loss seemed to be extended.     

Improved cold preservation of kidney tubular cells by means of adding bioflavonoids to organ preservation solutions

BACKGROUND: Cold ischemia and reperfusion during renal transplantation result in release of reactive oxygen species. The aim of this study is to examine whether cold storage induced cell injury can be ameliorated by adding flavonoids directly to preservation solutions. METHODS: Cultured renal tubular epithelial cells (LLC-PK1) were stored in University of Wisconsin (UW) or Euro-Collins (EC) solution at 4 degrees C for 20 hours. Preservation solutions were supplemented with various flavonoids. After rewarming, structural and metabolic cell integrity was measured by lactate dehydrogenase (LDH) release and MTT-test, and lipid peroxidation was assessed from generation of thiobarbituric acid-reactive substances (TBARS). RESULTS: Twenty hours of cold storage resulted in a substantial loss of cell viability in both preservation solutions (in EC: LDH release 92.4+/-2.7%; MTT-test 0.5+/-0.7%). Addition of luteolin, quercetin, kempferol, fisetin, myricetin, morin, catechin, and silibinin significantly reduced cell injury (for luteolin in EC: LDH release 2.4+/-1.6%; MTT-test 110.3+/-10.4%, P<0.01; TBARS-production (related to cold stored control cells) 8.9+/-2.6%). No cytoprotection was found for apigenin, naringenin, and rutin. Protective potency of flavonoids depends on number of hydroxyl-substituents and lipophilicity of the diphenylpyran compounds. CONCLUSION: Cold storage induced injury of renal tubular cells was substantially ameliorated by adding selected flavonoids directly to preservation solutions.     

Preservation of Pancreas Tissue During Cold Storage Assessed by X-Ray Microanalysis

Clinical transplantation requires cold storage of tissue for several hours. We have examined the elemental content in exocrine and endocrine cells in mouse pancreas after cold storage by X-ray microanalysis, and in parallel carried out morphological studies. Tissue was stored at 4 degrees C for 4-12 h in Normal Krebs-Ringer's (high Na+/K+ ratio), Modified Krebs-Ringer's (low Na+/K+ ratio), Euro-Collins, University of Wisconsin (UW) solution, and seven modified version of UW solution. Incubation in Normal Krebs-Ringer's solution caused significantly increased Na and decreased K concentrations in contrast to incubation in other solutions. The cellular concentration of Na and Cl followed the concentration in the storage solution. Changes in the endocrine cells were similar to, but less pronounced than those in exocrine cells. Calcium was retained best in UW and some variants of UW, and least in Euro-Collins. This may indicate differences in preservation of secretory granules. Also, morphological studies showed that endocrine cells were less affected than exocrine cells. In conclusion, the only factor determining the intracellular concentration of diffusible ions after cold tissue storage is the ionic composition of the extracellular medium. X-ray microanalysis provides an objective method to assess whether the intracellular ionic composition of tissue is maintained during storage.     

Time-related morphological changes in cold-stored rat livers. A comparison of Euro-Collins solution with UW solution

Rat livers were stored in cold UW solution and Euro-Collins solution for various periods. Morphological investigations were performed using light microscopy, as well as scanning and transmission electron microscopy. In the UW-stored livers, the appearance of blebs derived from hepatocytes and the destruction of sinusoidal endothelial cells (SEC) occurred more slowly than in the EC-stored livers. Almost no ultrastructural damage in the hepatocytes was observed even after 48 hr of storage in UW solution, while extremely swollen and degenerated hepatocytes were observed in the 48-hr EC-stored livers. After 48-hr of storage, livers stored in UW solution lost 7.9% of their weight though EC-stored livers gained 29.7% of weight. Light microscopic morphometry revealed that there was a significant increase of 24.3% in the mean hepatocyte area of 24-hr EC-stored livers, whereas the UW-stored hepatocytes did not show any significant increase even after 48 hr of storage. After perfusion fixation, livers stored for more than 8 hr in EC solution showed a mosaic pattern of uneven fixation indicating a microcirculatory disturbance, whereas the UW-stored livers showed a rather uniform fixation after 12 hr of storage. It is suggested that the microcirculatory disturbance occurred more slowly in the UW-stored livers than in the EC-stored livers, which might be due to the protection of SEC and the suppression of bleb formation and the swelling of hepatocytes by UW solution.