Immunogenicity of SARS-CoV-2 Vaccine in Kidney Transplant Recipients:A Cross-Sectional Study in Korea

Eighty-five Korean kidney transplant recipients who received three doses of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine were tested with anti-receptor binding domain (RBD) antibody and neutralizing antibody. High anti-RBD antibody (≥ 100 U/mL) and neutralizing antibody responses (≥ 30%) were detected in 51/85 (60.0%) patients.When we divided the patients with the time from transplantation to vaccination (< 1, 1–2.4, 2.5–4.9, and ≥ 5-year), anti-RBD antibody titers were 3.2 U/mL, 27.8 U/mL, 370.2 U/mL, and 5,094.2 U/mL (P < 0.001) and anti-neutralizing antibody levels were 2.2%, 11.6%, 45.6%, and 93.0% (P < 0.001), respectively. Multivariate analysis revealed increased antibody responses when the time from transplantation to vaccination was five years or longer (odds ratio, 12.0; confidence interval, 2.7–52.8). Korean kidney transplant recipients had suboptimal antibody responses after the third dose of SARS-CoV-2 vaccine. A shorter time from transplantation to vaccination was a risk factor for a low antibody response.

Expression of E-cadherin in pig kidney

E-cadherin is a cell adhesion molecule that plays an important role in maintaining renal epithelial polarity and integrity. The purpose of this study was to determine the exact cellular localization of E-cadherin in pig kidney. Kidney tissues from pigs were processed for light and electron microscopy immunocytochemistry, and immunoblot analysis. E-cadhedrin bands of the same size were detected by immunoblot of samples from rat and pig kidneys. In pig kidney, strong E-cadherin expression was observed in the basolateral plasma membrane of the tubular epithelial cells. E-cadherin immunolabeling was not detected in glomeruli or blood vessels of pig kidney. Double-labeling results demonstrated that E-cadherin was expressed in the calbindin D28k-positive distal convoluted tubule and H(+)-ATPase-positive collecting duct, but not in the aquaporin 1-positive, N-cadherin-positive proximal tubule. In contrast to rat, E-cadherin immunoreactivity was not expressed at detectable levels in the Tamm-Horsfall protein-positive thick ascending limb of pig kidney. Immunoelectron microscopy confirmed that E-cadherin was localized in both the lateral membranes and basal infoldings of the collecting duct. These results suggest that E-cadherin may be a critical adhesion molecule in the distal convoluted tubule and collecting duct cells of pig kidney.

Portal Vein Thrombosis / 대한혈관외과학회지

Portal vein thrombosis (PVT) is a clinical situation that usually begins at the extrahepatic portal vein and sometimes extends into the intrahepatic portal vein, or distally to the superior mesenteric and splenic veins. The clinical presentation (asymptomatic to fatal bowel ischemia) and etiology (liver cirrhosis, systemic cause such as hypercoagulable state and myeloproliferative diseases, local cause such as acute appendicitis) is so diverse that the clinical decision making is sometimes very difficult. When the thrombus extends into the superior mesenteric vein, bowel ischemia and infarction should be anticipated and prevented cautiously with immediate initiation of anticoagulant therapy. The most troublesome chronic sequelae of the portal vein thrombosis is portal vein hypertension, which deteriorates patients' quality of life. The goal of treatment is to prevent ischemic bowel infarction and portal vein hypertension. Color Doppler sonography, computed tomography, and magnetic resonance imaging are convenient diagnostic tools to confirm PVT. The systemic thrombotic state or cause of infection must be determined through serologic studies. It is helpful to divide PVT patients into cirrhotic and non-cirrhotic, acute and chronic patients. In cases of non-cirrhotic acute PVT, rapid correction of the systemic and local cause of thrombosis and early initiation of anticoagulant therapy are considered the gold standard of treatment. In cases of cirrhotic and chronic PVT, the risk of bleeding and the efficiency of anticoagulation therapy should be measured and balanced for each patient. This article discusses the debated issue of the various treatment paradigms for PVT.

Continuous Monitoring of Donor Specific Anti-HLA Antibody in Kidney Transplantation Patients / 대한이식학회지

BACKGROUND: A positive reaction at flow cytometry crossmatch (FCXM) has been highlighted by its predictive value for clinical outcome in kidney transplantation after accumulation of large clinical data. The detection of de novo development of anti-HLA antibodies after transplantation is associated with increased rejection and decreased graft survival. In this study, we report the experience for the detection of anti-donor specific antibody (DSA) by more sensitive FCXM methods in renal transplantation patients. METHODS: T and B cell FCXMs were performed on 11 pretransplant and 51 posttransplant sera from 11 patients who received renal grafts between 2004 and 2005. The posttransplant sera were collected in specific and regular intervals from posttranspant 1 week to 1 year. RESULTS: Among 62 sera, four (7.8%) from 2 patients showed positive FCXM. In one patient, pretransplant serum which was negative at previous CDCXM, and 2 consecutive sera collected at 1 week and 1 month after transplantation were positive at FCXM. And the antibody identified was B51 which was specific for one of donor alleles (DSA). In another patient, FCXM became positive 1 week after transplantation although pretransplant serum had negative results at both CDCXM and FCXM. Both patients had experienced more than one rejection episodes. CONCLUSIONS: Detection of DSA with more sensitive technique such as flow cytometry based method clearly displayed a beneficial effect for prediction of clinical outcome as a part of pretransplant compatibility test, and also as a posttransplant monitoring test to identify the de novo production of clinically significant DSA.

Differences in Bacterial Translocation Across the Large andSmall Bowel Walls after Ischemia and Reperfusion Injury

PURPOSE: Bacterial translocation is a major problem after ischemic bowel injuries such as mesenteric vessel obstruction or bowel strangulation. In this study, we investigated the differential character of bacterial translocation from the large and small bowel using Escherichia coli labeled with technetium 99m (99mTc-E.coli). METHOD: Male Sprague-Dawley rats weighing 200~300 g underwent laparotomy. The superior mesenteric artery and marginal arteries of the proximal jejunum and distal colon were occluded for 30 minutes and then re-perfused for 4 hours. A suspension containing 99mTc-E.coli was injected into the lumen of the proximal colon (group 1) and distal ileum (group 2). In the sham operation group (groups 3, 4), 99mTc-E.coli was also injected in the same manner without induction of ischemia and reperfusion injury. Two hours after E. coli injection, blood, mesenteric lymph nodes (MLN), liver, spleen, and lung were collected for quantitative analysis of radioactivity. Large and small bowel specimens were also harvested for microscopic examination. Student's t-test was used for statistical analysis. P< or =0.05 was considered statistically significant. RESULT: Compared with group 1, group 2 showed a significant increase in 99mTc-E.coli translocation from the lumen to all organs investigated, except with regard to MLN. The sham operation group (groups 3, 4) showed scanty bacterial translocation. The mucosal epithelial cell layers of both groups (groups 1, 2) were comparatively intact. CONCLUSION: The 99mTc-E.coli method was found to be suitable for studies of bacterial translocation from the small and large bowels. Bacterial translocation is much more likely to occur across the small bowel wall than across the large bowel wall.

A Pig to Canine Auxiliary Hepatic Xenotransplantation Model: Prevention of Hyperacute Rejection via Blocking the Kupffer Cells and Regulating the Complement Family

PURPOSE: We designed a pig to canine liver xenotransplantation model to study the diverse immunologic and hemodynamic consequences that follow xenotransplantation and hyperacute rejection. METHODS: The animals were divided into two groups: the cobra venom factor and Gadolinium chloride treatment group (CVF+Gd group) (3 cases) and the control group (3 cases). The donor pig's whole liver was harvested, and then the harvested pig's whole liver was transplanted into a dog after the dog underwent left hepatectomy. After reperfusion of the graft, blood samples were taken 20, 40 and 60 minutes after reperfusion, and the liver, lung and kidney tissues were taken 1 hour after reperfusion. RESULTS: In the control group, the grafts showed a patchy hypoperfused liver surface and it felt rubbery solid compared to the CVF+Gd group. The serum total protein, albumin, fibrinogen and platelets decreased abruptly and there were no significant differences between the two groups. The serum PT, PTT and FDP were increased in both groups and the CVF+Gd group showed a more obtuse slope than the control group. We could not find any intravascular pathologic changes on the microscopic findings of the graft. Only scant intravascular fibrin deposition was found. Hepatocellular vacuolization and sinusoidal dilatation were also found. There were patches of necrosis without any zonal distribution, intrasinusoidal neutrophil sequestration and interstitial hemorrhage. These findings were milder in the CVF+Gd group. CONCLUSION: The pig to canine partial auxiliary liver xenotransplantation model is feasible and it is a good model before starting to perform pig to primate liver xenotransplantation. In the CVF+Gd group, pathologic findings like patch hepatocyte necrosis etc. were less severe. As there were no corresponding vascular pathologic findings, these findings are not the direct effect of CVF and gadolinium treatment, and so other factors like Ischemia- reperfusion injury should be considered.

The Usefulness of Endotoxin for Detection of Mucosal Injury in Intestinal Obstruction

PURPOSE: The treatment outcome of an intestinal obstruction depends on the early recognition and emergent operation of a strangulated intestinal obstruction. Endotoxin is a lipopolysaccharide component of the cell wall of gram negative bacteria that normally exist in the intestinal lumen. When a strangulated obstruction occurs, the endotoxin passes transluminally into the peritoneal cavity and blood stream. A disruption of the mucosal barrier is an important putative cause in this pathogenesis. This study investigated the relationship between the endotoxin level and progress of an intestinal obstruction to a strangulated obstruction. METHODS: 25 adult male Sprague-Dawley rats (200~250 g) were divided into 3 groups, the control group, simple obstruction group, and closed loop obstruction group. An intestinal obstruction was induced using a silk tie. Blood samples and obstructed bowel wall specimens were obtained at 24, 48 and 72 hours after surgery. The endotoxin and IL-6 levels were examined, and all specimens were reviewed by a pathologist for mucosal damage after H-E staining. RESULTS: In the obstruction groups, dilated bowel loops at the proximal end of the obstruction site was identified but there were no ischemic changes. The endotoxin and IL-6 levels were similar regardless of the obstruction types and times. There were no differences between the three groups in the degree of mucosal damage. However, according to the endotoxin level, the groups with an endotoxin level < 0.2 EU/ml showed mild mucosal damage. The severity of mucosal damage increased with increasing endotoxin level. CONCLUSION: There is a positive relationship (r(2)=0.673, P-value=0.002) between the endotoxin level and mucosal damage. This suggests the possibility of using endotoxin as a predictive factor for the detection of mucosal injury in an intestinal obstruction. However, a larger scale will be needed to confirm the statistical significance.

Effect of Pre-reperfusion Intravascular Rinsing in a Canine Acute Limb Ischemia Model

PURPOSE: Reperfusion after acute ischemia is associated with high rates of morbidity and mortality due to the ischemic injury itself and the following myonephropathic metabolic syndrome, in spite of complete revascularization. Therefore, we attempted to verify the difference in reperfusion injury with or without pre-reperfusion intravascular rinsing in a canine acute limb ischemia model. METHOD: We used five female mongrel dogs. Complete acute hind limb ischemia was induced by infrarenal aortic and bilateral femoral artery clamping for 8 hours. We divided the dogs into two groups. In the rinse group (RG): three dogs were declamped with intravascular rinsing, and in the non-rinse group (non-RG): two dogs were declamped without any additional procedures. The perfusate solution was infused through both femoral arteries and was drained via both femoral veins. Serial blood samples were obtained four times. The gastrocnemius muscles were biopsied 3 days after reperfusion. RESULT: The results at preischemia, just before, 30 min, and 3 days after reperfusion were as follows: Creatine phosphokinase (CK) was 204, 1031, 1373, and 443 (IU/L) in the RG and 159, 3855, 6345, and 5455 (IU/L) in the non-RG. Lactate dehydrogenase (LDH) was 177, 248, 173, and 232 (IU/L) in the RG and 95, 508, 638, and 878 (IU/L) in the non-RG. Aspartate transaminase (AST) was 23, 50, 43, and 42 (IU/L) in the RG and 19, 118, 154, and 399 (IU/L) in the non-RG. Potassium (K) was 5.7, 5.8, 5.4, and 4.0 (mEq/L) in the RG and 5.4, 5.5, 5.7, and 5.3 (mEq/L) in the non-RG. Muscle injury in the non-RG was more severe than in the RG. CONCLUSION: There was a considerable difference between the groups in the CK, LDH and AST levels and the muscle biopsy findings. The results showed that the intravascular rinsing provided beneficial effects in reperfusion injury acute limb ischemia.

Ethyl Pyruvate Ameliorates Renal Ischemia- reperfusion Injury

PURPOSE: Reactive oxygen species (ROS) significantly contribute to ischemia-reperfusion injury, and are also associated with the gradual loss of renal function and renal failure following renal transplantation. Pyruvate is an endogenous antioxidant, but its use as a therapeutic agent for treating conditions mediated by oxidative stress is limited due to its poor stability in solution. However, ethyl pyruvate (EP), a soluble pyruvate derivative, has far greater stability than pyruvate; thus, may serve as a practical pyruvate precursor. Therefore, the ability of EP in the prevention of renal ischemia-reperfusion injury was assessed. METHODS: Sprague-Dawley rats (n=54) were subjected to 40 minutes of renal warm ischemia. The animals were divided into three groups: the sham group without warm ischemia (n=18), the EP group (n=18, EP given before ischemia), and the ischemic control (n=18). The serum levels of creatinine and TNF-alpha were measured 1, 3 and 5 days after induction of ischemia. The expression of high mobility group box-1 (HMGB-1), a delayed inflammatory mediator, was also assessed by Western blot of renal specimens. RESULTS: In the EP group, late improvements in the serum levels of creatinine and TNF-alpha were observed in comparison with the ischemic control. Based on this delayed effect, the expression of HMGB-1 was assessed in renal tissue. The HMGB-1 expression increased over time during the ischemia process, but EP suppressed this expression 3 and 5 days after renal ischemia-reperfusion injury. CONCLUSION: These results have demonstrated, for the first time, that EP ameliorates renal ischemia-reperfusion injury. EP attenuates the renal ischemia-reperfusion injury, at least in part, by suppressing the expression of HMGB-1, a late mediator of delayed inflammation.

The Role of HMGB1 and the Effect of Ethyl Pyruvate on Ischemia and Reperfusion Injury of Rat Kidney / 대한이식학회지

PURPOSE: High mobility group box-1 (HMGB1) was identified as a DNA binding protein that functions as a co-factor for proper transcriptional regulation in somatic cells. Extra- cellular HMGB1 acts as a potent pro-inflammatory cytokine that contributes to the pathogenesis of diverse inflammatory and infectious disorders. Ethyl pyruvate (EP), a stable aliphatic ester derived from pyruvic acid is the first described pharmacological inhibitor for HMGB1 secretion. We designed this study to identify the change of HMGB1 expression in rat kidney tissues of ischemia reperfusion injury and the effect of EP on the expression of HMGB1. METHODS: Sprague-Dawley rats (200~300 g) were subjected to 40 minutes of renal warm ischemia. The animals were divided into three groups: sham group without warm ischemia, the EP group (EP given before ischemia), and the ischemic control group. Kidneys were harvested and serum creatinine, IL-1 and IL-6 were measured at 6hours, 1 day, 3 days and 5 days after reperfusion. Immunohistochemical stain of HMGB-1 was done. RESULTS: Serum creatinine and IL-1 level were elevated in ischemic control group and EP injection group. In EP injection group, serum creatinine and IL-1 level were lower than the ischemic control group. In the rat 40minutes ischemia reperfusion model, HMGB1 expression was increased at 6 hours after reperfusion. which was decreased gradually at 1 day, 3 days, and 5 days after reperfusion. HMGB1 expression was more distinct at outer medullary area. intraperitoneal EP injection has no effect on the expression of HMGB1. CONCLUSION: From these results, we deduced a conclusion that the preventive effect of EP on the rat kidney ischemia reperfusion injury is not by the decreased expression of HMGB1 but by the prevention of the release of the HMGB1.

Nitric Oxide Synthesis in the Adult and Developing Kidney

Nitric oxide (NO) is synthesized within the adult and developing kidney and plays a critical role in the regulation of renal hemodynamics and tubule function. In the adult kidney, the regulation of NO synthesis is very cell type specific and subject to distinct control mechanisms of NO synthase (NOS) isoforms. Endothelial NOS (eNOS) is expressed in the endothelial cells of glomeruli, peritubular capillaries, and vascular bundles. Neuronal NOS (nNOS) is expressed in the tubular epithelial cells of the macula densa and inner medullary collecting duct. Furthermore, in the immature kidney, the expression of eNOS and nNOS shows unique patterns distinct from that is observed in the adult. This review will summarize the localization and presumable function of NOS isoforms in the adult and developing kidney.

The Effect of alpha-Melanocyte Stimulating Hormone on Renal Ischemia Reperfusion Injury / 대한이식학회지

PURPOSE: In ischemia-reperfusion induced renal injuries, cytokines, chemoattractant chemokines, adhesion molecules and nitric oxide play an important role. alpha-Melanocyte stimulating hormone (alpha-MSH) is a potent anti-inflammatory cytokine so the therapeutic effect of alpha-MSH on an ischemia-reperfusion induced acute renal failure is to be evaluated. METHODS: 40 male Spraque-Dawley rats were prepared for the experiment, they were classified into three classes (Sham, ischemic control and alpha-MSH injection). Both renal pedicles were clamped for 45 minutes. alpha-MSH (50 microgram) was injected intravenously three times, immediately before ischemia and reperfusion and 18 hour after reperfusion. Serum creatinine and histologic changes were analyzed between groups (Sham (n=6), ischemic control group (n=15), and alpha-MSH group (n=19)). RESULTS: Serum creatinine level decreased significantly at 24 hours after reperfusion in alpha-MSH treated animals (SCr24 0.78+/-0.23 mg/dL, 4.21+/-1.14 mg/dL, 3.01+/-1.19 mg/dL, repectively (P=0.008)), especially serum creatinine level at 48 hours after reperfusion much more dicreased in alpha-MSH group (SCr48 0.67+/-0.16 mg/dL, 4.21+/-2.03 mg/dL, 1.15+/-1.11 mg/dL, repectively (P=0.004)). Tubular neccrosis and neutrophil infiltration decreased signigicantly in alpha-MSH treated group (P=0.001). Mortality was noted 33.3% only at ischemic conrol group. CONCLUSION: we demonstrate the fact that alpha-MSH has protective role on ischemic renal injury and improves survival rates.

The Effect of Nitric Oxide Donor on the Endogenous Endothelin-1 Expression in Renal Ischemia-Reperfusion Injury

PURPOSE: The balance between nitric oxide (NO) and endothelin-1 (ET-1) production is essential to vascular function in controlling organ perfusion, and an elevated ET-1 in the peritubular capillary network, following renal transplantation, can be associated with renal allograft rejection. The administration of a nitric oxide donor during the preischemic period has been shown to protect the kidneys against an ischemia-reperfusion injury, but the mechanism underlying this therapeutic benefit remains to be completely understood. Our hypothesis is that the early administration of the NO donor, sodium nitroprusside (SNP), may suppress ET-1, and thereby improve the renal function in an ischemia-reperfusion injury. METHODS: Sprague Dawley rats were subjected to 60 minutes of renal warm ischemia, followed by a contralateral nephrectomy. Renal biopsies were performed prior to ischemia and reperfusion, and at 1 and 48 hours after the reperfusion. The animals were divided into 4 groups: a sham group, without warm ischemia, an early SNP group (SNP given before ischemia), a late SNP group (SNP given before reperfusion) and an ischemic control group. The ET-1 expression was assessed by a semiquantitative analysis by immunohistochemical staining with the ET-1 monoclonal antibody and Hematoxylin-Eosin stain. The serum creatinine was measured at 48 hours after the reperfusion. RESULTS: There were significant improvements in all parameters of the early SNP group compared with those in the late SNP and ischemic control groups, but there was no difference between the late SNP and ischemic control groups. CONCLUSION: These data suggest that the early administration of SNP in renal ischemia-reperfusion improves the renal function by suppressing the expression of ET-1.

Blockade of TGF-beta by Catheter-based Gene Transfer of a Soluble TGF-beta Type II Receptor Inhibits Neointima Formed after Stenting

BACKGROUND: Enhanced extracellular matrix (ECM) accumulation is an important finding in coronary stent restenotic tissue, in which TGF-beta, implicated in ECM formation, is expressed abundantly. We assessed the hypothesis that blockade of TGF-beta by the local delivery of an adenovirus expressing a soluble form of the TGF-beta type II receptor (AdT beta-ExR), inhibits stent-induced neointima in porcine coronary arteries. METHODS: Two remote coronary arterial segments (n=20) per pig randomly received 1x10(9) pfu of either AdT beta-ExR or adenovirus expressing beta-galactosidase (AdLacZ)/PBS, using an Infiltrator(TM). Stents (n=20) were deployed, after gene transfer, in each segment of 10 pigs. Localized transgene expression was confirmed by both reverse transcription-PCR and immunohistochemistry. Computer-based morphometric assessment was performed in the stented arteries 4 weeks after the gene transfer. RESULTS: There was significantly less intimal area (1.57+/-0.49 vs. 2.13+/-0.34 mm2), area ratio of intima/media (0.84+/-0.44 vs. 1.32+/-0.48) and higher neointimal cell density (3121+/-330 vs. 2812+/-183 cells/mm2) in the arteries treated with AdT beta-ExR compared to the controls (all, p<0.05). Neither the cell proliferation rate, assessed by PCNA immunohistochemistry, nor the injury score were significantly different between the two groups. The distribution of hyaluronan in the intima was less in 4 of the 6 AdT beta-ExR treated arteries compared to the controls. CONCLUSION: Blockade of TGF-beta, by a local in vivo gene transfer of a soluble TGF-beta receptor, inhibits stent-induced neointima, probably by inhibiting the ECM accumulation in porcine coronary arteries, which may have therapeutic potential in the inhibition of restenosis after stenting.

Efficacy and Safety of Rotating Pigtail Catheter: Lower Extremity Deep Vein Thrombosis of May-Thurner Syndrome

PURPOSE: The purpose of this study was to evaluate the efficacy and safety of mechanical fragmentation of iliofemoral deep vein thromboses (DVT) with rotating pigtail catheter followed by aspiration thrombectomy. METHOD: Thirteen patients (nine females, four males, 59.9+/-21.37 years old) with iliofemoral DVT underwent treatment for thirteen affected limbs. About 5~10 min after infusing 400,000~700,000 IU urokinase into the thrombosed deep veins, thromboses were fragmented by the mechanical action of the rotating pigtail catheter tip. After fragmentation of the thromboses, we aspirated the fragmented thromboses. Stent insertion or balloon angioplasty was applied if iliac vein stenosis was demonstrated after the above procedure was completed. We evaluated the total procedure time, volume of thrombolytic agent (urokinase), valvular injury, symptom-free time interval and success rate (primary patency rate). RESULT: In all 13 patients, iliofemoral DVT was successfully fragmented and aspirated using a combination method of rotating pigtail catheter and aspiration thrombectomy (clinical and technical success rate, 100%). The thromboses were declotted by rotating pigtail catheter in an average time of 5.7 minutes. Average duration of the total intervention was 108 min. Mean primary patency was about 4 months and there was no recurrence. Total UK average dose was 890,000 IU. There was no major complication such as pulmonary embolism or cerebral hemorrhage while the thrombus-fragmentation procedure was performed using rotating pigtail catheter. CONCLUSION: The combination method of rotating pigtail catheter and aspiration thrombectomy for treatment of iliofemoral DVT achieved rapid, safe, and effective recanalization in all cases without complication. Therefore, this procedure is a potential option in patients presenting with iliofemoral vein thrombosis.

Effects of Carvedilol on PDGF-induced Collagen Synthesis and Signal Transduction in Rat Vascular Smooth Muscle Cell / 대한이식학회지

PURPOSE: Proliferation, migration, and the accumulation of extracellular matrix (ECM) protein of vascular smooth muscle cells (VSMC) play roles for transplant arteriosclerosis. We have previously reported that carvedilol (CA) inhibits the proliferation and the migration of VSMCs. The present study examined the effects of CA on platelet-derived growth factor (PDGF)-induced collagen synthesis in VSMC and the roles of reactive oxygen species (ROS), extracellular signal- regulated protein kinase (ERK), and p38 mitogen-activated protein kinase (p38 MAPK). METHODS: Primary cultured rat VSMCs were obtained from aorta of Sprague-Dawley rats. Growth arrested and synchronized cells were pretreated with CA (10 nM~10micrometer) at 1 hour before the addition of PDGF 10 ng/ml. Collagen synthesis was measured by 3[H]-proline incorporation, ROS by flow cytometry using ROS-sensitivedichlorofluorescein (DCF) dye, and the activation of ERK andp38 MAPK by Western blot analysis. RESULTS: PDGF significantly increased collagen synthesis by 2.0-fold, intracellular ROS by 1.6-fold, the activation of ERK 1/2 and p38 MAPK by 4.2-fold and 3.9-fold compared to control, respectively. CA above 1micrometer inhibited PDGF-induced collagen synthesis. CA also inhibited DCF-sensitive ROS and the activation of ERK and p38 MAPK. All pharmacological inhibitors of ROS, ERK, and p38 MAPK effectively inhibited PDGF-induced collagen synthesis. CONCLUSION: These data suggest that CA inhibit PDGF-induced collagen synthesis possibly through inhibiting intracellular ROS and ERK 1/2 and p38 MAPK activation.

Pathologic Scoring and Postoperative Liver Function in Canine Partial Liver Transplantation: after Desferrioxamine Exposure / 대한이식학회지

PURPOSE: Liver biopsy plays an important role in the histopathological evaluation of the transplanted liver, but till now pretransplant graft biopsy has limited role in predicting primary non function of the graft. Desferrioxamine (DFO), the iron chelating agent, has been known to be effective in reducing rat liver ischemia-reperfusion injury. We tried desferrioxamine in canine partial liver transplantation, and pathologic scores were compared. METHODS: ~70% partial liver was harvested and reimplanted in same mongrel dog weighing about 25 kg. Desferrioxamine (20 mg/kg) was infused via splenic vein just from the beginning of reperfusion of the partial liver graft (n=5). Serum aspartate aminotransferase (AST) Alkaline phosphatase (ALP), Lactate dehydrogenase (LDH) were checked and compared with the control group (n=5). Morphological liver injury score were compared to the control group. Statistical analysis was done with independent T-test. RESULTS: Total ischemic time was 4 hours and 42 minutes in average. AST level was significantly lower in Desferrioxamine group at 1 hour and 48 hours after reperfusion, (P=0.4) ALP level was significantly lower in desferrioxamine group at 48 hours after reperfusion (P=0.4). LDH level in desferrioxamine group was lower than that of control group but without statistical significance. The pathologic score at 1 hour after reperfusion showed a reduced degree of sinusoidal injury among the DFO group but the difference was not statistically significant. The pathologic score just before harvest of the graft showed no correlation with serum AST, ALP, LDH levels at that time or at 1 hour or 48 hours after reperfusion. Only the pathologic score at 1 hour after reperfusion had significant correlation with the serum LDH levels at 48 hours after reperfusion. CONCLUSION: In canine live donor partial liver transplantation, desferrioxamine infusion just before reperfusion might be an effective way of reducing ischemia-reperfusion injury. And the pathologic grading on samples obtained at 1 hour after reperfusion showed a significant correlation with subsequent liver function

Ischemia-reperfusion Injury after Canine Liver Allo-transplantation: The Effect of Gadolinium Chloride

PURPOSE: The effective suppression of Kupffer cell function is believed to contribute to the prevention of preservation/ reperfusion injury. In this study, the effect of Gadolinium, a synthetic Kupffer cell suppressor, on the reperfusion injury was examined using a canine partial liver transplant model. METHODS: About 70% of the liver was harvested and reimplanted in a mongrel recipient dog weighing 20~25 kg. Gadolinium Chloride (10 mg/kg) was infused via the cephalic vein 24 hour before harvesting the partial liver (Gadolinium group, n=5). Serum Aspartate Aminotransferase (AST) Alkaline phosphatase (ALP), Lactate dehydrogenase (LDH), and morphological grading of the graft were compared with the control group (n=5). Statistical analysis was done with an independent T-test. RESULTS: The total ischemic time was 4 hours and 27 minutes on average. One hour after reperfusion, there were no significant differences in the AST, ALP and LDH level, and the pathologic scores. At 48 hours after reperfusion, the AST (P=0.03) and LDH (P=0.05) levels were significantly lower in Gadolinium group. CONCLUSION: Kupffer cell blockage using the Gadolinium chloride might be an effective way of reducing ischemia reperfusion injury. However, this effect was not evident in the early stages of reperfusion.

The Effect of Lipo-PGE1 on Ischemia-Reperfusion Injury and Endothelin-1 Concentrations After Canine Partial Liver Transplantation / 대한간학회지

BACKGROUND/AIM: The lipo-PGE1, known for being more stable during pulmonary circulation and having more targeting effect, has been reported to inhibit ET-1 induced stellate cell contraction. We assessed the effect of lipo-PGE1 on the change of ET-1 concentration and the relationship between ET-1 concentration and the liver damage. METHODS: Mongrel dogs weighing about 25 kg were divided into a control (n=6) and a lipo-PGE1 (n=6) group. Partial liver allotransplantation was performed. In the lipo-PGE1 group, lipo-PGE1 was slowly infused through splenic venous cannulation during the donor liver harvesting procedure (50 microgram) and continuously infused (60 microgram/day) for 48 hours after reperfusion. The AST, ALP, LDH and ET-1 concentrations were monitored RESULTS: The AST and ALP levels of the lipo-PGE1 group were significantly lower than those of the control group both at 1 hour and 48 hours after reperfusion. The LDH level in the lipo-PGE1 group was lower at 1 hour and 48 hours after reperfusion. But there was no statistical difference between the two groups. The baseline ET-1 concentration of the lipo-PGE1 group was eight times higher than that of the control group. The ET-1 concentration was elevated gradually in the control group. There was no significant difference between the two groups at 48 hours. There was no correlation between ET-1 concentrations and AST, ALP, LDH levels. CONCLUSION: This study demonstrated the hepatoprotective effect of the lipo-PGE1 against ischemia-reperfusion injury in canine partial liver allotransplantation. However, the baseline ET-1 level was eight times higher in the lipo-PGE1 group than that of the control group in spite of the hepatoprotective effects of the lipo-PGE1.

The Effect of Lipo-PGE1 in Canine Partial Liver Allograft Model / 대한이식학회지

PURPOSE: Hepatoprotective effect of prostaglandin E1 (PGE1) has been verified in numerous animal experiments but not so apparent in clinical trials. Although the reason for this discrepancy in clinical results is still unknown, one possible explanation is the instability of PGE1. In this study, the hepatoprotective effect of lipo-PGE1, which is known to be stable during pulmonary circulation and have more targeting effect, was investigated in canine partial liver allotansplantation. In order to reckon in the possible injury during harvest of partial liver, lipo-PGE1 was infused from the start of living graft harvest procedure. METHODS: Mongrel dogs weighing about 25 kg were divided into control (n=6) and lipo-PGE1 (n=6) group. Partial liver allotransplantation was performed. In lipo-PGE1 group, lipo-PGE1 was slowly infused through splenic venous cannulation during the donor liver harvesting procedure (50 mg) and continuously infused (60 mg/day) for 48 hrs after reperfusion. The aspartate aminotransferase (AST), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) were monitored. RESULTS: The AST and ALP levels of the lipo-PGE1 group were significantly lower than that of the control group at both 1 hour and 48 hours after reperfusion. The LDH level in lipo-PGE1 group was lower at 1 hour and 48 hours after reperfusion, but no significant differences were shown between two groups. CONCLUSION: This study demonstrated the hepatoprotective effect of the lipo-PGE1 against ischemia-reperfusion injury in canine partial liver allotransplantation.