Adverse events related to platelet-rich plasma therapy and future issues to be resolved.

Platelet-rich plasma (PRP) is the portion of plasma with a platelet concentration above baseline that is recovered through centrifugation of autologous blood. PRP therapy is currently used for wound healing and pain relief in diverse medical fields. Although there have been recent reports of adverse events (AEs) possibly related to PRP treatment, the safety profile of PRP treatment remains unclear. Therefore, this review discusses the risks inherent in PRP therapy and the current issues by surveying reports on AEs associated with PRP treatment within different fields. PubMed was searched for research articles referring to AEs associated with PRP therapy from inception to January 2024. Literature survey revealed that PRP therapy may involve several AEs, including postoperative infections, blindness, inflammation, allergic reactions, and nodule development. The most commonly reported AE was postoperative infections. Since PRP therapy generally proceeds in the process of blood collection, manufacturing, and administration to patients, it is conjectured that PRP may have been contaminated with microorganisms at some point in this series of processes, leading to bacterial infection. Additionally, because PRP cannot be sterilized like pharmaceuticals, it is important to prevent microbial contamination during each PRP treatment process. However, the specific process that involves the risk of microbial contamination remains unclear. To take measures to prevent microbial contamination of PRP, it may be necessary to elucidate the risk factors for microbial contamination during PRP treatment. It may be important to elucidate the effectiveness and risks of PRP therapy as well as to establish a follow-up system after PRP treatment. Currently, most reports of AEs related to PRP therapy are case reports; therefore, the accumulation of high-quality evidence and detailed verification are necessary to determine the causal relationship between PRP therapy and each AE.

Interleukin-10 induces TNF-driven apoptosis and ROS production in salivary gland cancer cells.

Treatment resistance after chemo-/immunotherapy occurs in patients with head and neck squamous cell cancers (HNSCs), including salivary gland cancers (SGCs). Interleukin-10 (IL-10), a cytokine with pro- and anti-cancer effects, has an unclear impact on HNSC/SGC cells. We show that HNSC patients exhibiting high expression of IL-10 and its receptor IL-10Rα experience have prolonged overall survival. Immunoreactive IL-10 was low in ductal cells of human SGC biopsies. Human (A253) and murine WR21-SGC cells expressed IL-10Rß, but only A253 cells expressed IL-10 and IL-10Rα. The addition of recombinant IL-10 impaired SGC cell proliferation and induced apoptosis in vitro. N-acetylcysteine restored IL-10-induced reactive oxygen species (ROS) production but did not prevent IL-10-mediated viability loss. Mechanistically, recIL-10 delayed cell cycle progression from G0/G1 to the S phase with cyclin D downregulation and upregulation of NF-kB. IL-10 increased tumor necrosis factor-α (TNF-α) in A253 and WR21 and FasL in WR21 cells. Neutralizing antibodies against TNF-α and NF-kB inhibition restored SGC proliferation after IL-10 treatment, emphasizing the critical role of TNF-α and NF-kB in IL-10-mediated anti-tumor effects. These findings underscore the potential of IL-10 to impede SGC cell growth through apoptosis induction, unraveling potential therapeutic targets for intervention in salivary gland carcinomas.

Identification of risk factors for the onset of delirium associated with COVID-19 by mining nursing records.

COVID-19 has a range of complications, from no symptoms to severe pneumonia. It can also affect multiple organs including the nervous system. COVID-19 affects the brain, leading to neurological symptoms such as delirium. Delirium, a sudden change in consciousness, can increase the risk of death and prolong the hospital stay. However, research on delirium prediction in patients with COVID-19 is insufficient. This study aimed to identify new risk factors that could predict the onset of delirium in patients with COVID-19 using machine learning (ML) applied to nursing records. This retrospective cohort study used natural language processing and ML to develop a model for classifying the nursing records of patients with delirium. We extracted the features of each word from the model and grouped similar words. To evaluate the usefulness of word groups in predicting the occurrence of delirium in patients with COVID-19, we analyzed the temporal changes in the frequency of occurrence of these word groups before and after the onset of delirium. Moreover, the sensitivity, specificity, and odds ratios were calculated. We identified (1) elimination-related behaviors and conditions and (2) abnormal patient behavior and conditions as risk factors for delirium. Group 1 had the highest sensitivity (0.603), whereas group 2 had the highest specificity and odds ratio (0.938 and 6.903, respectively). These results suggest that these parameters may be useful in predicting delirium in these patients. The risk factors for COVID-19-associated delirium identified in this study were more specific but less sensitive than the ICDSC (Intensive Care Delirium Screening Checklist) and CAM-ICU (Confusion Assessment Method for the Intensive Care Unit). However, they are superior to the ICDSC and CAM-ICU because they can predict delirium without medical staff and at no cost.

Current status of platelet-rich plasma therapy under the act on the safety of regenerative medicine in Japan.

In Japan, a legal framework has been established for the safe and effective application of regenerative medicine. After eight years of the Act on the Safety of Regenerative Medicine (RM Act), discussions have been underway in the Ministry of Health, Labor and Welfare of Japan to revise the law owing to numerous novel technologies and inappropriate case reports not anticipated when the law was enacted. Therefore, in this review article, we have reviewed the regenerative medicine provision plans and the contribution of platelet-rich plasma (PRP) therapy, a regenerative medicine technique widely used in Japan post RM Act implementation, to these plans. As of January 2022, 97.2% of the regenerative medicine provided under the RM Act had been for private practice, and most of them were Class Ⅲ regenerative medicine. Notably, PRP was the most used processed cell under the RM Act. PRP therapy accounted for approximately 66% of the regenerative medicine provision plans in clinical research or private practice and was the most provided regenerative medicine technology in Japan. PRP therapy was primarily used in dentistry to regenerate periodontal tissue (approximately 50%), followed by orthopedics, where it is used to treat osteoarthritis. We suggest that further discussion is essential to determine the factors that should be addressed by the RM act to evaluate the efficacy and safety of PRP therapy.

The Role of the Plasminogen/Plasmin System in Inflammation of the Oral Cavity.

The oral cavity is a unique environment that consists of teeth surrounded by periodontal tissues, oral mucosae with minor salivary glands, and terminal parts of major salivary glands that open into the oral cavity. The cavity is constantly exposed to viral and microbial pathogens. Recent studies indicate that components of the plasminogen (Plg)/plasmin (Pm) system are expressed in tissues of the oral cavity, such as the salivary gland, and contribute to microbial infection and inflammation, such as periodontitis. The Plg/Pm system fulfills two major functions: (a) the destruction of fibrin deposits in the bloodstream or damaged tissues, a process called fibrinolysis, and (b) non-fibrinolytic actions that include the proteolytic modulation of proteins. One can observe both functions during inflammation. The virus that causes the coronavirus disease 2019 (COVID-19) exploits the fibrinolytic and non-fibrinolytic functions of the Plg/Pm system in the oral cavity. During COVID-19, well-established coagulopathy with the development of microthrombi requires constant activation of the fibrinolytic function. Furthermore, viral entry is modulated by receptors such as TMPRSS2, which is necessary in the oral cavity, leading to a derailed immune response that peaks in cytokine storm syndrome. This paper outlines the significance of the Plg/Pm system for infectious and inflammatory diseases that start in the oral cavity.

Difficulties in ensuring review quality performed by committees under the Act on the Safety of Regenerative Medicine in Japan.

We outlined five studies regarding the quality of the review by committees based on the Act on the Safety of Regenerative Medicine. The findings raise serious concerns about the independence, integrity, and quality of reviews of therapeutic plans by these committees with inappropriately close relationships to medical institutions and companies.

Clinical Research on the Safety Evaluation of Platelet-rich Plasma Treatment in Oral Diseases: A Study Protocol.

Background: Platelet-rich plasma (PRP) is a biological product obtained from autologous blood that contains growth factors, promoting the healing and regeneration of human tissues. Several oral diseases require surgical intervention, producing residual wounds that undergo a healing process, accompanied by pain, swelling, superinfections, and bone remodeling. This protocol study aims to evaluate the safety of PRP use for the following dental procedures: post-extraction socket healing, periodontal tissue regeneration, maxillary sinus floor elevation, tooth transplantation, and intentional tooth replantation. Methods: Ten patients will be enrolled and subjected to the required treatment with the addition of PRP, after appropriate hematological and biochemical evaluations. The participants will then be subjected to an observation period of 4 weeks to monitor adverse events through clinical observation. Secondary outcomes will regard pain, and clinical evolution of the treated site. Among these, presence of infection, swelling, wound healing, stability of the transplanted tooth. Discussion: Safety of medical procedures represents the first requirement for their introduction in routine practice. A careful evaluation of clinical response during follow-up period and registration of adverse effects is fundamental for safety confirmation and subsequent use of PRP for the proposed dental procedures. Trial registration: Japan Registry of Clinical Trials (https://jrct.niph.go.jp/, registry number: jRCTc030190273, jRCTc030190274, jRCTc030190275, jRCTc030190276, jRCTc030190277; Date of registration: 31 March 2020).

The stem cell transcription factor ZFP296 transforms NIH3T3 cells and promotes anchorage-independent growth of cancer cells.

Cancer cells and embryonic stem (ES) cells share several biological properties, suggesting that some genes expressed in ES cells may play an important role in cancer cell growth. In this study, we investigated the possible role of zinc finger protein 296 (ZFP296), a transcription factor expressed in ES cells, in cancer development. First, we found that overexpression of Zfp296 in NIH3T3 mouse fibroblasts induced two phenomena indicative of cell transformation: enhanced proliferation under low-serum conditions and anchorage-independent growth. We also found that Zfp296 expression was upregulated in the tumor area of a mouse model of colon carcinogenesis. In addition, the expression levels of ZFP296 in various human cell lines were generally low in normal cells and relatively high in cancer cells. Finally, using a soft agar assay, we found that overexpression of ZFP296 promoted the anchorage-independent growth of cancer cells, while its knockdown had the opposite effect. Overall, these results suggest a possible role of the ES-specific transcription factor ZFP296 in cancer.

Study protocol for periodontal tissue regeneration with a mixture of autologous adipose-derived stem cells and platelet rich plasma: A multicenter, randomized, open-label clinical trial.

Introduction: Adipose-derived stem cells (ASCs) secrete various growth factors to promote wound healing and to regenerate various tissues, such as bone, cartilage, and fat tissue. Subcutaneous adipose tissue is a considerable cell source in clinical practice and can be collected relatively easily and safely under local anesthesia. Moreover, platelet-rich plasma (PRP), a plasma component containing many platelets purified by centrifuging the collected blood, also promotes wound healing. PRP can be easily gelled and is therefore attracting attention as a scaffolding material for transplanted cells. The usefulness of a mixture of ASCs and PRP for periodontal tissue regeneration has been in vitro demonstrated in our previous study. The aim of this study is to present the protocol of translation of tissue regeneration with ASCs and PRP into practical use, evaluating its efficacy. Methods: This study is a multicenter, randomized, open-label comparative clinical trial. Fifteen patients will be randomly assigned to the treatment with mixture of ASCs and PRP or enamel matrix derivate administration into periodontal tissue defects. Increase in height of new alveolar bone in the transplanted area will be evaluated. The evaluation will be performed using dental radiographs after 36 weeks of transplantation. Occurrence of adverse events will be evaluated as secondary outcome. Results: This clinical study was initiated after meeting the regulations to be complied with, including ethical review and regulatory notifications. Conclusions: If effective, this cell therapy using autologous mesenchymal stem cells can represent a useful medical technology for regeneration of periodontal defects.

Reactogenicity and immunogenicity of BNT162b2 or mRNA-1273 COVID-19 booster vaccinations after two doses of BNT162b2 among healthcare workers in Japan: a prospective observational study.

BACKGROUND: This study evaluates the immunogenicity and reactogenicity of BNT162b2 and mRNA-1273 booster doses after the primary two-dose BNT162b2 series in Japan and is the first report from Western Pacific region. RESEARCH DESIGN AND METHODS: Healthcare workers receiving the two-dose BNT162b2 series and eligible for booster vaccination were enrolled. Self-reported adverse reactions were recorded for 8 days. Antibody titer was measured at baseline and on day 28. RESULTS: A total of 2,931 and 890 subjects received BNT162b2 (homologous) and mRNA-1273 (heterologous) booster vaccinations, respectively. The anti-SARS-CoV-2 spike protein IgG titer increased by 50.9- and 64.3-fold in the homologous and heterologous groups, respectively. Immunogenicity was greater with increasing age, regardless of sex. Adverse reactions were mild to moderate and decreased with age. The most common adverse reactions were injection-site pain (92.2%), fatigue (71.8%), headache (58.3%), and fever ≥37.5°C (46.5%). Two cases of non-severe myocarditis occurred in the heterologous group and resolved without clinical sequelae. CONCLUSION: Homologous booster schedules had fewer reported adverse reactions; heterologous boosters elicited greater immunogenicity. Among different age groups, subjects aged 60 or over had the lowest immunogenicity before the booster, and both homologous and heterologous boosters restored vaccine immunogenicity level comparable to those of younger age groups.

Bone Regeneration with a Combination of Adipose-Derived Stem Cells and Platelet-Rich Plasma.

Mesenchymal stem cells (MSCs) have the potential to directly differentiate into osteogenic cells and efficiently regenerate bone tissue. Adipose-derived stem cells (ASCs) have the potential to differentiate into an osteogenic lineage, too. In addition, ASCs can be readily harvested in large numbers with low donor-site morbidity. Meanwhile, recent reports have demonstrated that platelet-rich plasma (PRP) contains a variety of growth factors and may be a powerful biological autologous cocktail of growth factors for tissue engineering.We have shown that ASC/PRP admixture had dramatic effects on bone regeneration in a rat calvarial defect model, not only through the osteogenic potential of ASCs, but also through the release of cytokines by platelets in PRP, which, in turn, support ASCs.In this chapter, we introduce the bone regeneration using a combination of ASCs and PRP in a rat calvarial defect model.

Current status of bone regeneration using adipose-derived stem cells.

Many bone regeneration therapies have been developed for clinical use and have variable outcomes and serious limitations. The goal of bone regeneration is to repair a bone defect in a stable and durable manner. Cellular strategies play an important role in bone tissue engineering. Clinical factors important for successful bone regeneration are the recruitment of cells to the defect site and the production of a suitable extracellular matrix consistent with bone tissues. Adipose-derived stem cells (ASCs) can be obtained in large quantities with little donor site morbidity or patient discomfort. They are multipotent somatic stem cells and have a strong potential to differentiate and secrete growth factors. In this review, we discuss the osteogenic potential of ASCs with/without several types of scaffolds in vivo and their clinical application for bone regeneration.

A Low-Level Carbon Dioxide Laser Promotes Fibroblast Proliferation and Migration through Activation of Akt, ERK, and JNK.

BACKGROUND: Low-level laser therapy (LLLT) with various types of lasers promotes fibroblast proliferation and migration during the process of wound healing. Although LLLT with a carbon dioxide (CO2) laser was also reported to promote wound healing, the underlying mechanisms at the cellular level have not been previously described. Herein, we investigated the effect of LLLT with a CO2 laser on fibroblast proliferation and migration. MATERIALS AND METHODS: Cultured human dermal fibroblasts were prepared. MTS and cell migration assays were performed with fibroblasts after LLLT with a CO2 laser at various doses (0.1, 0.5, 1.0, 2.0, or 5.0 J/cm2) to observe the effects of LLLT with a CO2 laser on the proliferation and migration of fibroblasts. The non-irradiated group served as the control. Moreover, western blot analysis was performed using fibroblasts after LLLT with a CO2 laser to analyze changes in the activities of Akt, extracellular signal-regulated kinase (ERK), and Jun N-terminal kinase (JNK), which are signaling molecules associated with cell proliferation and migration. Finally, the MTS assay, a cell migration assay, and western blot analysis were performed using fibroblasts treated with inhibitors of Akt, ERK, or JNK before LLLT with a CO2 laser. RESULTS: In MTS and cell migration assays, fibroblast proliferation and migration were promoted after LLLT with a CO2 laser at 1.0 J/cm2. Western blot analysis revealed that Akt, ERK, and JNK activities were promoted in fibroblasts after LLLT with a CO2 laser at 1.0 J/cm2. Moreover, inhibition of Akt, ERK, or JNK significantly blocked fibroblast proliferation and migration. CONCLUSIONS: These findings suggested that LLLT with a CO2 laser would accelerate wound healing by promoting the proliferation and migration of fibroblasts. Activation of Akt, ERK, and JNK was essential for CO2 laser-induced proliferation and migration of fibroblasts.

Adipose-Derived Stem Cells Improve Collagenase-Induced Tendinopathy in a Rat Model.

BACKGROUND: Tendinopathy is a common and highly prevalent musculoskeletal disorder characterized by repetitive activity-related pain and focal tendon tenderness. Histopathologically, tendinopathic tissue mainly shows degenerative changes. Therefore, tendinopathy is not affected by anti-inflammatory therapies. A novel approach, including a stem cell-based therapy, may be beneficial for its treatment. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate the effects of adipose-derived stem cells (ASCs) on tendon healing in a rat tendinopathy model. The hypothesis was that ASC transplantation would improve degeneration in collagenase-induced tendinopathy. STUDY DESIGN: Controlled laboratory study. METHODS: Sixteen F344/NSlc rats underwent collagenase injection into the Achilles tendon to induce tendinopathy. At 1 week after collagenase injection, 8 rats received ASCs (ASC group) and 8 received phosphate-buffered saline alone (PBS group). Animals were sacrificed at 4 or 12 weeks after ASC administration, and the degree of degeneration in each tendon was histologically evaluated according to the Bonar scale. The microstructure of healing tendons was observed by scanning electron microscopy. Reverse-transcription polymerase chain reaction (RT-PCR) was performed to measure the ratio of type III collagen messenger RNA (mRNA) to type I collagen mRNA in tendons. RESULTS: The median Bonar scale score in the ASC and PBS groups was 2.5 and 5.33 at 4 weeks after treatment and 1.0 and 4.0 at 12 weeks after treatment, respectively. Histologically, the ASC group showed a significantly lower degree of tendon degeneration than the PBS group at both time points. In the RT-PCR analysis, the ratio of type III collagen to type I collagen was significantly lower in the ASC group than in the PBS group at 12 weeks after treatment. Moreover, this ratio decreased over time in the ASC group, whereas it increased over time in the PBS group. CONCLUSION: The study findings demonstrate that the application of ASCs results in significant improvement in the pathological findings associated with tendinopathy and the normalization of collagen ratios within the affected tendon. CLINICAL RELEVANCE: Subcutaneous adipose tissue can be harvested easily, and ASC administration might have the potential to rapidly treat tendinopathy.

Japan's challenges of translational regenerative medicine: Act on the safety of regenerative medicine.

The first issue of Nature Medicine published 20 years ago featured an article that reported Japan's critical situation regarding clinical trials, calling for major reform. Twenty years later, Japan has enacted three laws to promote the use of regenerative medicine as a national policy. The first law to be enacted was the Regenerative Medicine Promotion Act, which represents the country's determination to work toward the promotion of regenerative medicine. Subsequently, the Pharmaceuticals, Medical Devices, and Other Therapeutic Products Act (PMD Act) and the Act on the Safety of Regenerative Medicine (RM Act) came into effect. The PMD Act created a new category for regenerative medicine products, and established the process for obtaining approval for cell therapy and other regenerative therapies through the implementation of clinical trials. The RM Act specified the regulations that doctors, review committees, and cell culture/processing facilities must adhere to when providing regenerative medicine in medical care, not only in clinical research but also in private practice. Previously, researchers in regenerative medicine only had a set of guidelines to follow for conducting clinical research. Now, with the enactment of the RM Act, all areas for improvement that had been enumerated 20 years ago-such as the lack of appropriate review committees and governmental control-have been addressed by law, creating a system that gives the highest priority to patient safety. In this paper, we present the particularly noteworthy points of the RM Act, along with the actual current conditions of regenerative medicine in Japanese medical care.

Proapoptotic effect of control-released basic fibroblast growth factor on skin wound healing in a diabetic mouse model.

The ability of basic fibroblast growth factor (bFGF) to improve wound healing is attenuated by its short half-life in free form. This study aimed to enhance skin wound healing in a diabetes mouse model while concomitantly decreasing scar formation using control-released bFGF together with acidic gelatin hydrogel microspheres (AGHMs). Bilateral full-thickness wounds (10 mm in diameter) were made on the backs of db/db mice. Forty-five mice were divided into three groups, and the base of the wound under the panniculus carnosus and the wound periphery were injected with phosphate-buffered saline (300 µL) containing (1) control-released bFGF (50 µg), (2) control-released bFGF (20 µg), or (3) AGHMs alone. The size of the wound area was recorded on each postoperative day (POD). Mice were sacrificed on postoperative day 4, 7, 10, 14, and 28, and skin wound specimens were obtained to assess the endothelium/angiogenesis index via cluster of differentiation 31 immunohistochemistry, the proliferation index via Ki-67 immunohistochemistry, and the myofibroblast and fibroblast apoptosis indices by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling and alpha-smooth muscle actin or vimentin staining, respectively. Epithelialization rates and indices of proliferation and myofibroblast/fibroblast apoptosis were higher in the bFGF groups than in the AGHM group, mainly within 2 weeks of injury. No dose-effect relationship was found for control-released bFGF, although the actions of 50 µg bFGF seemed to last longer than those of 20 µg bFGF. Therefore, control-released bFGF may accelerate diabetic skin wound healing and induce myofibroblast/fibroblast apoptosis, thereby reducing scar formation.

Coadministration of adipose-derived stem cells and control-released basic fibroblast growth factor facilitates angiogenesis in a murine ischemic hind limb model.

OBJECTIVE: Adipose-derived stem cells (ASCs) have angiogenic potential owing to their differentiation into endothelial cells and their release of angiogenic growth factors to elicit paracrine effects. In addition, control-released basic fibroblast growth factor (bFGF) sustained with a gelatin hydrogel also supports effective angiogenesis. We sought to determine if coadministration of ASCs and control-released bFGF into murine ischemic limbs facilitates angiogenesis. METHODS: Levels of growth factors in the conditioned media of ASCs cultured with or without control-released bFGF were measured by enzyme-linked immunosorbent assays. A murine ischemic hind limb model was generated and intramuscularly injected with the following: gelatin hydrogel (group 1), a high number of ASCs (group 2), control-released bFGF (group 3), a small number of ASCs and control-released bFGF (group 4), and a high number of ASCs and control-released bFGF (group 5). Macroscopic and microscopic vascular changes were evaluated until day 7 by laser Doppler perfusion imaging and histologic analyses, respectively. RESULTS: Secretion of hepatocyte growth factor, vascular endothelial growth factor, and transforming growth factor-ß1 was enhanced by control-released bFGF. Vascular improvement was achieved in groups 4 and 5 according to laser Doppler perfusion imaging. Hematoxylin and eosin staining and CD31 immunohistochemical staining demonstrated an increase in the vascular density, vessel diameter, and thickness of vessel walls in groups 4 and 5. Cells positively stained for CD146, α-smooth muscle actin, and transforming growth factor-ß1 were observed around vessel walls in groups 4 and 5. CONCLUSIONS: These findings suggest that coadministration of ASCs and control-released bFGF facilitates angiogenesis in terms of vessel maturation in a murine ischemic hind limb model.

Adipose tissue-derived mesenchymal stem cells and platelet-rich plasma: stem cell transplantation methods that enhance stemness.

Because of their ease of isolation and relative abundance, adipose-derived mesenchymal stem cells (ASCs) are a particularly attractive autologous cell source for various therapeutic purposes. ASCs retain a high proliferation capacity in vitro and have the ability to undergo extensive differentiation into multiple cell lineages. Moreover, ASCs secrete a wide range of growth factors that can stimulate tissue regeneration. Therefore, the clinical use of ASCs is feasible. However, the potential of ASCs differs depending on the donor's medical condition, including diseases such as diabetes. Recent studies demonstrated that ASCs from diabetic donors exhibit reduced proliferative potential and a smaller proportion of stem cell marker-positive cells. Therefore, to ensure the success of regenerative medicine, tissue engineering methods must be improved by the incorporation of factors that increase the proliferation and differentiation of stem/progenitor cells when autologous cells are used. Platelet-rich plasma (PRP), which contains high levels of diverse growth factors that can stimulate stem cell proliferation and cell differentiation in the context of tissue regeneration, has recently been identified as a biological material that could be applied to tissue regeneration. Thus, co-transplantation of ASCs and PRP represents a promising novel approach for cell therapy in regenerative medicine. In this review, we describe the potential benefits of adding PRP to ASCs and preclinical and clinical studies of this approach in various medical fields. We also discuss the mechanisms of PRP action and future cell-based therapies using co-transplantation of ASCs and PRP.

New Japanese initiatives on stem cell therapies.

Two laws aiming to provide a new legal framework to promote regenerative medicine, while ensuring the efficacy and safety of the treatments, came into effect in Japan on November 25, 2014. The scope of these laws is briefly described here.