Atsuyoshi Mita

Long-term results of living-related donor liver graft transplantation: a single-center analysis of 110 transplants.

BACKGROUND Difficulties of cadaveric donation and serious donor shortage have led to the development and popularization of living-related donor liver graft transplantation (LRLT). Because the history of this procedure is rather short, important aspects specific to this procedure have not been sufficiently documented. The objective of this study was to analyze a single centers 10-year experience with 110 LRLT in pediatric and adult patients with end-stage liver diseases. METHODS The medical records of 110 consecutive patients who underwent LRLT were reviewed. The recipients were comprised of 72 children and 38 adults. The graft volume corresponded to 26-192% of the recipients standard liver volume. The relationship between pretransplant covariates and patient and graft survival was analyzed. Actuarial patient/graft survival rates were determined at 1, 3, and 5 years. The type and incidence of posttransplant complications were analyzed, as was long-term graft function. RESULTS The 1-, 3-, and 5-year actuarial patient and graft survival rates were 88%, 85%, and 85%, respectively. Log-rank test demonstrated that ABO-compatibility predicted patient survival rate, whereas patient age, underlying disease, patients clinical status, donor-recipient relation, donor age, and graft volume/standard liver volume ratio did not. Long-term liver function remains excellent. All the donors have returned to normal daily lives with an uneventful course. CONCLUSIONS LRLT is an efficacious procedure that provides excellent short-term and long-term survival. The indication criteria for both recipient and donor were legitimate in this series, except for transplant across ABO-incompatibility. Cautious expansion of this procedure may be justified under the situation of serious shortage of cadaveric donor.

Living liver donation: preoperative assessment, anatomic considerations, and long-term outcome1

Background. A major prerequisite for living donor liver transplantation (LDLT) as an acceptable treatment modality is thoughtful consideration of the donor. However, there has been no comprehensive audit of living liver donation focusing on issues such as donor selection, anatomic surveys, and long-term outcome. Methods. Between June 1990 and January 2002 at our institution, 160 LDLTs were performed and 177 patients were referred for LDLT. For these patients, a total of 203 potential donors were screened. The process of donor selection, safety of donor hepatectomy, and postoperative morbidity were investigated. Additionally, an anonymous questionnaire was administered to 100 donors who had undergone LDLT more than 3 years previously. Results. Thirty-eight (19%) of the 203 donor candidates were excluded. Precise estimation of the hepatic anatomy was indispensable for donor safety. None of the donors showed prolonged postoperative liver dysfunction nor developed complications requiring reoperation or readmission. There was no donor mortality. The responses to the questionnaire indicated that 95% of the living donors had not felt coerced to donate and that 5% were neutral about coercion pressure. There were no severe postoperative aftereffects, but minor problems were reported by 51% of the respondents. Conclusions. Our appraisal of the perioperative and long-term postoperative course of LDLT donors revealed that although most donors are satisfied after undergoing LDLT, there is a need for strict attention to the process of donor selection and long-term postoperative follow-up. The outcome of the present series seems to confirm the safety of donor hepatectomy.

Expression of Fas Ligand by Hepatic Macrophages in Patients with Fulminant Hepatic Failure

OBJECTIVES:The mechanisms of Fas–Fas ligand (Fas–FasL)-mediated apoptosis in the pathogenesis of fulminant hepatic failure (FHF) have not been well defined. This clinical study was carried out to assess which cells expressed Fas–FasL and to determine their involvement.METHODS:The subjects were 24 patients with FHF who underwent liver transplantation at our institution. For comparison, nine chronic hepatitis (CH) patients and six living liver donors (LD) were also enrolled. Liver tissues were obtained for histological (hematoxylin–eosin, terminal deoxynucleotidyl transferase [TdT]-mediated dUTP-biotin nick-end labeling [TUNEL], immunohistochemistry, and double immunofluorescence staining) and reverse transcription PCR (RT-PCR; cytokines and chemokines) analysis.RESULTS:The numbers of TUNEL-, FasL-, and CD68-positive cells in the livers of patients with FHF were significantly larger than in those with CH or with normal livers. Double immunofluorescence staining showed that FasL was expressed predominantly on liver macrophages and rarely on CD8-positive lymphocytes. RT-PCR study showed increased expression of FasL; interferon-γ; interleukin-18; macrophage inhibitory protein-1β; and regulated upon activation, normal T cell expressed and secreted in the livers of patients with FHF compared with those of LD.CONCLUSIONS:Macrophages and their expression of FasL may play roles in the pathogenesis of FHF.

Characterization of pancreatic ductal cells in human islet preparations

Substantial amounts of nonendocrine cells are implanted as part of human islet grafts, and a possible influence of nonendocrine cells on clinical islet transplantation outcome has been postulated. There are currently no product release criteria specific for nonendocrine cells due to lack of available methods. The aims of this study were to develop a method for the evaluation of pancreatic ductal cells (PDCs) for clinical islet transplantation and to characterize them regarding phenotype, viability, and function. We assessed 161 human islet preparations using laser scanning cytometry (LSC/iCys) for phenotypic analysis of nonendocrine cells and flow cytometry (FACS) for PDC viability. PDC and β-cells obtained from different density fractions during the islet cell purification were compared in terms of viability. Furthermore, we examined PDC ability to produce proinflammatory cytokines/chemokines, vascular endothelial growth factor (VEGF) and tissue factor (TF) relevant to islet graft outcome. Phenotypic analysis by LSC/iCys indicated that single staining for CK19 or CA19-9 was not enough for identifying PDCs, and that double staining for amylase and CK19 or CA19-9 allowed for quantitative evaluation of acinar cells and PDC content in human islet preparation. PDC showed a significantly higher viability than β-cells (PDC vs β-cell: 75.5±13.9 and 62.7±18.7%; P<0.0001). Although β-cell viability was independent of its density, that of PDCs was higher as the density from which they were recovered increased. There was no correlation between PDCs and β-cell viability (R2=0.0078). PDCs sorted from high-density fractions produced significantly higher amounts of proinflammatory mediators and VEGF, but not TF. We conclude that PDCs isolated from different fractions had different viability and functions. The precise characterization and assessment of these cells in addition to β-cells in human islet cell products may be of assistance in understanding their contribution to islet engraftment and in developing strategies to enhance islet graft function.

An alternative method of arterial reconstruction after hepatic arterial thrombosis following living-related liver transplantation.

BACKGROUND Hepatic artery thrombosis (HAT) remains an important cause of graft loss after liver transplantation. Emergency rearterialization methods are limited in cases of living-related liver transplantation in which the graft hepatic artery is thin and short. CASE A 19-year-old woman who underwent living-related liver transplantation for biliary atresia developed HAT on the 4th postoperative day. During the emergency laparotomy the recipient hepatic artery was found to be too short to anastomose, so the recipients right gastroepiploic artery was anastomosed to the graft hepatic artery. The patient is now alive and well 6 months after reoperation, and she has experienced no further episode of HAT. CONCLUSION The right gastroepiploic artery can be used easily and safely for hepatic graft revascularization without causing ischemia of the stomach. An additional skin incision is not required, and the artery is long enough to anastomose to the graft artery directly. The method of hepatic graft rearterialization described here is an important option for patients who undergo living-related or split liver transplantation.

Prolactin Supplementation to Culture Medium Improves β-cell Survival

Objectives. Recent studies demonstrated that prolactin (PRL) has beneficial effects on &bgr; cells for islet transplantation. We examined the effect of human recombinant PRL (rhPRL) supplementation to the culture media to determine its potential use in the context of clinical islet transplantation. Materials and Methods. Each human islet isolated from 14 deceased multiorgan donors was cultured in Miami modified media-1 supplemented with or without rhPRL (500 &mgr;g/L) for 48 hr. &bgr;-Cell survival and proliferation (BrdU and Ki-67) were determined by laser scanning cytometry. The cytoprotective effects of rhPRL against noxious stimuli were assessed by flow cytometry (tetramethylrhodamine ethyl ester). Cytokine/chemokine and tissue factor productions were measured in vitro, and islet potency was assessed in vivo in diabetic immunodeficient mice. Results. &bgr;-Cell survival during culture was 37% higher in the rhPRL group than in control (P=0.029). rhPRL protected &bgr; cells in vitro from cytokines, Nitric oxide donor, and H2O2. The exposure to rhPRL did not affect human &bgr;-cell proliferation with our protocol. rhPRL treatment did not alter cytokine/chemokine and tissue factor production in vitro or affected human islet functionality in vivo: recipient mice achieved normoglycemia with a comparable tempo, whereas loss of graft function was observed in two of the seven mice in the control group and in none of the rhPRL group (p=n.s.). Conclusion. rhPRL supplementation to islet culture media improved human &bgr;-cell-specific survival without altering islet quality. Addition of rhPRL to cultured islets may grant a more viable &bgr;-cell mass in culture. The development of &bgr;-cell cytoprotective strategies will be of assistance in improving islet transplantation outcomes.

Antiproinflammatory effects of iodixanol (OptiPrep)-based density gradient purification on human islet preparations.

Islet isolation and purification using a continuous density gradient may reduce the volume of tissue necessary for implantation into patients, therefore minimizing the risks associated with intraportal infusion in islet transplantation. On the other hand, the purification procedure might result in a decreased number of islets recovered due to various stresses such as exposure to cytokine/chemokine. While a Ficoll-based density gradient has been widely used in purification for clinical trials, purification with iodixanol (OptiPrep) has been recently reported in islet transplant series with successful clinical outcomes. The aim of the current study was to compare the effects of the purification method using OptiPrep-based and Ficoll-based density gradients. Human islet isolations were performed using a modified automated method. After the digestion phase, prepurification digests were divided into two groups and purified using a semiautomated cell processor with either a continuous Ficoll- or OptiPrep-based density gradient. The quantity, purity, viability, and cellular composition of islet preparations from each group were assessed. Cytokine/chemokine and tissue factor production from islet preparations after 48-h culture were also measured. Although islet purity, postpurification IEQ, islet recovery rate, FDA/PI, and fractional β-cell viability were comparable, β-cell mass after 48-h culture significantly improved in the OptiPrep group when compared to the Ficoll group. The production of cytokine/chemokine including IL-1β, TNF-α, IFN-γ, IL-6, IL-8, MIP-1β, MCP-1, and RANTES but not tissue factor from the OptiPrep group was significantly lower during 48-h culture after isolation. Each preparation contained the similar number of ductal cells and macrophages. Endotoxin level in both gradient medium was also comparable. The purification method using OptiPrep gradient media significantly reduced cytokine/chemokine production but not tissue factor from human islet preparations and improved β-cell survival during pretransplant culture. Our results suggest that the purification method using OptiPrep gradient media may be of assistance in increasing successful islet transplantation.

Nonsurgical policy for treatment of bilioenteric anastomotic stricture after living donor liver transplantation

Biliary complications remain a significant cause of morbidity following living donor liver transplantation. The purpose of this retrospective study was to assess the outcome of nonsurgical management for hepatojejunostomy stricture in our institution. We reviewed 22 patients with hepatojejunostomy stricture among the 231 patients who underwent living donor liver transplantation between June 1990 and December 2005. Hepatojejunostomy stricture was confirmed by percutaneous transhepatic or endoscopic retrograde cholangiography. Anastomotic strictures were treated by balloon dilatation. Percutaneous transhepatic cholangiography was performed on 15 of the 22 patients. Two of 15 patients, with complete obstruction of the anastomosis, were treated successfully by Yamanouchi magnet compression anastomosis. Although another two patients died of infectious disease that was unlikely to have been related to biliary complications, anastomotic patency was maintained in the other 13 patients. Endoscopic retrograde cholangiography was performed on seven of the 22 patients. None of the 22 patients required re‐operation or died of biliary complications. The 5‐year graft survival rate of 85.6% in the 22 patients with stricture was equivalent to that of the patients without stricture (82.9%, P = 0.98). Advances in intervention techniques have enabled wider application of nonsurgical approaches for this complication, and fair results have been obtained.

Anti-proinflammatory effects of sirolimus on human islet preparations

Background. Sirolimus plays a critical role in facilitating steroid-free immunosuppression, in conjunction with low dose tacrolimus, in current islet transplantation. Although several studies have investigated the effects of sirolimus on islet cells, conflicting results have been reported. In this study, we assessed the effects of sirolimus supplementation in culture media on human islet preparations, focusing on the anti-proinflammatory aspects. Methods. Human islet preparations were divided into four groups: pure (purity >90%) sirolimus (30 ng/mL); pure control (0 ng/mL); impure (purity 40%–60%) sirolimus; and impure control. All groups were cultured for 3 days and assessed regarding glucose stimulated insulin release, fractional β-cell viability, β-cell, and macrophage content. Cytokine and chemokine production from islet preparations and sorted pancreatic ductal cells were also examined. Results. Stimulated insulin release in the impure sirolimus group was significantly increased (P=0.024), as previously reported. Although fractional β-cell viability showed no significant differences, β-cell survival during culture significantly increased in impure sirolimus group when compared with the impure control group (P=0.015). Tumor necrosis factor-α, interleukin-1β, monocyte chemotactic protein-1, and macrophage inflammatory protein-1β production from the impure sirolimus group significantly decreased (P<0.05). Furthermore, tumor necrosis factor-α and macrophage inflammatory protein-1β production from sorted ductal cells significantly decreased in the sirolimus group (P<0.05). The number of macrophages contained in islet preparations significantly decreased in the impure sirolimus group when compared with the impure control group (P<0.05). Conclusions. Sirolimus improved not only stimulated insulin release, but also β-cell survival during culture. The antiinflammatory effects of sirolimus also appear beneficial to islet cells in culture and may be a useful strategy in improving islet transplantation outcomes.

Life-threatening veno-occlusive disease after living-related liver transplantation.

Veno-occlusive disease (VOD) can develop in association with the administration of cytotoxic chemotherapeutic agents and irradiation. In solid-organ transplant settings, azathioprine has been implicated as a predisposing factor. VOD with fatal outcome occurred in a post liver-transplant recipient who had never been exposed to any agents that have the potential to induce VOD. At onset, the disease manifested clinically as gross ascites and progressive jaundice and was observed after clinically diagnosed acute graft rejection. The disease was confirmed by histologic examinations. Histologic studies of biopsy samples from this patient revealed that most small hepatic veins less than 300 microm in diameter were affected, exhibiting concentric intimal thickening with sparse inflammatory cells. A few of the hepatic veins exhibited active endotheliitis with occasional extension of inflammation to neighboring centrilobular areas. Despite intensified immunosuppression, the observed fibrous obliterative changes were irreversible. Although the cause of VOD in this patient is tentative, the damage to the endothelium, associated with acute rejection, is likely to be attributable. VOD deserves recognition as one of the causes for liver dysfunction and persistent ascites after liver transplantation.