High levels of C-reactive protein after simultaneous pancreas-kidney transplantation predict pancreas graft-related complications and graft survival

Exploring definitions of graft pancreatitis following pancreas transplantation: A scoping review

Despite the clinical relevance of graft pancreatitis (GP) after pancreas transplantation (PT), a universally accepted definition is lacking. Aim of this scoping review was to provide a systematic overview of GP definitions reported in the literature. MEDLINE, Web of Science and Embase were searched for relevant articles. Prospective/retrospective studies reporting a GP definition were included. The included series (n = 20) used four main criteria (clinical, biochemical, radiological and pathological) to define GP. Overall, 9 studies defined GP using a single criterion (n = 8 biochemical, n = 1 pathological), 7 series using two criteria (n = 3 clinical + biochemical, n = 3 biochemical + radiological, n = 1 clinical + radiological), 3 series using three criteria (n = 3 clinical + biochemical + radiological), and 1 series using four criteria. Overall, 20 definitions of GP were found. GP rate was reported by 19 series and ranged between 0% and 87%. This scoping review confirms that a universally accepted definition of GP is absent, and there is no consensus on the criteria on which it should be grounded. Future research should focus on developing a validated definition of GP.

Impact of Pretransplant C-Reactive Protein, Neutrophiles, Platelets, and Albumin Levels on Recipient Survival After Simultaneous Pancreas and Kidney Transplantation

BACKGROUND

Long-lasting diabetes mellitus type 1 and end-stage renal disease induce severe metabolic and immunologic deterioration. Pretransplant C-reactive protein (CRP) and albumin (ALB) levels impact kidney transplantation. We evaluated the effects of preoperative CRP, ALB, neutrophils (NEU), and platelet (PLT) counts on 1- and 5-year recipient survival after simultaneous pancreas and kidney transplantation (SPK).

METHODS

Among 103 SPK recipients, the parameters were as follows: CRP (mean: 4.5 ± 4.97 mg/L); NEU (mean: 5.12 ± 2.13 × 103/mm3); PLT (mean: 244 ± 84 × 103/mm3); ALB (mean 4.5 ± 0.75 g/dL) were obtained before transplantation. Cox regression, uni-, multivariate analysis for 1- and 5-year survivals were performed with 95% CIs, and the area under the receiver operating characteristic (ROC) curve (AUC) was assessed.

RESULTS

In Cox regression, ALB <3.65 g/dL significantly affected 1- and 5-year survivors with hazard ratios of 8 (95% CI, 1.5-38.28; P < .05) and 3.13 (95% CI, 1.45-6.73; P < .05), respectively. In univariate analysis, we found significantly decreased 1-year survival when PLT <180×103/mm3, ALB <3.65 g/dL, NEU >5.8×103/mm3 and CRP >2.25 mg/L with odds ratios (OR) of 6.75 (95% CI, 2.12-21.15); 4.05 (95% CI, 1.3-12.09); 2.97 (95% CI, 1.02-8.64) and 5.51 (95% CI, 1.67-18.19), respectively. Independent factors for 5-year survival were CRP, ALB, and PLT with OR of 4.72 (95% CI, 1.67-13.29), 3.31 (95% CI, 1.18-9.25), and 4.2 (95% CI, 1.39-12.68), respectively. In multivariate analysis, we built 2 models for 1-year survival. Model 1 (ALB+PLT) with ORs of 3.12 (95% CI, 0.97-10.07) and 5.55 (95% CI, 1.67-18.4); and model 2 (CRP+PLT) with ORs of 5.51 (95% CI, 1.5-17.3) and 4.3 (95% CI, 1.2-15.06), respectively. The AUC for models 1 and 2 were 0.74 and 0.759, respectively.

CONCLUSIONS

NEU, PLT, ALB, and CRP levels assessed before transplantation are independent factors for 1- and 5-year SPK recipient survival.

Thromboinflammatory response is increased in pancreas transplant alone versus simultaneous pancreas-kidney transplantation and early pancreas graft thrombosis is associated with complement activation

BACKGROUND

Pancreas transplant alone (PTA) recipients are more affected by pancreas graft thrombosis, and graft loss compared to simultaneous pancreas-kidney (SPK) recipients. The pathophysiology is unknown, but an increased immune response has been suggested in the PTA recipients. In this observational study, we compared perioperative thromboinflammation between PTA (n=32) and SPK (n=35) recipients, and between PTA recipients with (n=14) versus without (n=18) early graft thrombosis.

METHODS

We measured C-reactive protein (CRP), plasma markers of activated coagulation and complement, and cytokines preoperatively and daily during the first postoperative week.

RESULTS

Preoperatively, coagulation and complement activation markers were comparable between PTA and SPK recipients, while cytokine concentrations were higher in SPK recipients (TNF, IL-8, IP-10, MCP-1, MIP-1α; all p<0.05). On the first postoperative day, PTA recipients had higher coagulation activation, measured as thrombin-antithrombin complex (TAT), than SPK recipients (p=0.008). In the first postoperative week, PTA recipients showed higher relative cytokine release (IL-6, IL-8, G-CSF, IP-10, MCP-1, and MIP-1α; all p<0.05) while SPK recipients showed higher absolute cytokine concentrations (TNF, IL-1ra, IL-8, MIP-1α, and IL-4; all p<0.05). PTA and SPK recipients showed similar terminal complement complex (TCC, sC5b-9) activation. On the first postoperative day, TCC (OR 1.2 [95% CI 1.0-1.5] for 0.1 CAU/ml increase, p=0.02) and CRP (OR 1.2 [95% CI 1.0-1.3] for 10 mg/L increase, p=0.04) were associated with an increased risk of early graft thrombosis. TCC was specific for graft thrombosis, while CRP increased with several complications. PTA recipients with compared to those without graft thrombosis had higher TCC pre- (p=0.04) and postoperatively (p=0.03).

CONCLUSION

The relative increase in postoperative thromboinflammatory response was more pronounced in PTA recipients. Complement activation was associated with an increased risk of graft thrombosis. This study indicates that innate immune activation rather than elevated levels may affect early postoperative pancreas graft thrombosis.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT01957696, identifier NCT01957696.

Analysis of Volatile Anesthetic-Induced Organ Protection in Simultaneous Pancreas-Kidney Transplantation

BACKGROUND

Despite recent advances in surgical procedures and immunosuppressive regimes, early pancreatic graft dysfunction, mainly specified as ischemia-reperfusion injury (IRI)-Remains a common cause of pancreas graft failure with potentially worse outcomes in simultaneous pancreas-kidney transplantation (SPKT). Anesthetic conditioning is a widely described strategy to attenuate IRI and facilitate graft protection. Here, we investigate the effects of different volatile anesthetics (VAs) on early IRI-associated posttransplant clinical outcomes as well as graft function and outcome in SPKT recipients.

METHODS

Medical data of 105 patients undergoing SPKT between 1998-2018 were retrospectively analyzed and stratified according to the used VAs. The primary study endpoint was the association and effect of VAs on pancreas allograft failure following SPKT; secondary endpoint analyses included "IRI- associated posttransplant clinical outcome" as well as long-term graft function and outcome. Additionally, peak serum levels of C-reactive protein (CRP) and lipase during the first 72 h after SPKT were determined and used as further markers for "pancreatic IRI" and graft injury. Typical clinicopathological characteristics and postoperative outcomes such as early graft outcome and long-term function were analyzed.

RESULTS

Of the 105 included patients in this study three VAs were used: isoflurane (n = 58 patients; 55%), sevoflurane (n = 22 patients; 21%), and desflurane (n = 25 patients, 24%). Donor and recipient characteristics were comparable between both groups. Early graft loss within 3 months (24% versus 5% versus 8%, p = 0.04) as well as IRI-associated postoperative clinical complications (pancreatitis: 21% versus 5% versus 5%, p = 0.04; vascular thrombosis: 13% versus 0% versus 5%; p = 0.09) occurred more frequently in the Isoflurane group compared with the sevoflurane and desflurane groups. Anesthesia with sevoflurane resulted in the lowest serum peak levels of lipase and CRP during the first 3 days after transplantation, followed by desflurane and isoflurane (p = 0.039 and p = 0.001, respectively). There was no difference with regard to 10-year pancreas graft survival as well as endocrine/metabolic function among all three VA groups. Multivariate analysis revealed the choice of VAs as an independent prognostic factor for graft failure three months after SPKT (HR 0.38, 95%CI: 0.17-0.84; p = 0.029).

CONCLUSIONS

In our study, sevoflurane and desflurane were associated with significantly increased early graft survival as well as decreased IRI-associated post-transplant clinical outcomes when compared with the isoflurane group and should be the focus of future clinical studies evaluating the positive effects of different VA agents in patients receiving SPKT.

Correlation of Different Serum Biomarkers with Prediction of Early Pancreatic Graft Dysfunction Following Simultaneous Pancreas and Kidney Transplantation

Background: Despite recent advances and refinements in perioperative management of simultaneous pancreas−kidney transplantation (SPKT) early pancreatic graft dysfunction (ePGD) remains a critical problem with serious impairment of early and long-term graft function and outcome. Hence, we evaluated a panel of classical blood serum markers for their value in predicting early graft dysfunction in patients undergoing SPKT. Methods: From a prospectively collected database medical data of 105 patients undergoing SPKT between 1998 and 2018 at our center were retrospectively analyzed. The primary study outcome was the detection of occurrence of early pancreatic graft dysfunction (ePGD), the secondary study outcome was early renal graft dysfunction (eRGD) as well as all other outcome parameters associated with the graft function. In this context, ePGD was defined as pancreas graft-related complications including graft pancreatitis, pancreatic abscess/peritonitis, delayed graft function, graft thrombosis, bleeding, rejection and the consecutive need for re-laparotomy due to graft-related complications within 3 months. With regard to analyzing ePGD, serum levels of white blood cell count (WBC), C-reactive protein (CRP), procalcitonin (PCT), pancreatic lipase as well as neutrophil−lymphocyte ratio (NLR) and platelet−lymphocyte ratio (PLR) were measured preoperatively and at postoperative days (POD) 1, 2, 3 and 5. Further, peak serum levels of CRP and lipase during the first 72 h were evaluated. Receiver operating characteristics (ROC) curves were performed to assess their predictive value for ePGD and eRGD. Cut-off levels were calculated with the Youden index. Significant diagnostic biochemical cut-offs as well as other prognostic clinical factors were tested in a multivariate logistic regression model. Results: Of the 105 patients included, 43 patients (41%) and 28 patients (27%) developed ePGD and eRGD following SPKT, respectively. The mean WBC, PCT, NLR, PLR, CRP and lipase levels were significantly higher on most PODs in the ePGD group compared to the non-ePGD group. ROC analysis indicated that peak lipase (AUC: 0.82) and peak CRP levels (AUC: 0.89) were highly predictive for ePGD after SPKT. The combination of both achieved the highest AUC (0.92; p < 0.01) in predicting ePGD. Concerning eRGD, predictive accuracy of all analyzed serological markers was moderate (all AUC < 0.8). Additionally, multivariable analysis identified previous dialysis/no preemptive transplantation (OR 2.4 (95% CI: 1.41−4.01), p = 0.021), donor age (OR 1.07 (95% CI: 1.03−1.14), p < 0.010), donor body mass index (OR 1.32 (95% CI: 1.01−1.072), p = 0.04), donors cerebrovascular cause of death (OR 7.8 (95% CI: 2.21−26.9), p < 0.010), donor length of ICU stay (OR 1.27 (95% CI: 1.08−1.49), p < 0.010), as well as CIT pancreas (OR 1.07 (95% CI: 1.03−1.14), p < 0.010) as clinical relevant prognostic predictors for ePGD. Further, a peak of lipase (OR 1.04 (95% CI: 1.02−1.07), p < 0.010), peak of CRP levels (OR 1.12 (95% CI: 1.02−1.23), p < 0.010), pancreatic serum lipase concentration on POD 2 > 150 IU/L (OR 2.9 (95% CI: 1.2−7.13), p = 0.021) and CRP levels of ≥ 180 ng/mL on POD 2 (OR 3.6 (95% CI: 1.54−8.34), p < 0.01) and CRP levels > 150 ng/mL on POD 3 (OR 4.5 (95% CI: 1.7−11.4), p < 0.01) were revealed as independent biochemical predictive variables for ePGD after transplantation. Conclusions: In the current study, the combination of peak lipase and CRP levels were highly effective in predicting early pancreatic graft dysfunction development following SPKT. In contrast, for early renal graft dysfunction the predictive value of this parameter was less sensitive. Intensified monitoring of these parameters may be helpful for identifying patients at a higher risk of pancreatic ischemia reperfusion injury and various IRI- associated postoperative complications leading to ePGD and thus deteriorated outcome.

Serum pancreatic enzymes in the early postoperative period predict complications associated with pancreatic fluid after pancreas transplantation: A retrospective, single-center, observational cohort study

BACKGROUND

Pancreas transplantation (PT) is a radical treatment for diabetes mellitus (DM). Although the results of PT have been improving, surgical complications remain. Few reports have focused on complications associated with pancreatic fluid (CAPF) after PT. We aimed to investigate the risk factors and predictors for CAPF after PT.

METHODS

Sixty-nine patients, who underwent deceased-donor PT for type 1 DM at our institution from August 2001 to May 2020, were retrospectively studied. We identified CAPF from those with Clavien-Dindo Classification ≥grade III and assessed risk factors by univariate and multivariate analyses using logistic regression.

RESULTS

Twenty-one (30.4%) patients had complications with Clavien-Dindo Classification ≥grade III. Eleven (16.0%) patients were diagnosed with CAPF. Median serum pancreatic amylase (P-AMY) levels with CAPF on postoperative day (POD)1 and POD2 were significantly higher than those without CAPF (P = .019 and P = .027, respectively). In multivariable analysis, serum P-AMY levels on POD1 were an independent predictive factor for CAPF (odds ratio 1.83, 95% confidence interval 1.07-3.14, P = .008).

CONCLUSIONS

Complications associated with pancreatic fluid after PT is associated with high serum P-AMY in the early postoperative period. Serum pancreatic enzymes in the first few postoperative days after PT may be a significant predictive factor for CAPF.

First-day plasma amylase detects patients at risk of complications after simultaneous pancreas-kidney transplantation

BACKGROUND

Simultaneous pancreas-kidney transplantation (SPK) carries a high risk of major postoperative complications, but knowledge on early warning signs and surrogate markers for postoperative complications is scarce.

AIMS

Our aim was to analyze the complication-predictive value of different laboratory tests in pancreas transplantation.

MATERIALS & METHODS

All SPKs in Finland between January 2010 and February 2020 were retrospectively analyzed. Levels of first three-day plasma amylase, drain fluid amylase, C-reactive protein, C-peptide, plasma trypsinogen, and white blood cell count were assessed for their performance predicting cumulative postoperative complications (assessed using the Comprehensive Complication Index) within 90 days from transplantation by using ROC analyses.

RESULTS

Of the 164 SPK patients included, 39 suffered at least one complication requiring laparotomy. First-day plasma amylase had the best value in predicting complications based on its high AUC value and easy clinical applicability, with an optimum cutoff of six times the upper normal limit. Negative predictive values (NPVs) and positive predictive values of this cutoff were 0.81 and 0.71 for any relaparotomy, and 0.91 and 0.71 for the Comprehensive Complication Index >47.7 (which equals the morbidity of two relaparotomies), respectively.

CONCLUSION

In conclusion, first-day plasma amylase could be able to detect patients at risk of complications after SPK.

Long-term outcome of islet transplantation on insulin-dependent diabetes mellitus: An observational cohort study

AIMS/INTRODUCTION

To investigate the long-term efficacy and safety of islet transplantation (ITx) compared with multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII).

MATERIALS AND METHODS

Among 619 patients diagnosed as insulin-dependent diabetes mellitus or type 1 diabetes at Kyoto University, Kyoto, Japan, seven patients were selected as the ITx group and 26 age-matched patients with no endogenous insulin secretion were selected as the MDI/CSII group. Hemoglobin A1c, aspartate aminotransferase/alanine aminotransferase (AST/ALT) and creatinine were assessed retrospectively at 1, 2, 5 and 10 years for both groups; serum C-peptide immunoreactivity was assessed for the ITx group. Major clinical events were also assessed.

RESULTS

Hemoglobin A1c improvement in ITx was significant at 1 year (8.4% [7.8-9.9%] at baseline to 7.1% [6.3-7.4%] in ITx vs 8.2% [7.4-9.8%] at baseline to 8.1% [7.3-9.5%] in MDI/CSII, P < 0.01 between groups), and was maintained at 2 years (7.4% [6.3-8.2%] vs 8.4% [7.4-9.6%], P = 0.11). The increase of stimulated C-peptide immunoreactivity was significant at 1 year (0.57 ng/mL [0.26-0.99 ng/mL], P < 0.05 from baseline) and 2 years (0.43 ng/mL [0.19-0.67 ng/mL], P < 0.05), although it became insignificant thereafter. There was no significant difference in AST/ALT or creatinine at 10 years, although a transient AST/ALT elevation was observed in ITx. In regard to clinical events, the occurrence of severe hypoglycemia was 14% vs 31% (relative risk 0.46, P = 0.64), that of infectious disease was 43% vs 12% (relative risk 3.71, P = 0.09) and digestive symptoms was 43% vs 7.7% (relative risk 5.57, P = 0.05) in ITx vs MDI/CSII, respectively. No patient died in either group.

CONCLUSIONS

The present findings showed that ITx was considered to contribute to the reduction of hypoglycemia and better glycemic control with tolerable, but attention-requiring, risks over a period of 10 years compared with MDI/CSII.

Potential benefits of melatonin in organ transplantation: a review

Organ transplantation is a useful therapeutic tool for patients with end-stage organ failure; however, graft rejection is a major obstacle in terms of a successful treatment. Rejection is usually a consequence of a complex immunological and nonimmunological antigen-independent cascade of events, including free radical-mediated ischemia-reperfusion injury (IRI). To reduce the frequency of this outcome, continuing improvements in the efficacy of antirejection drugs are a top priority to enhance the long-term survival of transplant recipients. Melatonin (N-acetyl-5-methoxytryptamine) is a powerful antioxidant and ant-inflammatory agent synthesized from the essential amino acid l-tryptophan; it is produced by the pineal gland as well as by many other organs including ovary, testes, bone marrow, gut, placenta, and liver. Melatonin has proven to be a potentially useful therapeutic tool in the reduction of graft rejection. Its benefits are based on its direct actions as a free radical scavenger as well as its indirect antioxidative actions in the stimulation of the cellular antioxidant defense system. Moreover, it has significant anti-inflammatory activity. Melatonin has been found to improve the beneficial effects of preservation fluids when they are enriched with the indoleamine. This article reviews the experimental evidence that melatonin is useful in reducing graft failure, especially in cardiac, bone, otolaryngology, ovarian, testicular, lung, pancreas, kidney, and liver transplantation.

Systemic inflammation in xenograft recipients (SIXR): A new paradigm in pig-to-primate xenotransplantation?

Inflammation is a complex response that involves interactions between multiple proteins in the human body. The interaction between inflammation and coagulation is well-recognized, but its role in the dysregulation of coagulation in xenograft recipients is not well-understood. Additionally, inflammation is known to prevent the development of T cell tolerance after transplantation. Recent evidence indicates that systemic inflammation precedes and may be promoting activation of coagulation after pig-to-primate xenotransplantation. Activated recipient innate immune cells expressing tissue factor are increased after xenotransplantation, irrespective of immunosuppressive therapy. With immunosuppression, C-reactive protein (C-RP), fibrinogen, and interleukin-6 levels are significantly increased in pig artery patch recipients. In pig organ recipients, increased C-RP levels are observed prior to the development of features of consumptive coagulopathy. Systemic inflammation in xenograft recipients (Sixr) may be a key factor in the development of dysregulation of coagulation, as well as in resistance to immunosuppressive therapy. While genetic modification of the donor pigs provides protection against humoral responses and the development of thrombotic microangiopathy, therapeutic prevention of Sixr may be essential in order to prevent systemic dysregulation of coagulation in xenograft recipients without the use of intensive immunosuppression.

Hydrogen-rich saline protects against ischemia/reperfusion injury in grafts after pancreas transplantations by reducing oxidative stress in rats

Purpose. This study aimed to investigate the therapeutic potential of hydrogen-rich saline on pancreatic ischemia/reperfusion (I/R) injury in rats. Methods. Eighty heterotopic pancreas transplantations (HPT) were performed in syngenic rats. The receptors were randomized blindly into the following three groups: the HPT group and two groups that underwent transplantation and administration of hydrogen-rich saline (HS, >0.6 mM, 6 mL/kg) or normal saline (NS, 6 mL/kg) via the tail vein at the beginning of reperfusion (HPT + HS group, HPT + NS group). Samples from the pancreas and blood were taken at 12 hours after reperfusion. The protective effects of hydrogen-rich saline against I/R injury were evaluated by determining the changes in histopathology and measuring serological parameters, oxidative stress-associated molecules, and proinflammatory cytokines. Results. Administration of hydrogen-rich saline produced notable protection against pancreatic I/R injury in rats. Histopathological improvements and recovery of impaired pancreatic function were observed. In addition, TNF-α, IL-1β, and IL-6 were reduced markedly in the HPT + HS group. Additionally, there were noticeable inhibitory effects on the pancreatic malondialdehyde level and considerable recruitment of SOD and GPx, which are antioxidants. Conclusion. Hydrogen-rich saline treatment significantly attenuated the severity of pancreatic I/R injury in rats, possibly by reducing oxidative stress and inflammation.

Has the gap between pancreas and islet transplantation closed?

Both pancreas and islet transplantations are therapeutic options for complicated type 1 diabetes. Until recent years, outcomes of islet transplantation have been significantly inferior to those of whole pancreas. Islet transplantation is primarily performed alone in patients with severe hypoglycemia, and recent registry reports have suggested that results of islet transplantation alone in this indication may be about to match those of pancreas transplant alone in insulin independence. Figures of 50% insulin independence at 5 years for either procedure have been cited. In this article, we address the question whether islet transplantation has indeed bridged the gap with whole pancreas. Looking at the evidence to answer this question, we propose that although pancreas may still be more efficient in taking recipients off insulin than islets, there are in fact numerous "gaps" separating both procedures that must be taken into the equation. These "gaps" relate to organ utilization, organ allocation, indication for transplantation, and morbidity. In-depth analysis reveals that islet transplantation, in fact, has an edge on whole pancreas in some of these aspects. Accordingly, attempts should be made to bridge these gaps from both sides to achieve the same level of success with either procedure. More realistically, it is likely that some of these gaps will remain and that both procedures will coexist and complement each other, to ensure that β cell replacement can be successfully implemented in the greatest possible number of patients with type 1 diabetes.

Systemic inflammation in xenograft recipients precedes activation of coagulation

BACKGROUND

Dysregulation of coagulation is considered a major barrier against successful pig organ xenotransplantation in non-human primates. Inflammation is known to promote activation of coagulation. The role of pro-inflammatory factors as well as the relationship between inflammation and activation of coagulation in xenograft recipients is poorly understood.

METHODS

Baboons received kidney (n=3), heart (n=4), or artery patch (n=8) xenografts from α1,3-galactosyltransferase gene-knockout (GTKO) pigs or GTKO pigs additionally transgenic for human complement-regulatory protein CD46 (GTKO/CD46). Immunosuppression (IS) was based on either CTLA4Ig or anti-CD154 costimulation blockade. Three artery patch recipients did not receive IS. Pro-inflammatory cytokines, chemokines, and coagulation parameters were evaluated in the circulation after transplantation. In artery patch recipients, monocytes and dendritic cells (DC) were monitored in peripheral blood. Expression of tissue factor (TF) and CD40 on monocytes and DC were assessed by flow cytometry. C-reactive protein (C-RP) levels in the blood and C-RP deposition in xenografts as well as native organs were evaluated. Baboon and pig C-RP mRNA in heart and kidney xenografts were evaluated.

RESULTS

In heart and kidney xenograft recipients, the levels of INFγ, TNF-α, IL-12, and IL-8 were not significantly higher after transplantation. However, MCP-1 and IL-6 levels were significantly higher after transplantation, particularly in kidney recipients. Elevated C-RP levels preceded activation of coagulation in heart and kidney recipients, where high levels of C-RP were maintained until the time of euthanasia in both heart and kidney recipients. In artery patch recipients, INFγ, TNF-α, IL-12, IL-8, and MCP-1 were elevated with no IS, while IL-6 was not. With IS, INFγ, TNF-α, IL-12, IL-8, and MCP-1 were reduced, but IL-6 was elevated. Elevated IL-6 levels were observed as early as 2 weeks in artery patch recipients. While IS was associated with reduced thrombin activation, fibrinogen and C-RP levels were increased when IS was given. There was a significant positive correlation between C-RP, IL-6, and fibrinogen levels. Additionally, absolute numbers of monocytes were significantly increased when IS was given, but not without IS. This was associated with increased CD40 and TF expression on CD14+ monocytes and lineage(neg) CD11c+ DC, with increased differentiation of the pro-inflammatory CD14+ CD11c+ monocyte population. At the time of euthanasia, C-RP deposition in kidney and heart xenografts, C-RP positive cells in artery patch xenograft and native lungs were detected. Finally, high levels of both pig and baboon C-RP mRNA were detected in heart and kidney xenografts.

CONCLUSIONS

Inflammatory responses precede activation of coagulation after organ xenotransplantation. Early upregulation of C-RP and IL-6 levels may amplify activation of coagulation through upregulation of TF on innate immune cells. Prevention of systemic inflammation in xenograft recipients (SIXR) may be required to prevent dysregulation of coagulation and avoid excessive IS after xenotransplantation.

Evaluation of Institut Georges Lopez-1 preservation solution in pig pancreas transplantation: a pilot study

BACKGROUND

Institut Georges Lopez-1 preservation solution (IGL-1) is an emerging extracellular-type electrolyte solution, low in viscosity, containing polyethylene glycol 35 as a colloid. Although IGL-1 has shown beneficial outcomes in kidney and liver preservation, this pilot study is the first to evaluate the efficacy of IGL-1 in pancreas transplantation (PT) compared with the University of Wisconsin solution (UW).

METHODS

Sixteen Landrace pigs underwent allogeneic PT with 16 hr of cold ischemia. Grafts were preserved with IGL-1 (n=8) or UW (n=8). No immunosuppression was administered. We analyzed graft function, the acute-phase response, and oxidative stress in the pancreatic graft monitoring membrane fluidity and lipid peroxidation.

RESULTS

All eight grafts with IGL-1, but only six with UW, were functioning. Graft failures with UW resulted from graft thrombosis. There were no differences between the two solutions in the number of normoglycemic days (IGL-1: 11.5 ± 6.2 versus UW: 8.5 ± 4.4 days, P=0.1357), nor in lipid peroxidation during 16-hr cold ischemia (P=0.672), or reperfusion (P=0.185), but IGL-1 prevented changes in membrane fluidity after reperfusion when compared with UW (P=0.026).

CONCLUSION

IGL-1 offered the same degree of safety and effectiveness as UW in our model of pig PT with 16 hr of cold ischemia.

Melatonin prolongs graft survival of pancreas allotransplants in pigs

Oxidative stress is involved in ischemia-reperfusion injury and allograft rejection after transplantation. We studied two well-known antioxidants, melatonin and ascorbic acid (AA), in relation to the survival of a pancreas transplantation model without immunosuppression. Forty-eight Landrace pigs were divided into three groups (n = 16 each; eight donors and eight recipients) that received melatonin, AA, or no antioxidant therapy (controls). Melatonin and AA were administered (10 mg/kg body weight) intravenously to donors and recipients during surgery and on postoperative days 1-7. The molecules were also added (5 mm) to a University of Wisconsin preservation solution during organ cold storage. Melatonin significantly delayed acute rejection and prolonged allograft survival (25.1 ± 7.7 days) compared with the controls (8.1 ± 0.8 days, P = 0.013) and the AA group (9.4 ± 1.6 days, P = 0.049). Melatonin reduced indicators of oxidative stress, malondialdehyde, and 4-hydroxyalkenals, in pancreatic samples collected during procurement, cold ischemia, and reperfusion. Melatonin also reduced serum pig-major acute-phase protein/inter-α-trypsin inhibitor heavy chain 4 (pMAP/ITIH(4)) in the early post-transplantation period. AA only partially reduced oxidative damage 30 min postreperfusion and failed to prevent pMAP/ITIH(4) elevations. These findings suggested that melatonin may be a useful therapeutic tool for organ transplantation.

Increased serum levels of C-reactive protein precede anastomotic leakage in colorectal surgery

BACKGROUND

Anastomotic leakage (AL) is a severe complication following colorectal surgery. C-reactive protein (CRP) is considered to be an indicator of postoperative complications.

MATERIALS AND METHODS

Between August 2002 and August 2005 342 colorectal resections with primary anastomosis were performed at the Department of General and Vascular Surgery. Johann Wolfgang Goethe-University Frankfurt. For this retrospective study serum CRP was measured daily until postoperative day 7, and in cases of AL it was excluded from statistical analysis beginning with the day on which the AL was diagnosed.

RESULTS

Twenty-six of 342 (7.6%) patients developed AL at a mean of 8.7 days postoperatively. The in-hospital mortality was 3.5% for all patients and was significantly higher in the AL group (11.5 versus 2.8%). The CRP level in the two groups showed a peak on day 2.5 and day 2.2, respectively. In case of postoperative AL the CRP level did not show a marked decline during the next few days. Compared to the cases where AL did not develop, there was a significantly higher increase in CRP from the preoperative level to the levels measured on postoperative day 3, 5, 6 and 7. Higher CRP levels were observed in patients experiencing pneumonia or urinary tract infection, but the decrease of CRP values was not as slow as in cases of AL.

CONCLUSIONS

This study shows serum CRP level to be a relevant marker in detecting postoperative complications in colorectal surgery. Prolonged elevation and a missing decline in CRP level precede the occurrence of AL.

Influence of donor- and recipient-specific factors on the postoperative course after combined pancreas-kidney transplantation

INTRODUCTION

Simultaneous pancreas-kidney (SPK) transplantation is state-of-the-art therapy for patients with type-1 diabetes mellitus and end-stage renal failure. Improvement of long-term organ function and long-term survival after transplantation is the main focus of current research, but improvement of the early postoperative course is very important for the patient. Pancreas transplantation is associated with postoperative complications. We defined and identified donor- and recipient-specific factors related to postoperative complications.

PATIENTS AND METHODS

We carried out 210 SPKs from April 1995 to December 2007. The early postoperative course until first discharge from hospital was analyzed. Complications (pancreas-specific and surgical) were revisited. Donor-specific factors such as sex, age, body mass index (BMI), laboratory values, catecholamine administration, time in the intensive care unit, preprocurement blood substitution, and asystolic periods, as well as factors related to the organ donation procedure, were assessed. Recipient-specific factors such as age, sex, BMI, and blood group were correlated with the prevalence of complications and postoperative outcome. Donor-specific risk factors correlating with postoperative complications included donor age, BMI, and blood transfusion in the donor before organ donation.

RESULTS

Graft preservation with histidine-tryptophan-ketoglutarate perfusion solution was related to a significantly higher number of surgical complications.When analyzing recipient-specific factors, pre-existing cardiac diseases influenced the prevalence of postoperative complications. The duration of the transplantation procedure was associated with significantly more complications. The anastomosis time was not significantly related to an increased prevalence of complications. The choice of immunosuppression had a significant effect on pancreas-specific complications, demonstrating that antithymocyte globulin instead of daclizumab had a negative effect. Initial immunosuppression with tacrolimus combined with mycophenolate mofetil (MMF) caused significantly fewer pancreas-related complications in comparison with tacrolimus combined with rapamycin as well as compared with cyclosporine combined with MMF. A high level of C-reactive protein within the first 7 days after transplantation was significantly related to an increased prevalence of complications.

CONCLUSIONS

Early postoperative complications after combined pancreas-kidney transplantation have a considerable effect on short- and long-term outcomes. Several statistically relevant factors related to pancreas- or surgery-associated complications could be identified. These data may help to improve early outcome after SPK by consideration of relevant risk factors when choosing an organ and a recipient for transplantation.

Diagnostic accuracy of C-reactive protein for intraabdominal infections after colorectal resections

BACKGROUND

Intraabdominal infections are caused mainly by anastomotic leaks and represent a serious complication. Diagnosis is usually made when patients become critically ill. Though inflammatory markers, including C-reactive protein (CRP) and white blood count (WBC), may contribute to an early diagnosis, their clinical roles remain unclear. The diagnostic accuracy of continuous tests depends on the choice of cut-off values. We analyzed the diagnostic accuracy of serial CRP and WBC measurements to detect infectious complications after colorectal resections.

PATIENTS AND METHODS

The CRP and WBC were routinely measured postoperatively in 231 consecutive patients undergoing colorectal resection. Clinical outcome was registered with regard to postoperative complications. The diagnostic accuracy of CRP and WBC was analyzed by receiver operating characteristics (ROC) curve analysis with intra- and extraabdominal infectious complications as the outcome.

RESULTS

Increased CRP levels on postoperative day (POD) 3 were associated with intraabdominal infections. The best cut-off value was 190 (sensitivity, 0.82; specificity, 0.73). The area under the ROC curve was 0.82. On POD 5 and 7, the diagnostic accuracy of CRP was similar.

CONCLUSION

Serial CRP measurements are helpful for detecting intraabdominal infections after colorectal resection. Persistently elevated CRP values after POD 3 should be investigated for intraabdominal infection.

Octreotide attenuates impaired microcirculation in postischemic pancreatitis when administered before induction of ischemia

BACKGROUND

Ischemia-reperfusion injury of the pancreas causes impairment of microcirculation leading to pancreatitis. Postischemic pancreatitis is the most common reason for graft failure in pancreas transplantation. In animal models, octreotide has been described to have beneficial effects on acute pancreatitis by reducing pancreatic enzyme release and edema formation by preventing the increase of macromolecular extravasation. In contrast to earlier experimental setups, this study investigated the influence of octreotide on ischemia-reperfusion pancreatitis when administered before induction of ischemia.

METHODS

Sprague-Dawley rats were randomly assigned to three groups: (1) sham-operated animals (sham group, n=7); (2) 1 hr ischemia followed by 1 hr reperfusion (control group, n=7); (3) administration of 50 microg/kg octreotide intravenously 15 min before ischemia (octreotide group, n=7). At the end of reperfusion, intravital fluorescence microscopy was performed assessing the functional capillary density (FCD), leukocyte-endothelium interaction (LEI), and the microvascular permeability. Finally serum amylase and lipase were measured.

RESULTS

The application of octreotide significantly reduced the ischemia-reperfusion-induced reduction of FCD (318.4+/-44.1 cm/cm vs. 257.4+/-11.7 cm/cm, P<0.001). The increase of LEI due to ischemia-reperfusion (466.9+/-52.2 cells/mm) was reduced in the octreotide group (264.4+/-55.1, P=0.001). Permeability was significantly lower in the octreotide group (0.56+/-0.57x10 cm/sec vs. 2.2.1+/-0.54x10 cm/sec, P<0.001). The level of serum lipase was reduced significantly after octreotide therapy (72.4+/-53.4 U/L vs. 136.7+/-66.5 U/L, P=0.026).

CONCLUSION

Octreotide significantly attenuated pancreatic dysfunction caused by ischemia-reperfusion when given before ischemia. Furthermore, we could prove for the first time a beneficial role of octreotide on preservation of the microvascular barrier for macromolecules.

Pancreatic ischemia/reperfusion injury: impact of different preservation temperatures

OBJECTIVES

Pancreatic ischemia/reperfusion injury (IRI) can influence the results after transplantation. Temperature during ischemia can affect IRI. A temperature of 4 degrees C is assumed as optimal for graft preservation. There are no data about the impact of different ischemia temperatures in pancreatic IRI.

METHODS

Ischemia/reperfusion injury was induced in pancreatic tail segments (2-hour ischemia, 2-hour reperfusion), with rats (7/group) without ischemia served as control. Animals were randomized to the different experimental groups. To achieve the desired temperature (4, 18, or 37 degrees C and 37 degrees C control), pancreatic tail segments were superfused with temperated saline. After reperfusion, microcirculation was observed by intravital fluorescence microscopy. Functional capillary density (FCD), leukocyte adherence in post-capillary venules, and histological damage were analyzed.

RESULTS

In IRI groups, decrease of FCD 1 and 2 hours after reperfusion compared with baseline measurements was significant. Functional capillary density in 4 degrees C was better as compared with 18 and 37 degrees C after reperfusion. Lower adherent leukocytes were seen in 4 and 18 degrees C, compared with 37 degrees C and also to CO. In 4 degrees C, histological damage was lower as compared with 18 and 37 degrees C.

CONCLUSIONS

We could demonstrate that also in pancreatic IRI, tissue injury is temperature dependent. Compared with 37 degrees C, although a protective effect is established already at 18 degrees C, more protection is achieved with storage at 4 degrees C. Our data suggest that 4 degrees C has the best protective effect on pancreatic IRI.

High levels of donor CCL2/MCP-1 predict graft-related complications and poor graft survival after kidney-pancreas transplantation

In this study we analyzed the role of CCL2, a member of the chemokine family, in early graft damage. Using simultaneous kidney-pancreas transplantation (SPK) as a model, we showed that brain death significantly increases circulating CCL2 levels in humans. We found that in such situations, high donor CCL2 levels (measured before organ recovery and at the onset of cold preservation) correlate with increased postreperfusion release of CCL2 by both the graft and recipient throughout the week following transplantation (n = 28). In a retrospective study of 77 SPK recipients, we found a significant negative association between high donor levels of CCL2 and graft survival. Decreased survival in these patients is related to early posttransplant complications, including a higher incidence of pancreas thrombosis and delayed kidney function. Taken together our data indicate that high CCL2 levels in the donor serum predict both an increase in graft/recipient CCL2 production and poor graft survival. This suggests that the severity of the inflammatory response induced by brain death influences the posttransplant inflammatory response, independent of subsequent ischemia and reperfusion.

Protective role of heme oxygenase-1 in pancreatic microcirculatory dysfunction after ischemia/reperfusion in rats

OBJECTIVES

Microcirculatory derangements caused by ischemia and reperfusion (I/R) play a pivotal role in acute and graft pancreatitis. The inducible enzyme heme oxygenase 1 (HO-1) has been shown to decrease I/R injury by modulation of capillary perfusion in other organs. It was the aim of this study to evaluate the effect of HO-1 induction on pancreatic microcirculation after I/R.

METHODS

Rats were randomized into 4 groups: (1) sham controls; (2) 1-hour ischemia and 2-hour reperfusion (I/R); (3) I/R + cobalt protoporphyrin (CoPP), an HO-1 inducer; and (4) I/R + CoPP + tin protoporphyrin, an HO inhibitor. Functional capillary density (FCD) and leukocyte endothelium interaction were analyzed using intravital microscopy during reperfusion. Expression of HO-1 mRNA, HO-1 protein, and HO activity were assessed by Northern blot, Western blot, and an HO activity assay.

RESULTS

Functional capillary density decreased significantly in the I/R group as compared with sham controls. Cobalt protoporphyrin treatment increased FCD to control values. In contrast, HO inhibition in CoPP-pretreated animals lowered FCD and increased leukocyte endothelium interaction significantly. Cobalt protoporphyrin administration increased HO-1 mRNA, protein, and HO activity, whereas activity of the enzyme was reduced after injection of tin protoporphyrin.

CONCLUSIONS

Heme oxygenase 1 plays a beneficial role in pancreatic microcirculatory derangements after I/R. This could be of therapeutic relevance after pancreas transplantation and other forms of postischemic pancreatitis.

Induction of heme oxygenase-1 improves the survival of pancreas grafts by prevention of pancreatitis after transplantation

BACKGROUND

Ischemia/reperfusion (I/R) injury after pancreas transplantation might result in graft pancreatitis. The role of heme oxygenase-1 (HO-1) in pancreas transplantation and prevention of graft pancreatitis is unknown.

METHOD

We studied the impact of HO-1 induction with cobalt protoporphyrin (CoPP) in experimental pancreas transplantation with moderate (6 hr) and prolonged (20 hr) cold ischemic time (CIT). Donor animals received CoPP 5 mg/kg intraperitoneal at 48 hr or intraperitoneal saline injections in the corresponding control groups before procurement. Harvested grafts were perfused with HTK solution and stored at 4 degrees C.

RESULTS

After prolonged CIT, graft survival was 100% with CoPP pretreatment in contrast to only 37.5% without pretreatment. CoPP-pretreated grafts demonstrated an unimpaired endocrine graft function at moderate and prolonged CIT. Serum lipase activity as a sign of exocrine preservation was significantly lower. In addition, morphological architecture was well preserved. CoPP pretreatment markedly increased HO-1 gene expression in donor pancreas (130-fold increase) by means of quantitative reverse transcriptase -polymerase chain reaction. Immunohistochemical examinations showed that the increase of HO-1 on the protein level was related to HO-1-positive donor macrophages in the pancreas grafts. HO-1 overexpression was accompanied by significant decrease of proinflammatory cytokines such as tumor necrosis factor-alpha, interleukin (IL)-2, IL-6, interferon-y, and by significant increase of the anti-inflammatory cytokine IL-10 and less expression of adhesion molecules such as e- and p-selectins.

CONCLUSIONS

HO-1 is highly inducible in the allograft rat pancreas and associated with a survival benefit and good graft function after transplantation. This study contributes to the beneficial potentials of HO-1 for the prevention of graft pancreatitis.

Persisting elevation of C-reactive protein after pancreatic resections can indicate developing inflammatory complications

BACKGROUND

Serum C-reactive protein (CRP) is an established discriminating factor for necrotizing pancreatitis. In this study, the CRP response with respect to inflammatory postoperative complications was examined in a large, homogeneous series of pancreatic resections in order to define a relevant clinical parameter for early detection of inflammatory postoperative complications.

METHODS

688 consecutive pancreatic resections with jejunal anastomosis were screened for inflammatory postoperative complications based on a prospective database. Ninety-one patients had at least one inflammatory postoperative complication and were compared to a subgroup of 60 consecutive patients with uneventful postoperative courses.

RESULTS

In the postoperative setting after pancreatic resection, CRP peaked on postoperative day (POD) 3 with a median serum CRP of 132 mg/L, and gradually decreased thereafter in patients with an uncomplicated postoperative course. In complicated cases (with the exception of cholangitis), increase in CRP was significantly greater, peaked on POD 3 (median CRP 173 mg/L), and persisted thereafter, whereas white blood cell count and body temperature did not differ significantly from uneventful courses until POD 6. The median day of diagnosis of inflammatory postoperative complications was POD 9. A cutoff CRP value of 140 mg/dL on POD 4 yielded a positive predictive value of 89.1% (adjusted to the prevalence of inflammatory postoperative complications: 48.7%) with a specificity of 87.1% and a sensitivity of 69.5% for inflammatory postoperative complications.

CONCLUSION

Persistence of CRP elevation above 140 mg/dL on POD 4 is predictive of inflammatory postoperative complications and should prompt an intense clinical search for major septic processes (e.g. pancreatic fistula or abscess) if pneumonia and wound infection are unlikely or excluded.

C-reactive protein as early predictor for infectious postoperative complications in rectal surgery

BACKGROUND

This study evaluated the role of the acute phase C-reactive protein (CRP) in the postoperative course of a large series of rectal resections on the basis of a prospective database. Main focus of this study was the early identification of complications.

MATERIALS AND METHODS

Three hundred eighty-three rectal resections with primary anastomosis for rectal cancer were screened for infectious postoperative complications. Forty-eight complicated cases were identified and matched with 48 patients with an uneventful postoperative course.

RESULTS

In the postoperative setting, CRP peaked on postoperative day (POD) 2 with a median serum CRP of 140 mg/l and gradually declined thereafter in uncomplicated cases. In complicated cases, CRP elevation generally persisted after POD 2, whereas white blood cells and body temperature were within normal range in the early postoperative period. A cutoff CRP value of 140 mg/dl on PODs 3 and 4 resulted in predictive values of 85.7 and 90.5% (adjusted to the prevalence: 37.6 and 50.3%), sensitivities of 80.0 and 54.3%, and specificities of 81.0 and 92.3% for a complicated postoperative course (P<0.001), respectively.

CONCLUSION

Persistent CRP elevation and elevation of serum CRP above 140 mg/dl on PODs 3-4 are predictive of infectious postoperative complications and should prompt intense clinical search for an inflammatory process, especially for an anastomotic leak if pneumonia and wound infection are unlikely or excluded.

Remote preconditioning reduces microcirculatory disorders in pancreatic ischemia/reperfusion injury

OBJECTIVES

Remote preconditioning (RPC) can protect from ischemia/reperfusion injury (IRI). We investigated the influence of RPC in pancreatic IRI.

METHODS

Wistar rats were randomized to 2 hours of ischemia and 2 hours of reperfusion of a pancreatic tail segment with or without 15 minutes of infrarenal ischemia 60 minutes before IRI. Microcirculatory measurements before ischemia and 1 and 2 hours after reperfusion included functional capillary density and leukocyte adherence in postcapillary venules, quantified by intravital fluorescence microscopy. Histology and tissue myeloperoxidase activity were further parameters of pancreatic injury.

RESULTS

Remote preconditioning caused an improvement of microcirculation (functional capillary density: 1 hour after reperfusion, 460 +/- 13 vs 350 +/- 9 cm/cm2; 2 hours after reperfusion, 437 +/- 13 vs 295 +/- 13 cm/cm2; P < 0.01) and reduced inflammatory tissue response (leukocyte adherence in postcapillary venules: 2 hours after reperfusion, 155 +/- 55 vs 748 +/- 187 cells/mm2; P < 0.01). Histology was significantly better in preconditioned animals (IR, 8.1+/- 1.3 score points; RPC, 6.2 +/- 1.3 score points; P < 0.05). The difference in myeloperoxidase activity was not significant (ischemia/reperfusion [IR], 105 +/- 72; RPC, 245 +/- 209 mU x min(-1) x mg(ti)(-1); P = 0.13).

CONCLUSIONS

With our dynamic functional microcirculatory measurements, we could demonstrate that RPC is a feasible method to reduce experimental pancreatic IRI. This was seen in an attenuation of nutritive tissue perfusion and a reduction of inflammatory tissue response and a lower histological damage. Because it is easy to perform before organ harvest, RPC could be a step to improve organ procurement in pancreas transplantation. Clinical studies are the next step to evaluate RPC in pancreas transplantation.

Lipid peroxidation in ischemia-reperfusion oxidative injury of the graft preserved in Celsior and University of Wisconsin solutions on a pig pancreas transplantation model

BACKGROUND

Graft pancreatitis (GP) is one the main technical problems associated with pancreas transplant (PT). It occurs in 20% of patients representing a risk factor for thrombosis and cause of graft loss. GP is related to oxidative effects from oxygen-derived free radicals (OFR) in ischemia-reperfusion injury. We evaluated lipid peroxidation by the OFR in the PT of pig organs preserved with either Celsior or Wisconsin solutions.

METHODS

In Landrace pigs we performed 24 pancreas allografts, which were preserved 18 or 24 hours: 12 with Celsior solution (CS) and 12 with Wisconsin solution (UW). No immunosuppression was administered. The oxidative effects were determined by quantification of malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) and of the carbonyl groups of proteins in our pancreatic tissue samples and measured at different times: (A) baseline in the donor, (B) after perfusion of the graft, (C) after the ischemia period, and (D) 30 minutes after ischemia-reperfusion of the graft.

RESULTS

The MDA and 4-HDA values were similar in conditions A, B, and C, but showed an extraordinary increase after ischemia-reperfusion in D, among both the 18- or 24-hour preserved grafts and in the same proportion with CS and UW. The carbonyl groups of the proteins rose in conditions B and C (cold ischemia), but less so in state D (reperfusion).

CONCLUSIONS

The oxidative injury of a pancreatic graft preserved for 18 or 24 hours occurs during reperfusion, with an extraordinary intensity, but similarly with CS and UW, an observation that may help to explain graft pancreatitis.

Characterization of ischemia/reperfusion-induced gene expression in experimental pancreas transplantation

BACKGROUND

The aim of this study was to identify genes that are differentially expressed in the early period after pancreatic cold ischemia/reperfusion (I/R) injury.

METHODS

Grafts of isogeneic rat pancreaticoduodenal transplantation were subjected to different preservation solutions and cold ischemia times (CITs): University of Wisconsin (UW), 6-hour CIT; UW, 18-hour CIT; and physiologic saline solution, 6-hour CIT. Animals that did not receive transplants served as controls. At 2-hour reperfusion, grafts were removed and pancreatic RNA was isolated, pooled, and hybridized to Affymetrix RG-U34A arrays. Quantitative reverse-transcription polymerase chain reaction was used to confirm the results of microarray technology.

RESULTS

A total of 49 genes were consistently upregulated (more than threefold) in all three groups of transplant recipient animals. Prominent genes include transcription factors; cytoskeletal factors; heat-shock proteins (e.g. Hsp27, Hsp90); molecules involved in inflammation (e.g. PAPIII), immunology, signal transduction, and translation; and genes that have not been associated with I/R injury so far (e.g. Best5). Messenger RNA levels of some genes were exclusively downregulated in response to the different conditions applied to the pancreatic grafts: Cybb, Reg3a, Per2, BMAL1, MAP, and Isl2.

CONCLUSIONS

These results provide new insight in I/R-induced gene expression after experimental pancreas transplantation. The reported upregulation of heat shock proteins, Best5, and PAPIII may play a pathologic role in pancreatic cold I/R injury and could therefore provide a promising perspective for further investigations.

Intermittent capillary perfusion in rat pancreas grafts following short- and long-term preservation in University of Wisconsin solution

In pancreas transplantation (PTx), ischemia/reperfusion-induced deterioration of graft-microcirculation is accompanied by alterations of intermittent capillary perfusion (IP; alternating cessation and resumption of capillary blood flow) is known to counteract malperfusion. Incidence and effectiveness of IP following short- versus long-term preservation of pancreas grafts with University of Wisconsin (UW) solution has not been examined so far. PTx was performed in Lewis rats following 2-h or 18-h preservation in UW solution. Using intravital fluorescence microscopy, functional capillary density (FCD), red blood cell (RBC) velocity, IP-incidence and -frequency were analyzed. Laser Doppler flowmetry allowed for the determination of erythrocyte flux and velocity. Measurements were performed at 30, 60 and 120 min after reperfusion. Nontransplanted animals served as controls. FCD, RBC-velocity and -flux remained unchanged in the 2-h group. IP was encountered in 87% of all observation areas at 120 min. After 18-h ischemia, FCD was significantly reduced, which was paralleled by a 50% incidence of IP at 120 min. Tissue edema and leukocyte infiltration in pancreas grafts following 18-h preservation were significantly enhanced. Therefore, IP is an important mechanism aimed at improving microcirculation and UW solution is suitable to preserve vasomotion-activities enabling long-term preservation in a pancreas graft.

Reduction of ischemia/reperfusion injury by antithrombin III after experimental pancreas transplantation

BACKGROUND

Graft pancreatitis is a major complication after pancreas transplantation. Antithrombin III (AT III) is an anticoagulatory and anti-inflammatory substance. The aim of our study was to evaluate a prophylactic application of AT III in experimental pancreas transplantation.

METHODS

Pancreas transplantation was performed in rats. Cold ischemia time (University of Wisconsin solution at 4 degrees C) was 12 hours. After 4 hours of reperfusion, pancreatic enzymes were assessed and the pancreas was evaluated by intravital microscopy and histologic and immunohistochemical examination. Recipients were allocated randomly to 2 groups: 1 control group (n = 6) and 1 group in which recipients received 125 IU AT III/kg 30 minutes before reperfusion (n = 6). Six animals that did not undergo transplantation served as healthy controls.

RESULTS

Enzyme levels showed no differences between the 2 transplantation groups but were significantly (P <.05) higher than in the control group. Histologic damage was significantly less evident in animals that received AT III compared with transplantation animals that did not receive AT III. During intravital microscopy, animals receiving AT III showed significantly higher capillary and venular erythrocyte velocities compared with untreated transplantation animals. The leukocyte-endothelium interaction in postcapillary venules was decreased significantly in animals with AT III treatment.

CONCLUSIONS

AT III pretreatment decreases tissue damage by attenuating microcirculatory disturbances and leukocyte adherence in experimental graft pancreatitis by its anti-inflammatory and anticoagulatory properties.