Phase II trial of combination therapy of gemcitabine plus anti-angiogenic vaccination of elpamotide in patients with advanced or recurrent biliary tract cancer.

Background Elpamotide is an HLA-A*24:02-restricted epitope peptide of vascular endothelial growth factor receptor 2 (VEGFR-2) and induces cytotoxic T lymphocytes (CTLs) against VEGFR-2/KDR. Given the high expression of VEGFR-2 in biliary tract cancer, combination chemoimmunotherapy with elpamotide and gemcitabine holds promise as a new therapy. Patients and Methods Patients with unresectable advanced or recurrent biliary tract cancer were included in this single-arm phase II trial, with the primary endpoint of overall survival. Survival analysis was performed in comparison with historical control data. The patients concurrently received gemcitabine once a week for 3 weeks (the fourth week was skipped) and elpamotide once a week for 4 weeks. Results Fifty-five patients were registered, of which 54 received the regimen and were included in the full analysis set as well as the safety analysis set. Median survival was 10.1 months, which was longer than the historical control, and the 1-year survival rate was 44.4%. Of these patients, injection site reactions were observed in 64.8%, in whom median survival was significantly longer (14.8 months) compared to those with no injection site reactions (5.7 months). The response rate was 18.5%, and all who responded exhibited injection site reactions. Serious adverse reactions were observed in five patients (9%), and there were no treatment-related deaths. Conclusion Gemcitabine and elpamotide combination therapy was tolerable and had a moderate antitumor effect. For future development of therapies, it will be necessary to optimize the target population for which therapeutic effects could be expected.

Probe of the solar magnetic field using the "cosmic-ray shadow" of the sun.

We report on a clear solar-cycle variation of the Sun's shadow in the 10 TeV cosmic-ray flux observed by the Tibet air shower array during a full solar cycle from 1996 to 2009. In order to clarify the physical implications of the observed solar cycle variation, we develop numerical simulations of the Sun's shadow, using the potential field source surface model and the current sheet source surface (CSSS) model for the coronal magnetic field. We find that the intensity deficit in the simulated Sun's shadow is very sensitive to the coronal magnetic field structure, and the observed variation of the Sun's shadow is better reproduced by the CSSS model. This is the first successful attempt to evaluate the coronal magnetic field models by using the Sun's shadow observed in the TeV cosmic-ray flux.

Interventional radiology for hepatic artery complications soon after living donor liver transplantation in a neonate.

Early hepatic artery complications after liver transplantation in children, having undergone LDLT, can directly affect graft and recipient outcomes, making early diagnosis and treatment essential. In the past, laparotomy (thrombectomy or reanastomosis) was generally employed to treat early hepatic artery complications. Recently, favorable outcomes of IR have been reported. In children, however, the number of such reports is small. To the best of our knowledge, there is no published report on IR applied to neonates with early hepatic artery complications. We recently succeeded in safely using IR for a neonate with early hepatic artery complications after LDLT and obtained a favorable outcome. This case is presented herein.

Hepatic artery reconstruction with the jejunal artery of the Roux-en-Y limb in pediatric living donor liver re-transplantation.

When re-anastomosis and re-transplantation becomes necessary after LDLT, arterial reconstruction can be extremely difficult because of severe inflammation and lack of an adequate artery for reconstruction. Frequently, the recipient's HA is not in good condition, necessitating an alternative to the HA. In such cases, the recipient's splenic artery, right gastroepiploic artery or another vessel can be safely used for arterial reconstruction. There have, however, been few reports on using the jejunal artery. Herein, we report our experience with arterial reconstruction using the jejunal artery of the Roux-en-Y limb as an alternative to the HA. A three-yr-old girl who had developed graft failure due to early HA thrombosis after LDLT required re-transplantation. At re-transplantation, an adequate artery for reconstruction was lacking. We reconstructed the artery by using the jejunal artery of the Roux-en-Y limb, as we judged it to be the most appropriate alternative. After surgery, stent was deployed because hepatic blood flow had reduced due to kinking of the anastomosed site, and a favorable outcome was obtained. In conclusion, when an alternative to the HA is required, using the jejunal artery is a feasible alternative.

Living donor liver transplantation from an asymptomatic mother who was a carrier for ornithine transcarbamylase deficiency.

Liver transplantation (LT) has been adopted as a radical treatment for ornithine transcarbamylase deficiency (OTCD), yielding favorable outcomes. Despite the fact that it is an inheritable disease, a blood relative who is heterozygous for the disorder must sometimes be used as a liver donor for living donor LT. There is ongoing discussion regarding the use of heterozygous donors, however, to our knowledge, no cases where donation was determined based on the Ornithine transcarbamylase (OTC) activity before LT have been reported. Between May 2001 and April 2011, 17 patients were indicated for living donor LT because of OTCD at our facility. There were three cases with heterozygous donor candidate (17.6%). All heterozygous candidates underwent a liver biopsy to measure their OTC activity before LT and made efforts to secure the safety of the both donor and recipient. Two of 3 candidates had headaches sometimes, and their activity was less than 40%, and thus they were not employed as the donor. One candidate with 104.4% activity was employed, yielding favorable outcomes. Our current experience supported the effectiveness of our donation criteria, however it is necessary to collect sufficient data on a large number of patients to confirm the safety of the procedure.

Living donor liver transplantation for ornithine transcarbamylase deficiency.

Ornithine transcarbamylase deficiency, the most common urea cycle disorder, causes hyperammonemic encephalopathy and has a poor prognosis. Recently, LT was introduced as a radical OTCD treatment, yielding favorable outcomes. We retrospectively analyzed LT results for OTCD at our facility. Twelve children with OTCD (six boys and six girls) accounted for 7.1% of the 170 children who underwent LDLT at our department between May 2001 and April 2010. Ages at LT ranged from nine months to 11 yr seven months. Post-operative follow-up period was 3-97 months. The post-operative survival rate was 91.7%. One patient died. Two patients who had neurological impairment preoperatively showed no alleviation after LT. All patients other than those who died or failed to show recovery from impairment achieved satisfactory quality-of-life improvement after LT. The outcomes of LDLT as a radical OTCD treatment have been satisfactory. However, neurological impairment associated with hyperammonemia is unlikely to subside even after LT. It is desirable henceforth that more objective and concrete guidelines for OTCD management be established to facilitate LDLT with optimal timing while avoiding the risk of hyperammonemic episodes.

Living donor liver transplantation for a child with recurrent pediatric adult-type hepatocellular carcinoma.

INTRODUCTION: Pediatric hepatocellular carcinoma (HCC) is an uncommon disease with a poor prognosis. There are few reports about liver transplantation for pediatric adult-type HCC. We experienced a case of living donor liver transplantation (LDLT) for a child with recurrent pediatric adult-type HCC. CASE REPORT: A 12-year-old boy was admitted to the Department of Pediatrics in our institution due to HCC in May 2005. He underwent hepatectomy after 3 courses of chemotherapy in July 2005. After the operation, he had 2 more courses of the same chemotherapy. His posttheraputic course was uneventful for 1 year. However, his alpha-fetoprotein level increased and a computed tomography (CT) scan showed recurrent tumor in his remnant liver in October 2006. He underwent another chemotherapy session immediately. However, CT revealed multiple liver tumors after chemotherapy in December 2006. His mother requested to be an LDLT donor, which was performed on January 23, 2007. The donor operation was a right hepatic lobectomy. The postoperative course of the donor was unremarkable and she has now returned to work. The recipient's posttransplantation course was uneventful and he was discharged at postoperative day 53 and is currently doing well. CONCLUSION: Liver transplantation in conjunction with chemotherapy may have an increasing role in the management of pediatric HCC.

Timing for orthotopic liver transplantation in children with biliary atresia: a single-center experience.

INTRODUCTION: Biliary atresia is the most common indication for orthotopic liver transplantation (OLT) in childhood. The purpose of this study was to determine predictive prognostic factors for children with biliary atresia related to the timing for OLT within 15 months after hepatoportoenterostomy (HPE). PATIENTS AND METHODS: We retrospectively analyzed the medical records of 25 children (7 boys and 18 girls) who underwent HPE because of biliary atresia between January 1990 and December 2005 at our center. Data examined included age and pathologic findings at HPE, Pediatric End-Stage Liver Disease score at first admission, whether phototherapy was given, liver function test results and total bilirubin level before and 30 days after HPE, and number of cholangitis events. RESULTS: Twelve children were alive with their native liver, 8 had undergone living donor OLT (all children alive), and 5 had died without OLT. Five- and 10-year survival rates without OLT after HPE were 47.4% and 26.3%, respectively. At univariate analysis, the predictive prognostic factors for children with biliary atresia were total bilirubin level at 30 days after HPE and Pediatric End-Stage Liver Disease score before HPE. At multivariate analysis, the only prognostic factor was total bilirubin level at 30 days after HPE. CONCLUSIONS: In this study, the predictive prognostic factor was total bilirubin level at 30 days after HPE. Orthotopic liver transplantation within 15 months after HPE is needed in children with biliary atresia with a high total bilirubin level at 30 days after HPE.

Impact of Smoking Cessation in Donor Candidates for Living Donor Liver Transplantation.

BACKGROUND: The relationship between smoking cessation and weight gain is well recognized. Examining the link between smoking cessation and weight gain in donor candidates for living donor liver transplantation (LDLT) is an important topic because of the influence of weight gain on the liver. This study assessed body weight (BW) changes after smoking cessation in donor candidates for LDLT. METHODS: The 27 donor candidates were retrospectively analyzed. The smoking status was determined based on questionnaires administered at the initial presentation, and the candidates were divided into 2 groups: recent quitters and nonsmokers. The changes in BW were compared between the groups. RESULTS: The recent quitters group included 10 (37.0%) candidates, and the nonsmokers group included 17 (63.0%). In the nonsmokers group, 1 candidate had gained weight since the initial presentation. In contrast, in the recent quitters group, 70.0% of candidates had gained weight since the initial presentation (P < .01). The change in BW from the initial presentation was greater in recent quitters than in nonsmokers (+1.6 kg [+2.4%] vs -0.5 kg [-0.9%]; P < .01). Two candidates in the recent quitters group gained ≥ 5 kg [8%] of weight. One of these 2 candidates was judged to be in a donor-inadequate status because of the appearance of fatty liver. CONCLUSIONS: Weight gain due to smoking cessation was observed in donor candidates for LDLT. The amount of weight gain after smoking cessation is highly individualized, so everyone concerned with LDLT must be alert to its potential development.

Long-term Changes in Spleen Volume After Living Donor Liver Transplantation in Pediatric Recipients.

BACKGROUND: Living donor liver transplantation (LDLT) is a definitive procedure for splenomegaly caused by liver cirrhosis and portal hypertension, but splenomegaly persists in some patients. The aim of this study was to clarify the long-term changes in the spleen volume after LDLT. METHODS: The 13 pediatric patients who survived for >8 years after LDLT were retrospectively analyzed. We calculated the spleen volume/standard spleen volume (SV/SSV) ratio by automated computed tomography (CT) volumetry. We assessed the spleen volumes before LDLT, at roughly postoperative week (POW) 4, at postoperative year (POY) 1, at POY 5, and at POY 10. RESULTS: With regard to SV as evaluated by CT volumetry, there were no consistent trends, with median values as follows: before LDLT, 282.5 (71-641) cm3; POW 4, 252 (109-798) cm3; POY 1, 222.5 (97-948) cm3; POY 5, 263.5 (123-564) cm3; and POY 10, 377 (201-1080) cm3. In contrast, the SV/SSV ratio decreased chronologically as follows: before LDLT, 5.0 (0.7-6.0); POW 4, 3.7 (2.3-4.3); POY 1, 2.2 (1.7-6.3); POY 5, 1.7 (1.1-5.4); and POY 10, 1.4 (1.1-6.9). In the remote phase after LDLT, many cases showed a trend toward an improved SV/SSV ratio, but splenomegaly was prolonged without improvement in 3 cases (23.1%) with portal vein complications and advanced fibrosis. Furthermore, all 3 cases showed a decreased platelet count due to hypersplenism. CONCLUSION: Splenomegaly requires a long time to demonstrate an improvement. In cases without an improvement of splenomegaly, we should suspect abnormalities in the graft liver and portal hemodynamics.

Living-Donor Liver Transplantation With the Use of a Left-Lobe Graft From a Donor With Anomalous Biliary Anatomy in Which B4 Joins the Right Anterior Sectional Duct: A Case Report.

When there is an anatomic anomaly in the biliary tract of the donor for living-donor liver transplantation, the risk of postoperative biliary tract complications increases in both the donor and the recipient. We studied a case of living-donor liver transplantation with a left hepatic lobe graft that had anatomic anomalies, in which the medial segmental branch (B4) joined the anterior segmental branch and the posterior segmental branch formed a common trunk with the lateral segmental branch. A 40-year-old man visited our institution as a candidate organ donor for his mother, who had end-stage liver failure. An anomaly of B4 connecting the anterior segmental branch was suspected on magnetic resonance cholangiopancreatography. On intraoperative cholangiography, confluence of B4 with the anterior segmental branch and connection of the posterior and lateral segmental branches forming a common trunk were confirmed. Accordingly, individual anastomoses of the lateral segmental branch and B4 with the recipient jejunum were planned, and a left-lobe graft was excised. The postoperative recovery was smooth, and the donor was discharged with no complications. Even when an anatomic anomaly is present in the donor bile duct, in urgent cases, accurate evaluation through the use of various modalities may enable living-donor liver transplantation with the use of a graft with an anatomic anomaly.

Warm ischemia and reperfusion injury in diet-induced canine fatty livers.

BACKGROUND: Fatty liver is associated with primary nonfunction after liver transplantation, contributing a shortage of suitable liver grafts. Because extensive investigation of mechanisms underlying such nonfunction has been limited largely to rodents, we made a new fatty liver model in dogs and studied primary nonfunction after warm ischemia. METHODS: We developed a diet rich in fat but deficient in choline to induce fatty change in canine liver and investigated effects of 60 min of warm ischemia and reperfusion in dogs with such fatty livers. RESULTS: Microscopically evident steatosis increased with duration of dietary manipulation (up to 12 weeks), as did hepatic total lipid and triglyceride levels. No dog with >30% of steatotic hepatocytes, >445 mg/g hepatic total lipid or >145 mg/g hepatic triglyceride survived after 60 min of warm ischemia. Arterial ketone body ratios decreased and blood endotoxin increased after reperfusion in nonsurvivors. The main histologic finding in livers of nonsurvivors was marked sinusoidal congestion. CONCLUSIONS: Damage to hepatocytes and nonparenchymal cells after warm ischemia and reperfusion was thought to be closely related to sinusoidal microcirculatory disturbances in fatty livers. The canine fatty liver model reported here may be useful in studying the pathology of primary nonfunction and in establishing criteria for allowable degrees of fatty change in potential liver grafts.

Efficacy of double filtration plasmapheretic cross-circulation using a high permeability membrane between totally hepatectomized dogs and donor pigs.

BACKGROUND: Major obstacles to develop a bioartificial liver are xenogeneic immune reactions and viral infection from donor pigs. To solve these problems, we studied the effect of xenogeneic double filtration plasmapheretic cross-circulation (DFPCC) using a high performance semipermeable membrane on totally hepatectomized dogs. METHODS: Mongrel dogs, weighing 12-15 kg, underwent total hepatectomy in one stage (n=18). One hr after total hepatectomy, the femoral vein and the jugular vein were cannulated in both dogs and pigs by using the blood access catheter tubes that were connected to the DFPCC system. In the DFPCC circuit, filtrated dog plasma and pig plasma counterflowed in a hollow fiber cartilage at a rate of 25 ml/min for 6 hr and met through a semipermeable membrane with 100 kd nominal molecular weight cut-off (n=5). In control dogs, the circuit was not connected to the pig (n=13). RESULTS: In vitro mass transfer study suggested that very little immunoglobulins crossed the semipermeable membrane. During and after 6 hr of DFPCC, anhepatic dogs had significantly lower blood ammonia and aromatic amino acid levels than did controls. DFPCC-treated dogs demonstrated decreased intracranial pressure and survived significantly longer than control dogs (20.75+/-3.80 hr vs. 14.75+/-1.30 hr, P<0.05). Histology showed no xenogeneic rejection in both dogs and pigs. CONCLUSIONS: Our DFPCC systems with a high permeability membrane demonstrated detoxification-function and contributed to intracranial decompression and longer animal survivals without adverse immune reaction and the possibility of zoonosis.

Improved survival and ammonia metabolism by intraperitoneal transplantation of microencapsulated hepatocytes in totally hepatectomized rats.

BACKGROUND: We evaluated the effects of intraperitoneal transplantation of microencapsulated hepatocytes in a 3-stage total hepatectomy rat model. METHODS: A new model of total hepatectomy was created as follows. First, the infrahepatic inferior vena cava was ligated just above the right renal vein. Seven days later, the portal vein was ligated and a portacaval shunt was established using a Teflon catheter over a venipuncture needle. Another 7 days later, total hepatectomy was completed by ligating and dividing the suprahepatic inferior vena cava, the hepatic artery, and the bile duct. Next, 4 x 10(7) hepatocytes (4% of the normal liver hepatocyte mass) isolated from male Wistar rats were microencapsulated within a collagen matrix enveloped by a 3-layer membrane of sodium alginate-poly-L-lysine-sodium alginate copolymer. Capsules containing hepatocytes (diameter, 500-800 microm) and empty capsules (control) were transplanted intraperitoneally 4 days before the total hepatectomy. Survival time and selected blood chemistry concentrations after the total hepatectomy were measured. The capsules were also examined histologically with hematoxylin and eosin staining and modified Gmelin's stain for bile pigments. RESULTS: The survival time was greater in the rats given the microencapsulated hepatocytes than in the control rats (17.3 +/- 3 vs 3.7 +/- 0.1 hours; P <.01). The blood ammonia concentrations increased soon after total hepatectomy but remained significantly lower in the rats with microencapsulated hepatocytes (P <.05). The microcapsules contained numerous viable hepatocytes with abundant bile pigments and no lymphocytic infiltration. CONCLUSIONS: Microencapsulated hepatocytes with an ultrathin polymer layer that protects them from inflammatory and lymphocytic reactions may facilitate their ability to function. In this study, 4 x 10(7) hepatocytes significantly prolonged the survival of rats that underwent hepatectomy and supported ammonia metabolism. Further development of this technique may permit its use in patients with hepatic failure.

Late development of bile duct cancer after sphincteroplasty: a ten- to twenty-two-year follow-up study.

BACKGROUND: Transduodenal sphincteroplasty is designed to destroy the sphincteric muscle fibers, producing a terminal choledochoduodenostomy. In the absence of Oddi's sphincter, intestinal contents with both activated pancreatic juice and bacterial flora are refluxed into the bile duct and remain there for a prolonged time. The long-term effect of producing the reflux has not been evaluated to date. METHODS: One hundred nineteen consecutive patients undergoing transduodenal sphincteroplasty between February 1973 and July 1984 were included in this study. Postoperative clinical courses of 108 patients could be evaluated by means of a retrospective review of the hospital records. Median follow-up was 18 years. RESULTS: Eight cases (7.4%) of primary bile duct cancer were found among the 108 cases at intervals of 1 to 20 years after sphincteroplasty. Two patients had concurrent hepatolithiasis. The patency of sphincteroplasty was confirmed in all cases, and the bile was infected in seven cases. Pathologic specimens obtained demonstrated cholangiocarcinomas and various degrees of atypical hyperplastic lesions under the background of chronic cholangitis. CONCLUSIONS: Chronic cholangitis can be an important causative factor in late development of bile duct cancer after sphincteroplasty. Any patients treated with choledochoduodenostomy should be closely monitored for late cholangiocarcinoma.

Radiation-inducible TNF-alpha gene expression under stress-inducible promoter gadd 153 for cancer therapy.

We demonstrated the effectiveness of radiation-inducible expression of the TNF-alpha gene for cancer therapy in vitro. The TNF-alpha gene under the control of the stress-inducible promoter, gadd 153, was introduced into the human glioma cell line, U251-SP. Without cobalt-60 gamma irradiation, no cytotoxicity against the transfected cells was observed. When the transfected cells were irradiated with 10 or 20 gray (Gy), the gadd 153 promoter was highly induced and the expression level of TNF-alpha increased. Five days after the irradiation, the TNF-alpha productions of each cell irradiated with 10 and 20 Gy were 30 and 100 times higher than the basal level, respectively. The cytotoxicities against the transfected cells 5 d after irradiation with 10 and 20 Gy were 79% or 91%, respectively, which are much higher than those against the nontransfected cells that were irradiated at the same dose (43% and 78%, respectively). These results demonstrate that the gadd 153-TNF-alpha system may be an effective tool for radiosurgery of malignant brain tumors.

Primary immunosuppression regimen of rapid steroid withdrawal after living related liver transplantation: a single-center experience.

AIM: Corticosteroids have been considered the mainstay of immunosuppressive therapy after liver transplantation. However, the side effects of long-term steroid use such as diabetes, infections, and bone disease, including growth retardation in children, are serious problems. Our immunosuppression regimen includes FK506 and steroid withdrawal by 30 days after transplantation. The aim of this study was to determine the outcomes of liver transplant, using this immunosuppressive regimen. PATIENTS: Fifteen primary liver transplant recipients were performed between January 1994 and May 2003 and data were reviewed retrospectively. Eight pediatric and four adult recipients, who had survived more than 3 months after transplantation, were included in this sample. The immunosuppressive regimen consisted of FK 506 (Prograf), initially at doses of 0.03 mg/kg, with dose adjustments to achieve daily trough levels of approximately 10 to 12 ng/mL, and predonisone, initially at 4 mg/kg/d, with a taper and cessation by 30 days when the graft was stable. RESULTS: All recipients were successfully withdrawn by 30 days. Acute rejection episodes occurred in three patients, no patient was diagnosed with chronic rejection. The acute rejection-free rate at 5 year was 74.1%. No recipient had diabetes, serious infections or bone disease. CONCLUSION: Our primary immunosuppressive regimen of rapid steroid withdrawal is safe with regard to acute and chronic rejection with benefits upon steroid-related side effects.

In vitro evaluation of cross-circulation system using semipermeable membrane combined with whole liver perfusion.

INTRODUCTION: Many types of isolated hepatocytes-based bioartificial liver have been developed. However, to maintain hepatocyte-specific functions for a long period is still a significant challenge. The possibilities of rejection or viral transmission still remain as untackled obstacles. We developed a cross-circulation system, using a semipermeable membrane combined with whole liver perfusion. Detoxifying functions of the extracorporeal porcine liver and molecular movements across the membrane were evaluated in vitro. METHODS: The hollow-fiber module has a molecular cutoff of 100 kD. A spiked solution containing 500 mL low molecular dextran solution spiked with 12 mg ammonium chloride, 500 mg D-galactose, and 300 mg lidocaine, which mimicked a patient, was recirculated through the inner fiber space. The extracorporeal liver perfusion circuit consisted of an extra-fiber spaces. A reservoir containing 1000 mL healthy pig plasma, a membrane oxygenator, and a porcine whole liver. Both circuits circulated in the opposite direction for 6 hours. RESULT: In 6 hours, 47.3% +/- 10.2% of ammonia, 89.5% +/- 1.7% of D-galactose, and 95.5% +/- 1.0% of lidocaine were eliminated from the circuits; 66.5 +/- 11.1 mg of urea were produced at the same time. Oxygen consumption was maintained between 0.248 and 0.259 mL/100 g liver/min for 6 hours. Movement of IgM was completely blocked by the 100-kD membrane, whereas albumin was freely transferred from the reservoir to the intrafiber space. CONCLUSION: The perfusion experiments showed the possibility of using a whole liver with oxygenated plasma perfusion in a bioartificial liver system in vitro.

CD8 T cell of donor splenocyte mixed with bone marrow cells is more effective than CD4 T cell for induction of donor-specific tolerance in sublethally irradiated mice.

BACKGROUND: We previously demonstrated that even a low dose of bone marrow cells (BMCs) established donor-specific tolerance if mixed with splenocytes (SPLCs). In this study, T-cell subsets CD4 (CD4SP) and CD8 (CD8SP) of donor SPLCs were investigated for their contribution to the enhancement of BMC engraftment leading to donor-specific tolerance in sublethally irradiated mice. METHODS: Sublethally irradiated C57BL/6 recipient mice were intravenously injected BMCs mixing with CD4SP or CD8SP harvested from BALB/c donor mice. The degree of chimerism in the peripheral blood lymphocytes (PBLs) and in the SPLCs was analyzed using FACS, mixed lymphocyte reaction, and skin graft transplantation 3 months after injection. RESULTS: Recipients injected with 3 x 10(6) donor BMCs admixed with 10 x 10(6) donor CD8SP established chimerism. However, recipients injected with the same dose of BMCs admixed with 5 x 10(6) CD4SP, 10 x 10(6) CD4SP, and 5 x 10(6) CD8SP did not established chimerism. CD8SP contained 44% of Ly6A/E (Stem Cell Antigen-1 (Sca-1))-positive cells based on FACS analysis, whereas only 6% of CD4SP were positive for Ly6A/E. MLR supernates of donor SPLCs chimeric mice using admixture with CD8SP dominated by Th2 cytokines. In contrast, mixting with MLR supernates from failed chimera showed dominant Th1 cytokines. CONCLUSIONS: CD8SP seems to make a major contribution to enhance BMC engraftment and induce donor-specific tolerance. Ly6A/E (Sca-1)-positive cells need to be further investigated for their contribution to the establishment of chimerism.

Hepatic clearance improves after angioplasty of the hepatic vein.

Anastomotic stricture sometimes causes hepatic congestion leading to decreased hepatic clearance of drugs. We herein describe a correlation between trough levels of tacrolimus and an anastomotic stricture of the hepatic vein. A 13-year-old boy underwent living donor liver transplant with a left lobe graft from his mother. Outflow blockage due to an anastomotic stricture of the hepatic vein developed 3 months after transplant. His anastomotic site had been repeatedly treated with percutaneous transvenous angioplasty (PTA) by balloon dilation. About 1 year after transplant, his trough level of tacrolimus promptly decreased after balloon dilation (from 15.7 to 5.6 ng/dL). Liver function tests showed abnormalities, which were diagnosed as acute cellular rejection, and he was treated with pulse steroid therapy. The calculated half-life of tacrolimus (T1/2) showed marked improvement after PTA (from 35 to 22 hours). A 45-year-old woman underwent living donor transplantation due to alcoholic liver cirrhosis with a left lobe graft from her brother. An anastomotic stricture of the hepatic vein developed 4 months after transplant. She was treated with balloon dilation, which caused an abrupt decrease in the trough level of tacrolimus (12 to 4 ng/dL). Her alkaline phosphatase was elevated and she was diagnosed with rejection, which was treated with an increase of dosage of tacrolimus. In outflow block, the T1/2 of tacrolimus increases probably due to decreased hepatic clearance by stagnation or congestion of the liver. However, hepatic clearance of drugs quickly recovers after PTA. Close monitoring of immunosuppressive agents is fundamental at the time of angioplasty to avoid acute cellular rejection as developed in our two cases.