Down syndrome (DS) is caused by trisomy for human chromosome 21. Individuals with DS commonly exhibit mental retardation, which is associated with abnormal brain development. In the neocortex of the DS brain, the density of neurons is markedly reduced, whereas that of astrocytes is increased. Similar to abnormalities seen in DS brains, mouse models of DS show deficits in brain development, and neural progenitor cells that give rise to neurons and glia show dysregulation in their differentiation. These suggest that the dysregulation of progenitor fate choices contributes to alterations in the numbers of neurons and astrocytes in the DS brain. Nevertheless, the molecular basis underlying these defects remains largely unknown. We showed that the overexpression of two human chromosome 21 genes, DYRK1A and DSCR1, contributes to suppressed neuronal differentiation of progenitors in the Ts1Cje mouse model of DS. In addition, the effect of DYRK1A and DSCR1 overexpression on neuronal differentiation is mediated by excessive attenuation of the transcription factor NFATc. Additionally, we demonstrated that an increased dosage of DYRK1A contributes to elevated potential of Ts1Cje progenitors to differentiate into astrocytes and enhanced astrogliogenesis in the Ts1Cje neocortex. Further, we linked the increased dosage of DYRK1A to dysregulation of STAT, a transcription factor critical for astrogliogenesis. Together, our studies identify critical pathways responsible for the proper differentiation of neural progenitors into neurons and astrocytes, with direct implications for the anomalies in brain development observed in DS.
Down syndrome (DS) patients demonstrate the neuropathology of Alzheimer's disease (AD) characterized by the formation of senile plaques and neurofibrillary tangles by age 40-50 years. It has been considered for a number of years that 1.5-fold expression of the gene for the amyloid precursor protein (APP) located on chromosome 21 leading to overproduction of amyloid-β peptide (Aβ) results in the early onset of AD in adults with DS. However, the mean age of onset of familial AD with the Swedish mutation on APP which has high affinity for β-secretase associated with a dramatic increase in Aβ production is about 55 years. This paradox indicates that there is a poor correlation between average ages of AD onset and the theoretical amount of Aβ production and that there are factors exacerbating AD on chromosome 21. We therefore focused on dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A), since overexpressing transgenic mice show AD-like brain pathology. The overexpression of DYRK1A caused suppression of the activity of neprilysin (NEP), which is a major Aβ-degrading enzyme in the brain, and phosphorylation at the NEP cytoplasmic domain. NEP activity was markedly reduced in fibroblasts derived from DS patients compared with that in fibroblasts derived from healthy controls. This impaired activity of NEP was rescued by DYRK1A inhibition. These results show that DYRK1A overexpression causes suppression of NEP activity through its phosphorylation in DS patients. Our results suggest that DYRK1A inhibitors could be effective against AD not only in adults with DS but also in sporadic AD patients.
Down syndrome, caused by the triplication of human chromosome 21, is the most frequent genetic cause of mental retardation. Mice with a segmental trisomy for mouse chromosome 16, which is orthologous to human chromosome 21, exhibit abnormalities similar to those in individuals with Down syndrome and therefore offer the opportunity for a genotype-phenotype correlation. In the current review, I present several mouse lines with trisomic regions of various lengths and discuss their usefulness for elucidating the mechanisms underlying Down syndrome-associated developmental cognitive disabilities. In addition, our recent comprehensive study attempting to identify molecules with disturbed expression in the brain of a mouse model of Down syndrome in order to develop a pharmacologic therapy for Down syndrome is described.
A disintegrin and metalloproteinase with thrombospondin motif-1 (ADAMTS1) was initially cloned from a colon cachexia cell line. In the last 20 years, novel matrix metalloproteinase (MMP) genes were found, and in addition to their original members (MMPs and membrane-type MMPs), the current MMP family contains a disintegrin and metalloproteinases (ADAMs) and ADAMTS. ADAM and ADAMTS play essential roles in organogenesis as well as various diseases including osteoarthritis. ADAMTS has 19 members and can be divided into several groups according to their substrates. ADAMTS1, the first member of ADAMTS identified, is located on chromosome 21 very close to another ADAMTS member, ADAMTS5. Interestingly, ADAMTS1 is not highly expressed in normal tissues. One stimulation such as inflammation quickly induces ADAMTS1 expression. We found that hypoxia induced ADAMTS1 expression in endothelial cells, and serum ADAMTS1 levels were elevated in acute myocardial infarction patients. Once the artery was reperfused, the serum ADAMTS1 level quickly returned to the normal level. We also found that ADAMTS1 has specific roles in angiogenesis and lymphangiogenesis, and these functions were not related to its protease activity. It is also interesting that ADAMTS1 is likely to have a unique role in the tumor microenvironment. We also analyzed ADAMTS1-deficient mice and the results suggested that ADAMTS1 has diverse biological functions.
Monoclonal antibodies have been considered promising therapeutic entities due to their highly specific binding to antigens. For oncology in particular, the tumor specific binding of an antibody, without affecting normal tissue, is considered an ideal cancer therapy. Although the proposed mechanism of action of antibody therapeutics varies by targets and indications, antibody-dependent cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), ligand neutralization and inhibition of the signaling pathway are commonly used. Recent advances in genomic information, genetic engineering, and transgenic technology have greatly accelerated drug development processes. It is also possible to add new functions to antibody molecules through molecular engineering. For example, antibody-drug conjugates (ADC), which combine a monoclonal antibody and a small-molecule cytotoxic drug, have been successfully used for cancer treatment. It has been more than 20 years since the first therapeutic antibody was approved in Japan, and there are now more than 30 antibodies on the market, with many new molecules under development. Despite some drawbacks and challenges, antibody therapeutics hold great promise as we advance our knowledge and technologies in the coming years.
As an alternative to hybridoma technology, the antibody phage library system can also be used for antibody selection. This method enables the isolation of antigen-specific binders through an in vitro selection process known as biopanning. While it has several advantages, such as an avoidance of animal immunization, the phage cloning and screening steps of biopanning are time-consuming and problematic. Here, we introduce a novel biopanning method combined with high-throughput sequencing (HTS) using a next-generation sequencer (NGS) to save time and effort in antibody selection, and to increase the diversity of acquired antibody sequences. Biopannings against a target antigen were performed using a human single chain Fv (scFv) antibody phage library. VH genes in pooled phages at each round of biopanning were analyzed by HTS on a NGS. The obtained data were trimmed, merged, and translated into amino acid sequences. The frequencies (%) of the respective VH sequences at each biopanning step were calculated, and the amplification factor (change of frequency through biopanning) was obtained to estimate the potential for antigen binding. A phylogenetic tree was drawn using the top 50 VH sequences with high amplification factors. Representative VH sequences forming the cluster were then picked up and used to reconstruct scFv genes harboring these VHs. Their derived scFv-Fc fusion proteins showed clear antigen binding activity. These results indicate that a combination of biopanning and HTS enables the rapid and comprehensive identification of specific binders from antibody phage libraries.
Nearly fifty monoclonal antibodies have been approved to date, and the market for monoclonal antibodies is expected to continue to grow. Since global competition in the field of antibody therapeutics is intense, we need to establish novel antibody engineering technologies to provide true benefit for patients, with differentiated product values. Bispecific antibodies are among the next generation of antibody therapeutics that can bind to two different target antigens by the two arms of immunoglobulin G (IgG) molecule, and are thus believed to be applicable to various therapeutic needs. Until recently, large scale manufacturing of human IgG bispecific antibody was impossible. We have established a technology, named asymmetric re-engineering technology (ART)-Ig, to enable large scale manufacturing of bispecific antibodies. Three examples of next generation antibody therapeutics using ART-Ig technology are described. Recent updates on bispecific antibodies against factor IXa and factor X for the treatment of hemophilia A, bispecific antibodies against a tumor specific antigen and T cell surface marker CD3 for cancer immunotherapy, and bispecific antibodies against two different epitopes of soluble antigen with pH-dependent binding property for the elimination of soluble antigen from plasma are also described.
Fcγ receptors (FcγRs), which bind to the Fc regions of antibodies, play an important role in antibody effector functions. In humans, there are four types of activating FcγRs: FcγRI, FcγRIIa, FcγRIIIa, and FcγRIIIb. These are expressed on various effector cells such as natural killer (NK) cells, neutrophils and macrophages. FcγRIIIa expressed on NK cells is known to play a pivotal role in antibody-dependent cellular cytotoxicity (ADCC) by therapeutic monoclonal antibodies (mAbs). To assess the ADCC activity of mAbs, the killing of target cells is often measured using human peripheral mononuclear blood cells (hPBMCs) or isolated primary NK cells as effector cells. These assays can directly assess the cytotoxicity induced by mAbs, but require fresh blood from donors, and are insufficiently reproducible due to differences in effector cell activity among donors. We developed a cell-based assay using reporter cell lines expressing human FcγR and a nuclear factor of activated T cells (NFAT)-driven luciferase reporter gene (Jurkat/FcγR/NFAT-Luc), which can estimate the activation of various FcγRs by antigen-bound mAbs in vitro, with high reproducibility. The usefulness of this assay was confirmed by comparing mAbs activity with different abilities to activate FcγRs, including Fc-engineered anti-CD20 mAbs and anti-EGFR mAbs with different IgG subclasses. We also confirmed the application of this assay for the characterization of mAbs product-related substances. Our FcγR reporter assay is a promising new tool for the characterization of therapeutic mAbs in various stages of mAbs development.
In 2002, the Centre for the Advancement of Interprofessional Education (CAIPE) defined interprofessional education (IPE) as: Interprofessional Education occurs when two or more professions learn with, from, and about each other to improve collaboration and the quality of care. Since 2005, also in Japan, IPE has been introduced within educational institutions to train professionals in healthcare and welfare. Within pharmaceutical education, to acquire the “10 qualities required for pharmacists” indicated by revised model core curricula for pharmaceutical education in 2015, IPE is thought quite important. Meanwhile, highly advanced medical treatment is rapidly developing, and as a consequence home healthcare and long-term care must also be enlarged. As a countermeasure, an integrated community care system must be established, and pharmacists will be responsible for urgent tasks within the system. Four universities—Prefectural University, Saitama Medical University, Josai University, and the Nippon Institute of Technology—decided to implement a collaborative project with the philosophy of “realizing high-quality lifestyles for local residents”. This project was adopted by the Ministry of Education, Culture, Sports, Science and Technology as a Program for Promoting Inter-University Collaborative Education for fiscal year 2012. In this symposium, I report on the relationship between this initiative and pharmacy education, as well as discuss expectations of IPE for pharmacist education in the future.
At Showa University, which consists of the schools of medicine, dentistry, pharmacy, nursing and rehabilitation sciences, systematic interprofessional education was introduced with the cooperation of all 4 schools and through all undergraduate grades with the purpose of training medical staff who can contribute positively to the medical team. In the lower grades, students study the basics of medical team care based on a 4-school joint curriculum of experience learning (such as early exposure) and problem-based learning (PBL) tutorial inside and outside of the university. In the upper grades, students study the practice of medical team care by joint curriculum of participatory learning in the hospitals and community so as to acquire practical skills. Since 2014, we introduced systematic interprofessional education for home care and narrative-based medicine. Through these curriculums, I expect that the number of medical staff who actively promote patient-centered team medical care in a variety of medical fields, including hospitals and community, will continue to grow in the future.
Due to the rapid aging of the population, it has become important to ensure the provision of primary health care services. To respond to this challenge, it will be insufficient to offer services only at medical institutions; indeed, there are extremely high expectations for pharmacists because they work in close contact with the population at drugstores and pharmacies. Moreover, the Japanese government intends to promote family pharmacies (pharmacists) that not only prepare drugs but also give advice on health issues. In this context, pharmacists are expected to play new roles that surpass those in the existing framework, and this will require a new program to facilitate the acquisition of new abilities (skill mix). As an example, we would like to introduce an education program for pharmacists designed to develop clinical reasoning skills for patients' symptoms. To care properly for patients with symptoms and to decide whether to encourage self-medication or to recommend consultation with a doctor, pharmacists need to develop the ability to take a medical history in a systematic and reasonable way, and then to make an adequate assessment. Therefore on the basis of cooperation between doctors and pharmacists, we have developed an education program, as well as a medical interview support tool to assist pharmacists in obtaining necessary and comprehensive medical histories.
On January 1, 2015, the Interprofessional Education Research Center (IPERC) was opened at the Graduate School of Nursing at Chiba University, while being positioned as one of the Inohana Campus High Functionality Initiatives by the university. As the result of the establishment of an education research center in the nursing graduate school, various changes are coming into view. In particular, the active participation of young instructors of the medical, nursing, and pharmacology departments and university hospital in interprofessional education (IPE) efforts deserve special mention. In addition, IPE training with treatment participation, which had been a pending matter for many years, is being implemented on a trial basis in the university hospital ICU and pediatric departments starting this year. During this training, treatment plan proposals will be conducted in cooperation with university hospital specialists. IPE is also having a great influence on the formation of curriculums in each department. A factor behind this is the awareness of issues by young instructors such as whether practical training fully utilizes the team building, conference management, and joint learning ability being nurtured at IPE. IPE is unable to perform fundamental education without influencing professional education, and professional education also cannot help but change into “training of specialists with the ability to make contributions considered necessary as a specialist under any circumstances”, The degree to which instructors in these three departments can together support curbing of resistance to this change and promoting transformation of values is considered key.
Activities related to interprofessional education (IPE) vary between countries according to local and national health needs and systems. The International Pharmaceutical Federation (FIP) Education Initiative endeavors to provide a global vision in IPE by the sharing of experiences and gathering of evidence collaboratively to facilitate country-level initiatives. The purpose of this paper is to contribute to the further development of IPE activities in pharmacy in Japan through sharing global perspectives and activities related to IPE. FIP Education Initiative published the Interprofessional Education in a Pharmacy Context: Global Report in September 2015, which marked a milestone in the growing recognition of IPE in pharmacy globally. The paper shared global and regional perspectives and experiences in IPE in pharmacy, both from the report and FIP activities. This paper can be seen as a snapshot of IPE-related international activities, which enables gaps and challenges in implementing IPE activities in Japan to be identified. This paper provides an opportunity to explore global trends and initiatives regarding IPE, and to consider how to form and implement IPE specifically based on Japanese health needs and systems.
In 2009, the Japan Anti-Doping Agency (JADA) established the “Sports Pharmacist Accreditation Program” to prevent doping in sports. Since then, anti-doping activities in Japan have been attracting attention. In this study, we investigated research about the current status of doping from 2007 to 2014 in Japan to make anti-doping activities more concrete, and we also discussed future anti-doping activities by pharmacists. In Japan, bodybuilding was the sporting event with the highest number and rate of doping from 2007 to 2014. Many of the positive doping cases were detected for class S1 (anabolic agents), S5 (diuretics and masking agents), and S6 (stimulants). Within class S1, supplements were the main cause of positive doping. Within class S5, medicines prescribed by medical doctors were the main cause of positive doping. Within class S6, non-prescription medicines (e.g., OTC) were the main cause of positive doping. When we looked at the global statistics on doping, many of the positive doping cases were detected for class S1. On comparing the Japanese statistics with the global statistics, the rate of positive doping caused by class S1 was significantly lower, but that caused by classes S5 and S6 was significantly higher in Japan than in the world. In conclusion, pharmacists in Japan should pay attention to class S1, S5, and S6 prohibited substances and to the sport events of bodybuilding. Based on this study, sports pharmacists as well as common pharmacists should suggest new anti-doping activities to prevent doping in the future.
Kidney disease (KD) is a serious risk factor for cardiovascular event, and it is important to protect the heart and kidneys during treatment of the high blood pressure to prevent cardiovascular event. Japanese guideline (JSH2014) suggests using combination therapy to reduce the risk of comorbidities rather than high-dose monotherapy for the patients with cardiovascular disease and KD. Therefore, the present study assessed antihypertensive prescription patterns in Japanese patients with ischemic heart disease related diseases (IHDRD) and KD, and evaluated whether the prescription patterns match with the guideline-suggested therapies by analyzing the national insurance claims database (NDB). We extracted antihypertensive prescription patterns among Japanese IHDRD patients from the data of October 2011 of NDB, and examined the effect of KD on the prescription patterns. The number of prescribed antihypertensive was associated with KD among patients regardless of IHDRD. Patients with IHDRD and KD were more frequently prescribed combination therapy (calcium channel blockers/angiotensin II receptor blockers) than the calcium channel blocker monotherapy, based on the JSH2014. On the other hand, we did not observe the standard use of diuretics for patients with heart failure, which is suggested by the JSH2014. These findings suggested that patients with IHDRD and KD were frequently prescribed combination therapy to achieve its cardioprotective and renoprotective effects, according to the JSH2014, but the prescription profile to the patients with heart failure didn't match that of guideline-suggested therapies. This study provided a clinically important information and demonstrated the utility of NDB for compliance assessment for therapeutics guideline.
A high dietary intake of phosphorus is considered to be a significant health threat for hemodialysis (HD) patients. Prescription medications, which might be a major source of phosphorus, is largely unrecognized in Japan. However, the amount of phosphorus indicated on the package label, is not quantified. In this study, the phosphorus content of 22 of the most widely prescribed medications that are used in conjunction with HD therapy were examined and differences between branded and generic prescription medications were compared. All samples were selected from medications that are typically prescribed for HD patients. The samples were ground prior to analysis. Phosphorus was measured using the Wako L-Type Phosphate method. All instruments used in the study were calibrated according to the manufacturers' specifications. Amlodipine (15 mg/tablet) and paroxetine (30.0 mg/tablet) were found to contain higher contents of phosphorus than the medications tested. Differences in phosphorus content between branded and generic drugs was also determined. The phosphorus content of all generic paroxetine preparations was significantly lower than the values for identical branded medications. On the other hand, the phosphorus content of several generic amlodipine preparations were significantly different from those of similar, branded preparations. Specific information regarding the phosphorus content of prescribed medications used by HD patient needs to be made available to the dialysis community.
Warfarin (WF) shows a number of interactions with other drugs, which alter its anticoagulant effects. The albumin binding interaction is one such pharmacokinetic mechanism of drug interaction with WF, which induces a rise in the free WF concentration and thus increases the risk of WF toxicity. Teicoplanin (TEIC) is an anti-methicillin-resistant Staphylococcus aureus drug, which also binds strongly to albumin in the plasma. Therefore, co-administration of TEIC may displace WF from the albumin binding site, and possibly result in a toxicity. The present study was performed to investigate the drug-drug interaction between WF and TEIC in comparison with controls treated with vancomycin (VCM), which has the same spectrum of activity as TEIC but a lower albumin binding ratio.The records of 49 patients treated with WF and TEIC or VCM at Fukuoka University Hospital between 2010 and 2015 were retrospectively reviewed. These 49 patients consisted of 18 treated with TEIC in combination with WF, while 31 received VCM in combination with WF. Prothrombin time-international normalized ratio (PT-INR) showed a significant increase of 80.9 (52.0-155.3) % after co-administration of TEIC with WF. In contrast, the rate of PT-INR elevation associated with VCM plus WF was 30.6 (4.5-44.1) %. These observations suggested that TEIC can cause a rise in free WF concentration by albumin binding interaction. Therefore, careful monitoring of PT-INR elevation is necessary in patients receiving WF plus TEIC.
Bacteremia is one of the most serious infectious illness resulting from nosocomial infection. Therefore, appropriate antimicrobial chemotherapy should be provided as soon as possible to patients exhibiting symptoms of infectious disease and having positive blood culture results. Antimicrobial stewardship (AS) guidelines were recently released by the Infectious Diseases Society of America. The guidelines recommend “proactive intervention and feedback” as one of the core strategies for implementing optimal antimicrobial drug use to improve patient outcomes in clinical settings. We began using the AS program for optimizing antimicrobial chemotherapy in patients with positive blood culture results. The results of blood cultures and antimicrobial prescriptions for the corresponding patients were daily reviewed by a pharmacist and a physician, members of the infection control team (ICT). If the antimicrobial agents selected were inappropriate, ICT made a recommendation to the attending physicians who prescribed the antibiotics. To evaluate the outcomes of this program, we conducted a single-center, retrospective investigation for near a hundred of patients who underwent intervention by infection-control physician and pharmacist. Resolution of bacteremia (determined by blood culture results) was 96.3% in the group that accepted intervention, whereas only 16.7% of the cases resolved in the group that did not accept intervention. These results strongly suggest the importance of the infection disease-specialist team intervention. This program could become an important method for improving clinical outcomes in patients with bacteremia.