Cardiac transplantation is the standard treatment for advanced cardiac failure, although this treatment is limited by shortage of the donor heart, preservation of the donor heart till transplantation, and immune response-relating rejection/infection/tumour. Of them, preservation of the donor heart has been substantially developed by an array of basic and clinical studies in the last 50 years. Cardiac preservation is targeting ischaemia-reperfusion injury that has been uncovered to be associated with immunological and infl ammatory reactions. It has been then revealed that the immunological and infl ammatory reactions as a result of ischaemia-reperfusion myocardial injury are closely associated with regeneration of the damaged cardiac tissue. This review documents historical and updated information regarding cardiac preservation and regeneration for treating advanced cardiac failure, and discusses future of cardiac regeneration therapy.
Because hydrogen provides potent antioxidative eff ects against acute lung injury, we hypothesized that treatment of organ donors with hydrogen during mechanical ventilation would reduce graft injury after lung transplant. Orthotopic left lung transplants were performed using an allogeneic rat model. Donors were exposed to mechanical ventilation with 98% oxygen plus 2% nitrogen or 2% hydrogen for 3 hours prior to harvest and the lung grafts underwent 4 hours of cold storage. The combination of mechanical ventilation and cold ischemia resulted in marked deterioration of gas exchange when the donors were ventilated with nitrogen, which was accompanied by upregulation of proinfl ammatory cytokines. These lung injuries were significantly attenuated by ventilation with hydrogen. Hydrogen induced heme oxygenase (HO)-1 in the grafts prior to implantation, which may contribute to protective eff ects aff orded by hydrogen. Hydrogen inhalation during ventilation prior to organ procurement eff ectively protected lung grafts from ischemia/reperfusion injury.
Human induced pluripotent stem cells (iPSCs) are pluripotent cell lines that can be established from somatic cells of any donor. Human iPSC-based cell/tissue transplantation has been regarded as one of their most attractive application. Although autologous iPSC-based cell therapy is preferable to avoid graft rejection, it would be fi nancially prohibitive to generate iPSCs for each individual. Therefore, it is necessary to consider allogeneic transplantation from human leukocyte antigen (HLA) -matched donors. In Japan, we have aimed to establish multiple clinical grade iPSC lines from donors that are homozygous for three HLA loci: HLA-A, -B and -DR, in order to establish an iPSC bank for medical use. Here I focus on the donor eligibility criteria and contents of the informed consent for the clinical iPS cell bank project in Japan.
Research resources bank of Ministry of Health and Labor was established in 1984. Our bank has accumulated a lot of know-how while providing research resources to many researchers. Especially with regard to the ethical handling on human-derived sample, is large role that public bank plays. Recently, we have been able to build a system that supplies in a refrigerated state, such as fresh human synovial tissue in Japan. Besides this, we are aggressively prepared to provide a sample prepared in the cells from the tissue. The future it can be expected that these know-how becomes the foundation for the regenerative medicine.
Recently, there is a growing need for human biospecimens in the fi eld of life science research. Therefore, many biobanks that collect and provide human specimens have been established worldwide. In Japan, several universities and hospitals have their own biobanks, but they are not being used much because of inadequate ethical guidelines and legal regulations. The Tsukuba Human Tissue Biobank Center (THB) was established in 2013 to provide a variety of tumor samples and their clinical data. It have been already collected a large number of specimens obtained from more than 2,000 patients. As a fi rst step, we could build the infrastructure for the biobank, and sample providing was started. Our next plan is to collaborate with other hospitals in the surrounding area. We hope the bionbank network support basis of research toward the achievement of regenerative medicine is build in the future.
The signifi cance of a public human tissue resource bank has been recognized for years in Japan. In this study, we attempted to establish a collection of various human cells from non-syndromic polydactyly tissue to donate the public tissue bank. Since the polydactyly operation is usually performed at around one-year old, informed consent was given by parents. So far, we have seven cases of donation and the recent three have a permission of donating public human resource bank. Considering researchers convenience, we aimed to supply isolated and cryopreserved cells, such as keratinocytes, fibroblasts, osteoblasts, preadipocytes, etc. Demands expected here were not only in the fi eld of basic biology, but broadly in development of drugs and cosmetics and regenerative medicine. To the author's knowledge, this is the fi rst collection of intact human skin- and bone-related materials to be available through a public research resource bank in Japan.
We have investigated the safety and efficacy of skeletal myoblast cell (SMBc) sheet transplantation for treating severe heart failure, in which scaffold-free cell-sheets are placed on the epicardial surface to maximize the paracrine eff ects. First-in-human clinical trial enrolled 4 DCM patients with LVAD, all of who successfully underwent transplantation of SMBc sheet without major complications, while 2 patients weaned off LVAD. The subsequent Phase I/IIa clinical trial enrolled 7 DCM patients and 8 ICM patients. As a result, symptoms, tolerance for exercise and incidence of heart failure were signifi cantly improved and cardiac function was recovered in the majority of the patients. SMBc sheet transplantation was feasible, safe and potentially effective to date and therefore further clinical follow-up and accumulation of the cases are required to establish the proof-of-concept of this treatment.
Hepatocyte transplantation (HT) is attractive option for urea cycle disorder and acute liver failure. HT has the benefit of non-invasive treatment, availability of hepatocyte isolated from marginal donors and cryopreserved hepatocytes at the time of need. On the other hand, the disadvantages of HT are injury of hepatocytes after thawing, difficulty of monitoring acute cellular rejection after HT, and limited donor source for HT. We experienced HT for neonatal ornithine transcarbamylase deficiency patient using hepatocytes from living donor for the fi rst case in the world. In our study, hepatocytes were isolated from the redundant liver of reduced left lateral segment graft from living donor. The quality of hepatocytes from living donor is better than that from deceased donor. The patient underwent living donor liver transplantation from his mother 5 months after HT.
Pancreatic islet transplantation has emerged as an eff ective treatment for type 1 diabetes patients with severe hypoglycemic unawareness. Islet transplants, though signifi cantly improving, are still mostly done on an experimental basis. We have started a phase-II clinical trial in type 1 diabetes mellitus patients for islet transplantation using donors after brain death and donors after cardiac death to evaluate a protocol involving induction of ATG and inhibition of TNF. Islet transplantation must be conducted under the new Regenerative Medicine Law in Japan, which went into eff ect in November 2014. The introduction of the regenerative medicine approach is expected to accelerate the development of islet transplantation. In this review, we outline a current status of islet transplantation and the future prospects.
Previously unknown histone H4 acetylation at Lysine 20 (H4K20ac) was intensively investigated. By mass spectrometry analysis, the existence of H4K20ac in mammalian cells was proved. The genome wide analysis by ChIP seq with a next generation sequencer revealed that H4K20ac was accumulated on the promoter region of weakly expressing genes, which is almost opposite to the conventional view of histone acetylation modifi cations. The motif search of H4K20ac suggested that well-known transcriptional repressor, NRSF can bind to H4K20ac distributed area. Furtherly, gene ontology identifi ed that H4K20ac was implicated in cell growth. New histone acetylation modifi cation, H4K20ac may open new mechanistic insight for cell growth.
In this study, to clarify the role of Kupff er cells (KCs) in the liver metastasis, we eliminated KCs at diff erent time points before or after injection of tumor cells (TCs). Our results suggested that the role of KCs was suppressive especially in the early stage of liver metastasis. In addition, we used intravital microscopy (IVM) to analyze the sinusoidal dynamics of both KCs and TCs in colon cancer metastasis to the liver. IVM showed that TCs adhered to KCs from the early time after TC injection. The KCs phagocytosed the TCs, which adhered with the KCs. It is suggested that KC phagocytosis of TCs in the early stage of liver metastasis strongly suppressed the formation of the liver metastatic nodules thereafter.
We herein showed the analysis of exosomes derived from cancer cells by nanobiodevices. At fi rst, the nano-pore device formed by an electrode couple on a nano-pore was developed. The number and size of exosomes could be analyzed by measuring the current value of the tunnel current of exosomes in the culture supernatant poured into nano-pore device. Next, the nano-wire device formed by nano-wires on a microfl uidic device made from polymethylmethacrylate (PMMA) was developed. The exosomes could be collected from the culture supernatant with high effi ciency by using this nano-wire device, and then miRNA existing in the exosomes could be extracted by pouring the miRNA extraction liquid into the nanowire device. In addition, these devices were available to the analysis of exosomes in the serum and urine. Therefore, the analysis of exosomes derived from cancer cells by nanobiodevices may be useful for the diagnosis of cancers in early stage.
The larger inter-individual variability of tacrolimus bioavailability is due to the CYP3A5 polymorphism and two oral formulations, twice-daily formulation (Prograf®, Astellas) and once-daily formulation (Graceptor®, Astellas), of tacrolimus. The median bioavailability of tacrolimus is significantly lower for recipients with the CYP3A5*1 allele than those with CYP3A5*3/*3 (12.6% vs. 19.3%, respectively for twicedaily and 9.1% vs. 15.4%, respectively for once-daily). In addition, the median bioavailability of tacrolimus in both genotypes is significantly lower in tacrolimus once-daily formulation than twice-daily. Costs of tacrolimus in recipients with CYP3A5*1 allele are 500,000-700,000 yen per one year higher than those with CYP3A5*3/*3. Furthermore, costs of tacrolimus in recipients with CYP3A5*1 allele taking twice-daily formulation are about 500,000 yen per one year lower than those taking once-daily formulation. Therefore, patients with CYP3A5*1 allele should be chosen twice-daily formulation, but not once-daily formulation, of tacrolimus. Knowledge of a patient’s CYP3A5 genotype before initiating tacrolimus therapy could be useful when making dosing decisions and formulation selection of tacrolimus. Pharmacogenomics for tacrolimus can adopt for pharmacoeconomics and is a new strategy that provides a method for a costeff ective therapy.
The second generation of mammalian target of rapamycin (mTOR) inhibitor everolimus has been applied as an immunosuppressive drug in patients receiving kidney transplantation as well as heart transplantation from December 2011 in Japan. Therapeutic drug monitoring (TDM) is required to adjust dosage in use of everoilmus as well as cyclosporine and tacrolimus in organ transplant patients. Recently, The Japanese Society of Therapeutic Drug Monitoring (JSTDM) has developed and launched the fi rst TDM guideline to standardize the routine TDM practice for immunosuppressive drugs (ISD) used in kidney, liver and heart transplantations. Toward the establishment of individualized dosage regimen of everolimus in organ transplant patients, periodic revision of the guideline would be required. In the present review, the recent development of everolimus TDM in the transplant patients has been summarized referring the first Japanese TDM guideline of immunosuppressive drugs.
Islet transplantation has been performed for the treatment of unstable type 1 diabetic patients. In year 2000, the University Alberta group demonstrated seven out of seven patients who received islet transplantations became insulin independence that triggered to spread clinical islet transplantation worldwide. In Japan, the Kyoto University group performed the first Japanese allogeneic islet transplantation in 2004 and the world first successful living donor islet transplantation in 2005. Since then, 18 allogeneic islet transplantations were performed using non-heart beating donors from 2004 to 2007. With advanced islet transplantation technologies, allogeneic islet transplantation became the standard therapy in the USA. Overcoming donor shortage is the next agenda and xenotransplantation using porcine islets is promising approach. In fact, clinical trial of porcine islet transplantation has been safely performed. Improving the efficacy of islet xenotransplantation is the current research target to become the standard therapy.
Islet transplantation has recently been shown to be successful in replacing pancreatic endocrine function into recipient with severe type 1 diabetes, but long-term insulin independence is usually not sustainable. We have previously reported that ex vivo Mitomycin-C treatment for islet graft prior to implantation induced a significant prolongation of islet graft survival in allograft and concordant xenograft transplantation model. Based on our experimental findings, prolongation of engraftment by sublethal genotoxic stress from MMC, without immune-suppressive agent, are characterized as 1) inhibition of cell death, 2) immune hyporesponsiveness at implantation site. This review will focus on our fi ndings about ex vivo MMC treatment for islet graft and the prospects based on the latest fi ndings.
We have previously shown that cytotoxicity of liver Natural Killer (NK) cells directed against allogeneic islets via TNF-related apoptosis-inducing ligand (TRAIL)-TRAIL receptor pathway early after intraportal islet transplantation. However, the mechanism of the activation of NK cells in early phase remains to be elucidated. It has been recently reported that the liver contain a certain amount of memory NK cells which express TRAIL and lack DX5. In this study, we demonstrated the activation of NK cells on the IBMIR (instant blood-mediated infl ammatory reaction) conditions and the expansion of liver DX5- memory NK cells in early phase after islet transplantation using a mouse model. Our data indicated that the liver-resident DX5- memory NK cells could powerfully and promptly respond against the transplanted islets even in syngeneic condition.
Primary graft dysfunction (PGD) is a morbid complication after heart transplantation (HTx). Preoperative inflammatory cytokine profi les of the recipients may be associated with a recipient’s propensity to have PGD. Serum samples were obtained from adult HTx recipients at 4 time points: (1) pre-reperfusion of transplanted hearts, (2) 1 hour-, (3) 3 hours-, and (4) 24 hours-after reperfusion. Major cytokines such as interleukin (IL)-6 and IL-8 were measured. Of 32 patients, 9 patients had PGD. Demographics and clinical data did not diff er between the groups. The patients having PGD had a higher baseline level of IL-8 than the patients without PGD. Within 3 hours after reperfusion, the patients with PGD had higher IL-6 and IL-8 levels. Higher infl ammatory status before and after transplant was found in HTx recipients who subsequently had PGD. That could represent a potential target for pretransplant pharmacological intervention.
After the tri-ministerial guideline for human genetic/genomic research (Ethics guidelines for human genome/genetic analytical research) was revised in 2013, the new ethical guideline (Ethical Guidelines for medical and health research involving human subjects) was introduced in 2014. Human genetic researchers have to refer these two ethical guidelines in their research activities. In this paper, the main points of these changes, especially concerning collections and distributions of human biological samples by a banking institution, are summarized.