When I started the research of lung preservation in 1975, clinical lung transplantation itself was not yet generalized clinically even in the western world. After starting the research, left lung preservations and transplantations were carried out week after week to clarify the optimum conditions using canine lung. Electrolyte composition and the colloid osmotic pressure of the solution, the mode of perfusion or ventilation were mainly examined in various combined manner. As a consequence, it was suggested that the replacement of pulmonary vasculature by the extracelluler type crystalloid solution having colloid osmosis with the positive airway inflation was the most appropriate condition for cold lung preservation based on research works continued more than 10 years. These results were verified again with the primate model of bilateral lung transplantation, and 25 years after starting the experiment, the preservation solution developed by vast series of experiments finally applied to the clinical lung transplantation in 2000.

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Liver transplantation is a standard treatment for serious liver failures and for liver based inborn errors of metabolism. However, shortage of livers is a major limiting factor and alternative solutions are expected in liver therapy. Cell transplantation using normal hepatocytes is awaited with great interest, but is still limited by limited cell proliferation and others. Hepatic stem/progenitor cells are activated in rodent models of liver regeneration after toxic injury. In humans, hepatic stem/progenitor cells may be activated and become enriched in different liver diseases such as chemical, viral hepatitis and cirrhosis. In this review, we describe isolation and differentiation of hepatic stem/ progenitor cells derived from human liver tissues with different liver diseases as a potential candidate for cell treatment in liver diseases.

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Carbon monoxide(CO)is produced endogenously as a byproduct of heme catalysis, and has been shown to provide protection against ischemia-reperfusion injury(IRI)in a variety of organs in murine models. Since CO is also known to be a toxic gas, translational research using large animals is essential prior to its use in the clinic. We have extensively studied the beneficial effects of CO inhalation using CLAWN miniature swine and reported that perioperative low-dose CO inhalation decreases lung IRI and that perioperative CO inhalation to both donor and recipient prolongs lung graft survival in MHC-inbred CLAWN miniature swine. To understand the mechanisms involved in prevention of graft damage following CO inhalation, we examined whether donor or recipient treatment alone is sufficient to prolong graft survival. 13 CLAWN swine received fully MHC mismatched lungs with 12 days of tacrolimus(days 0-11；35-45 ng/mL). In the control group(n＝6), recipients received tacrolimus alone. In D group(n＝4), only donor was treated with 200-250 ppm CO for 180 min. In R group(n＝3), 200-250 ppm CO was administered only to the recipient for 390 min until 2-hr reperfusion. All control recipients rejected the grafts by POD63. CO therapy only with donor(D group)was effective in prolonging graft survival. 3 out of 4 recipients accepted the grafts over 63 days. In contrast, all 3 recipients in R group rejected the grafts by POD63. These data suggest that donor CO alone is sufficient to improve lung graft survival in a clinically relevant large animal model.

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The organ function and its regulatory mechanisms which are affected by various physiopathological conditions have been analyzed by molecular and biochemical methods. We have been working on developing various optical probes to visualize cellular and organ conditions/functions in vivo. An innovative technology is essential for imaging the biological functions, especially by using bioluminescence；for example, a novel highly transmittable and sensitive optic probe. We have, so far, developed some novel probes based on the unique bioluminescence theories. By applying these probes for biological systems, we succeeded to visualize the dynamic changes of liver injury and oxidative stress in mouse liver ischemia/reperfusion model by the caspase-3 activity probe and redox sensitive GFP probe, respectively. These novel bio-imaging techniques will definitely bring great possibility and potential impact for research and clinical medicine in the future.

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Rejection is one of the major obstacles for the successful intestinal transplantation(ITx). In this study, we applied a new indocyanine green(ICG)fluorescence endoscope to a large animal ITx model. We performed swine heterotopic segmental ITx, and visualized mural vascular structure of the intestinal graft at various grade of acute rejection by the ICG fluorescence endoscope. The endoscopic findings revealed that the disarray and irregularity of the vascular structure worsened with increased grade of acute rejection. Clinical application of this new endoscopic evaluation for rejection in ITx is promising.

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As donor shortage is extremely severe in Japan because of very strict Organ Transplantation Law, special strategies for maximizing organ transplant opportunities should be established. Since November in 2002, special transplant management doctors were sent to donor hospitals in order to assess donorʼs organ function and to identify which organ could be transplanted. They also intensively cared the donor to stabilize hemodynamics and to improve cardiac and lung function by intravenously giving anti-diuretic hormone and pulmonary toileting by bronchofiberscopy. Organs procured from one donor increased from 4.5 to 5.6 after these strategies were applied. Patient survival rate at 10 years after each organ transplant was acceptable and comparable to that of other developed countries. Although the number of transplantation was still very small, the availability of organs has been very high and the outcomes of each organ transplantation were acceptable. These strategies may be useful to maximizing organ transplant opportunities.

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In Japan, the number of organ donation from cadaveric donors has been remarkably increased due to the revised organ transplant law which came into effect on July 17th, 2011. However provisions of suitable donor lung are still not enough to help all listed patients, resulting in long waiting time with a substantial risk of dying before lung transplantation. All measures to increase donation rates should be encouraged. Recently Japanese lung transplant teams have started active participation in donor management in order to improve donor lung utilization. A special consultant sent from lung transplant teams assesses donor lung function and involves in donor lung management for improvement of lung function. After the lung consultant system started, 33 out of 38 cadaveric donors(87%)served as lung donors. This percentage is much higher than that reported in the U. S., Canada, and Europe. This review updates current status of assessment and management of donor lungs, and discusses problems for maximizing the organ yield for lung transplantation in Japan.

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While revised Organ Transplant Act has been enforced and the number of organ donation from brain dead donors is increasing, the kidney donation after cardiac death (DCD) will be also performed as before. The recent results of cadaveric renal transplants using DCD kidneys in Japan are comparable to the results of selected centers in Europe and the United States. The in situ regional cooling technique using machine perfusion was developed to shorten warm ischemic time;this technique has been especially improved in our facilities. This review mentions the current status and prospects of donor evaluation and management for kidney transplantation from DCD.

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The number of deceased donor liver transplantation(DDLT)has dramatically increased after the revised Organ Transplant Law went into force on July 17, 2010. We experienced 12 cases of DDLT under the revised Organ Transplant Law. Four of twelve patients underwent DDLT for primary sclerosing cholangitis, for which it would be desirable to perform DDLT due to high recurrence rate after living donor LT from a relation in the first degree. The final evaluation of donor liver should be decided not by preoperative liver function but by intraoperative liver biopsy, since the criteria of extended criteria donor are not definitely determined except for severe macrovesicular steatosis. Six of twelve patients underwent split liver transplantation. To promote split liver transplantation is a useful way to increase the number of patients who can undergo DDLT.

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Results of intestinal transplantation(ITx)have been improving in recent years and ITx is now established as a therapeutic option for patients with severe intestinal failure. As of June 2012, 24ITxs have been performed for 21 patients in Japan. Twelve were deceased donor and 12 were living donor transplants. Fifteen of 21 patients are currently alive after ITx. Relatively few ITxs have been performed to date, mainly due to the lack of national insurance coverage for the procedure and shortage of the organ donation from pediatric cadaveric donors even after the revision of the Organ Transplant Law in Japan. This article reviews current status and future perspective in donor managements of clinical ITx on the basis of our experience and recent publications.

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Although organ cooling is beneficial for any kind of grafts, mainly by metabolic arrest, hypoxia and hypothermia concomitantly cause harmful reactions, such as ATP depletion, mitochondrial dysfunction, cytosolic Ca2＋ overload, intracellular acidosis, oxidative stress, cellular swelling, and cytoskeletal breakdown. To understand the optimal conditions of hypothermic oxygenated perfusion (HOPE), we reviewed the mechanisms of cold preservation injury, mainly focused on the mitochondrial function, cytosolic Ca2＋ overload, and downstream activation of proteases, phosphatases, and phospholipases. We also discussed the possibility of heavy water(deuterium water)containing buffers for the use of a perfusate in HOPE.

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Brain-dead donors and living lower lobe donors are utilized for clinical lung transplantation in Japan. But it is limited by the availability of the donors because of medical and cultural hurdles. To expand the donor source, we performed lung transplantation from non-heart beating(NHB)donors after brain death in animal experimental models in the 1990s. We succeeded left lung transplantation from NHB donor in a canine model and bilateral lung transplantation from NHB donor in a primate model. It is concluded that the NHB donor after brain death is available for lung transplantation but some medical, social and cultural issues should be still resolved to utilize NHB donors for clinical lung transplantation in Japan.

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The shortage of organ donors is a serious worldwide problem. Donation after cardiac death may contribute to the expansion of donor pool. However, the use of these marginal grafts requires the development of the preservation methods because of higher risks of primary non-functioning and severe ischemic reperfusion injury. Recently, normothermic preservation has been attracting attention to resusciate suboptimal grafts. Porcine livers were perfused with our own machine perfusion system(MPS). A donor liver suffering from 60 min-warm ischemiawas perfused to flush out blood with Euro-Collins containing of urokinase and phentolamine mesilate. Then, the liver was perfused continuously for 60 min with UW-gluconate plus low molecular dextran and amino acids. Orthotopic liver transplantation was carried out in pig recipient. As for preservation condition, there were three groups；Group 1：grafts were perfused at 8℃by MPS. Group 2：grafts were perfused at 25℃by MPS. Group 3：grafts were perfused with rewarming from 4℃to 25℃during preservation by MPS. Recipient serum AST, LDH 2 hrs after reperfusion were significantly lower in Group 3 compared with Group 1. Pathologically, intralobular hemorrhage was less severe in Group 3 than in Group 1. These results indicates our MPS preservation may resuscitate injured graft liver and rewarming during preservation may be effective as a graft conditioning to prevent ischemic reperfusion injury, particularly for the donation after cardiac death liver grafts.

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In spite of increasing donation from the brain dead(BD)donors, the non-heart beating(NHB) donor is still main source of kidney transplantation in Japan. In our facilities 45 cases of kidney transplantation from the NHB donors and 17 cases from the BD donors have been performed since 2004. The delayed graft function rate was higher on NHB donor transplants than in BD donor kidneys(97.3％ vs. 41.2％). Graft function estimated by serum creatinine levels at 1, 3, 6, 12 months was significantly better in the BD donor group. In our study graft function was better in the BD donor group. However, many kidneys from the NHB donors were functioning well. Therefore, NHB donors still should be considered as a viable source of kidneys for transplantation.

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The wide gap between the numbers of patients on the waiting list for pancreas transplantation and the insufficient numbers of organ donors results in the use of critical donors, so-called marginal donors or extended criteria donors(ECD). Thirty two pancreas transplantations were performed in our institute between 1991 and 2012 from 11 non-heart beating donors and 21 brain-dead donors. They were evaluated for the conventional criteria concerning ECD previously advocated and new criteria which we have recently proposed. If according to the conventional criteria, most of the brain-dead donors were excluded from the application of pancreas transplantation, however they actually developed excellent primary organ function. It appears that conventional criteria for ECD are too restrictive and our criteria fit into the reality of Japan.

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Pharmacogenetic information in the package insert was reviewed. Most of the information was gene polymorphisms for the drug metabolizing enzymes such as cytochrome-P450 (CYP) and UDP-glucuronyl transferase(UGT), which alter the pharmacokinetics for substrate drugs resulting in individual variation of drug response including efficacy and adverse effects. In the typical substrates for these enzymes (proton pump inhibitors, clopidogrel, irinotecan and warfarin), difference in the pharmacological efficacy and side effects are discussed among the patients groups carrying different genotypes. HLA types identified for drug-induced serious dermatitis and hypersensitivity for abacavir, carbanazepine and alloprinol are also included in this review.

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There is no consensus on therapeutic drug monitoring(TDM)of vancomycin in pediatric patients. IDSA, ASHP and SIDP published a consensus review of TDM of vancomycin in adult patients. Based on the consensus review, I will comment on the indication to vancomycin monitoring in pediatric patients. Serum vancomycin trough concentration above 10 mg/L is recommended to avoid development of resistance, and the trough concentration would have to be 15-20 mg/L to generate the target AUC/MIC≧400 for a pathogen with an MIC of 1mg/L in adult. However, the Japanese Society of Chemotherapy recommended primary target trough concentrations of 10-15 mg/L in order to avoid nephrotoxicity. We conducted simulation of optimal trough concentration to obtain AUC/MIC≧400 by Monte-Carlo method. The result of simulation and much information indicated that in Japanese pediatric patients, recommended trough concentrations for not complicated infections are primarily 10-1 5 mg/L then consider 15-20 mg/L. The dose of 20 mg/kg(as an actual body weight)given every 8 hr is recommended for most pediatric patients with a normal renal function.

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Use of generic drugs is recommended because of their economic advantage. However, bland and generic drugs have never been compared from the view point of their pharmacological efficacy by lymphocyte immunosuppressant-sensitivity test(LIST)with 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide(MTT)assay procedure. In this study, we evaluated the pharmacological efficacy of the bland and its generic drugs of methylprednisolone sodium succinate by LIST using peripheral blood mono nuclear cells (PBMCs) obtained from one healthy volunteer. The results showed wide difference of 90％ confidence interval between IC50 logarithmic value； however, there were no statistically significant difference in IC50 logarithmic values between these drugs. We concluded from these data that immunosuppressive pharmacological efficacy of these generic methylprednisolone sodium succinate was almost equivalent to that of the bland drug. However, further investigation is recommended to evaluate and confirm the pharmacological and economic advantage between bland and generic drugs by LIST.

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[in Japanese]

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