Katsuhiko Yanaga

[d-Ala2, d-Leu5] enkephalin (DADLE) protects liver against ischemia-reperfusion injury in the rat

BACKGROUND [D-Ala(2), D-Leu(5)] enkephalin (DADLE) is a synthetic delta class of opioid and is reported to induce hibernation as well as hibernation induction trigger (HIT) in the serum of hibernating mammals. DADLE and HIT have been demonstrated to protect the heart, lung, and jejunum against ischemia-reperfusion (I-R) injury. In the present study, we examined the effect of DADLE on I-R injury of the liver in rats. METHODS After administration of DADLE (DADLE group) or normal saline as a vehicle (Control group), partial hepatic ischemia was induced by occluding the vessels supplying 92% of the liver for 45 min, followed by declamping the vessels and resection of the non-ischemic lobe. After 120 min of reperfusion, serum glutamic-pyruvic transaminase (GPT), hyaluronic acid (HA) levels, and concentrations of malondialdehyde (MDA) of the liver tissue were measured. Additionally, bile output from the ischemic lobes was measured after reperfusion. RESULTS GPT levels were significantly lower in the DADLE group as compared to those of the Control group (P < 0.05), but the serum levels of HA were not different between the two groups. The concentrations of MDA of the liver tissue were significantly lower in the DADLE group than in the Control group (P < 0.01). The bile output after reperfusion was not significantly different between the two groups. CONCLUSIONS DADLE protects against I-R injury in hepatocytes, but not in the sinusoidal endothelial cells of the liver in rats. An anti-oxidative effect is suggested to be responsible for this effect.

A New Liver Perfusion and Preservation System for Transplantation Research in Large Animals

A kidney perfusion machine, model MOX-100 (Waters Instruments, Ltd, Rochester, MN) was modified to allow continuous perfusion of the portal vein and pulsatile perfusion of the hepatic artery of the liver. Additional apparatus consists of a cooling system, a membrane oxygenator, a filter for foreign bodies, and bubble traps. This system not only allows hypothermic perfusion preservation of the liver graft, but furthermore enables investigation of ex vivo simulation of various circulatory circumstances in which physiological perfusion of the liver is studied. We have used this system to evaluate the viability of liver allografts preserved by cold storage. The liver was placed on the perfusion system and perfused with blood with a hematocrit of approximately 20%, and maintained at 37 degrees C for 3 h. The flows of the hepatic artery and portal vein were adjusted to 0.33 mL and 0.67 mL/g of liver tissue, respectively. Parameters of viability consisted of hourly bile output, oxygen consumption, liver enzymes, electrolytes, vascular resistance, and liver histology. This method of liver assessment in large animals will allow the objective evaluation of organ viability for transplantation and thereby improve the outcome of organ transplantation. Furthermore, this pump enables investigation into the pathophysiology of liver ischemia and preservation.

Immunodepletion in Xenotransplantation

Xenograft transplantation is perhaps the most immunologically difficult problem in transplantation today. An overwhelming hyperacute rejection reaction (HAR) occurs within minutes of organ implantation. Preformed antibodies are thought to initiate this process. We used a pig-to-dog renal xenograft transplant model and investigated methods of decreasing the severity of hyperacute rejection. Female pigs weighing 15-20 kg were used as donors. Recipients were mongrel dogs weighing 15-25 kg. Experimental dogs were all given a number of treatments of IgG depletion using an antibody removal system (Dupont-Excorim). This machine immunoadsorbs plasma against a column containing immobilized staphylococcal protein A, which is known to bind the IgG Fc receptor. An 84% reduction in the IgG levels and a 71% reduction in IgM levels was achieved. Postoperative assessment was made of urine output, time to onset of HAR, and histopathological examination of the rejected kidneys. Although cross-matches between donor lymphocytes and recipient sera remained strongly positive in the treated dogs, there was a two- to fourfold reduction in the titers. The time to onset of HAR was prolonged in the experimental group, and the urine output was increased slightly. The histopathologic changes in the experimental group generally showed signs of HAR, but of less intensity than in the nonimmunodepleted control group.

Duct‐to‐duct biliary reconstruction in adult‐to‐adult living donor liver transplantation

Takatsuki M, Yanaga K, Okudaira S, Furui J, Kanematsu T. Duct‐to‐duct biliary reconstruction in adult‐to‐adult living donor liver transplantation. Clin Transplant 2002: 16: 345–349.

Glycine reduces hepatic warm ischaemia-reperfusion injury by suppressing inflammatory reactions in rats.

Background: Glycine, a non‐essential amino acid, is known to have an anti‐inflammatory effect on haemorrhagic and endotoxic shock in animals. In the present study, we examined the effects of glycine on inflammatory reactions and hepatocellular damage after hepatic warm ischaemia–reperfusion (I–R) in rats.

Inactivation of porcine endogenous retrovirus by human serum as a function of complement activated through the classical pathway

BACKGROUND: The clinical use of organs and cells of pig donors as a source of tissue for xenotransplantation and extracorporeal therapies has been problematic due to the risk for zoonotic infection of porcine endogenous retroviruses (PERV). METHODS: The effect of human serum on PERV was evaluated using an infectivity assay and virolysis assay. Cell-free PERV infection to human 293 cells was determined by the presence of proviruses 5 days post-infection by a highly sensitive nested PCR, and the lysis of PERV virions was determined by the reverse transcriptase activities released into the supernatant. RESULTS: Treatment of PERV-PK, the culture supernatant of a pig kidney cell line containing the virus titer of 10(2.8) TCID(50) units/ml, with a quarter volume of human serum completely inactivated the infectivity. This activity was heat-labile and sensitive to an anti-complement agent, nafamostat mesilate, and a Ca(2+)-chelator, EGTA, indicating the crucial involvement of complement activated through the classical pathway. Since a synthetic galactosyl alpha1-3 galalactose (Galalpha1-3Gal) largely absorbed the activity from the serum, natural antibodies to the Galalpha1-3Gal epitopes are likely to trigger the complement activation. CONCLUSION: Cell-free PERV seems no longer be infectious in human serum. This greatly encourages the clinical application of pig tissues in particular for extracorporeal therapies such as a bioartificial liver, in which pig cells do not come in direct contact with a recipient.

Role of intrasplenic hepatocyte transplantation in improving survival and liver regeneration after hepatic resection in cirrhotic rats.

We studied the effect of preoperative hepatocyte transplantation on the prevention of liver failure in cirrhotic rats after hepatic resection. Two groups of Lewis rats were rendered cirrhotic by IP injection of 1% dimethylnitrosamine and were subjected to 33% hepatectomy. Two days before the resection, 36 rats in group I received intrasplenic hepatocyte transplantation, and 25 rats in group II were given intrasplenic injection of normal saline as a control. By the end of the third postoperative day, the rats in group I had better survival and a better biochemical profile than those in group II. The liver growth rate and the labeling index of proliferating cell nuclear antigen (PCNA-LI) showed a steady rise in group I. Compared with group II, group I had a significantly lower transforming growth factor (TGF-β1) level (p < 0.05). We conclude that preoperative intrasplenic hepatocyte transplantation improves survival and facilitates regeneration in cirrhotic rats after hepatic resection.

A new suppressive agent against interleukin-1β and tumor necrosis factor-α enhances liver regeneration after partial hepatectomy in rats

In the present study, the effect of FR167653, a novel suppressive agent against interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha), on liver regeneration was investigated in rats after partial hepatectomy (PH). Doses of 1, 3 and 5 mg/kg per h FR167653 (FR-1, FR-3 and FR-5, respectively) were given intravenously 30 min before PH, while the control was given normal saline. Serum chemistries were serially monitored, and liver regeneration was evaluated by remnant liver weight ratio, proliferating cell nuclear antigen (PCNA) labeling index and mitotic index. Accumulation of IL-1beta and TNF-alpha messenger RNA (mRNA) in the remnant liver was also measured. In FR167653-treated groups, the releases of alanine transaminase (ALT) and aspartate transaminase (AST) were lower. The PCNA labeling index was enhanced by FR167653-administration in a dose-dependent manner, FR-3 and FR-5 groups showed significantly higher peak DNA synthesis than the control group at 24 h post-PH (P<0.01). The mitotic index was also enhanced by FR167653-administration in a dose-dependent manner. In FR-5 group, the remnant liver weight ratio was significantly higher than that in the control group (P<0.05). The accumulation of IL-1beta messenger RNA (mRNA) in the remnant liver was obviously suppressed in FR-3 and FR-5 groups, but the expression of TNF-alpha mRNA was not apparently reduced. In conclusion, FR167653 ameliorates liver injury and enhances liver regeneration after PH in rats.

Pretransplant assessment of human liver grafts by plasma lecithin: cholesterol acyltransferase (LCAT) activity in multiple organ donors.

In spite of the improved outcome of orthotopic liver transplantation (OLTx), primary graft nonfunction remains one of the life-threatening problems following OLTx. The purpose of this study was to evaluate plasma lecithin: cholesterol acyltransferase (LCAT) activity in multiple organ donors as a predictor of liver allograft viability prior to OLTx. Thirty-nine donors were studied during a 5-month period between April and August 1988. Allograft hepatectomy was performed using a rapid technique or its minor modification with hilar dissections, and the allografts were stored cold (4°C) in University of Wisconsin (UW) solution. Early post-transplant allograft function was classified as good, fair, or poor, according to the highest SGOT, SGPT, and prothrombin time within 5 days following OLTx. Procurement records were reviewed to identify donor data, which included conventional liver function tests, duration of hospital stay, history of cardiac arrest, and graft ischemic time. Blood samples from the donors were drawn immediately prior to aortic crossclamp, and from these plasma LCAT activity was determined. Plasma LCAT activity of all donors was significantly lower than that of healthy controls (12.4±8.0 vs 39.2±13.3 μg/ml per hour, P<0.01). LCAT activity (16.4±8.3 μg/ml per hour) in donors of grafts with good function was significantly higher than that in those with fair (8.6±4.5 μg/ml per hour, P<0.01) or poor (7.3±2.4 μg/ml per hour, P<0.01) function. Information regarding procurement, which was complete in the records of 31 of 39 donors, was used in a multiple logistic regression analysis that revealed plasma LCAT activity to be the only factor able to discriminate the quality of the hepatic graft from other variables in multiple organ donors. The present study suggests that the determination of plasma LCAT activity in multiple organ donors is extremely useful for the assessment of hepatic allograft viability prior to OLTx.

Successful Left Adrenalectomy for Metastatic Hepatocellular Carcinoma Using Hand-Assisted Laparoscopic Surgery: Report of a Case

A 56-year-old man diagnosed a having multiple hepatocellular carcinoma (HCC) with liver cirrhosis underwent transcatheter arterial embolization (TAE). Five months later, recurrent HCC was detected in the liver as well as in the left adrenal gland. A second TAE was performed to treat the intrahepatic recurrence, which was followed by hand-assisted laparoscopic surgery (HALS) for the metastatic tumor in the left adrenal gland. The combination of the two procedures successfully controlled HCC. To our knowledge, this is the first report describing an adrenalectomy by HALS for adrenal metastasis from an HCC.