When an organism is exposed to a viral infection, a variety of pathologies develop over a long period and across multiple organs. This involves factors on the viral side, those on the host side, and social factors. Viral factors are defined by viral genome information, including viral genome mutations. Factors on the host side include epigenomic modifications acquired through aging and environmental factors, in addition to human whole-genome information. Social factors include lifestyle changes, such as exercise, diet, and conversation, due to epidemics of viral infections. In the chronic phase, more than 200 sequelae　(e.g., Long COVID) occur, including neurological symptoms (depression, cognitive impairment, and sleep disturbances). By integration of the basic, clinical, and systems biological analyses, we have shown the operating principles of host life systems in response to viral infection with coronaviruses (SARS-CoV and SARS-CoV2) and influenza viruses. In the present time, I would like to talk about the pathogenesis of severe viral infections and sequelae, and the possibility of drug discovery, focusing on our findings.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for COVID-19, continues to spread around the world and has caused millions of deaths to date. In an effort to develop therapeutics and preventive measures, we are performing numerous research projects with this virus and its variants. In this presentation, I will discuss our findings regarding animal models and their value as tools for evaluating countermeasures against SARS-CoV-2.

As a leading company in the infectious disease field, SHIONOGI has been pursuing the discovery and development of new drugs for diseases such as HIV, influenza, AMR, and COVID-19.

In my presentation, I’m going to share our activities in the infectious disease area, as well as what we have learned from the COVID-19 pandemic about preparedness and the ideal partnership between the public and private sectors required to protect society from arising dangers.

First, I would like to talk about SHIONOGI’s R&D activities and contributions to healthcare in the infectious disease field, an area that many pharmaceutical companies have withdrawn from. In addition, by sharing the difficulties we faced in the development of a COVID-19 drug, I would like to discuss the importance of preparedness for pandemic threats even during normal times, including steps that have been taken in this direction in Japan, such as the establishment of SCARDA and the creation of an emergency approval system.

From here forward, it is expected that Japanese industry, government, and academia will work more closely together to respond to emergencies, with their efforts facilitated by new systems that have been and will be created. In order to meet this expectation, it is required that all sectors share a common perspective regarding the need to improve such capabilities and thereby to prepare effectively. I hope that my presentation can be of some help in achieving the necessary alignment.

At Takeda, the patients we serve — and achieving outcomes for them and their health — have been at the heart of everything we do for more than 240 years. We believe our values, making decisions based on Patient – Trust – Reputation – Business, in that order, sets us apart.

Takeda has transformed into a global, science-driven, digital biopharmaceutical company and has accelerated our competitiveness in past several years. Our global footprint, robust financial position, balanced portfolio, and diverse talent gives us the scale needed to bring innovative medicines to patients across the world. Through our R&D transformation, we clarified our focus on well-defined therapeutic areas, diversified our modalities beyond small molecules, and enhanced internal research capabilities and external collaborations which enabled us to make a more meaningful impact on patients and society.

Today, with health care systems increasingly under strain as life expectancies rise, populations age and innovative treatment options expand, our patient-centered and outcomes-focused approach is more relevant than ever. We believe that health care systems need to urgently move toward value-based health care, one that rewards outcome and care quality – the true purpose of any healthcare system. That is why our strategy is centered on the discovery and development of innovative and life-transforming medicines that have the potential to be best-in-class or first-in-class. At the same time, we are building resilience against external risks and making bold investments in data, technology, and AI to upskill our people and drive value creation.

Our culture encourages and appreciates our differences, and we believe the company continues to thrive because of them. We embrace our differences, and these diverse perspectives reflect the perspectives of the patients who rely on the treatments we develop. We ensure that employees, regardless of gender, age, nationality can advance their careers and fully demonstrate their capabilities. At Takeda, we are committed to create an exceptional experience for our people.

With particular relevance to the COVID-19 pandemic, Josef Penninger will presenthow work on ACE2 and its role in lung failure, from the discovery in fly heartdevelopment to the first mutant mice and a fundamental understanding of SARSCoronavirus. This data provided the first molecular underpinning why the firstSARS-CoV and now SARS-CoV2 causing COVID-19 became "dangerous viruses". ACE2 isthe critical receptor for SARS-Cov-2 and has taken center stage in globalresearch and drug and vaccine development. This work has also been translatedinto ACE2-based drugs as rational and universal prevention and treatmentstrategies for COVID-19.

In this talk, I introduce mathematical studies for foundation of preventive and preemptive medicine linking Life and Science on the basis of our Moonshot Goal 2 project on Comprehensive Mathematical Understanding of the Complex Control System between Organs and Challenge for Ultra-Early Precision Medicine, supported by the Cabinet Office,Government of Japan and JST. In particular, I explain details of mathematical sensitive detection of signs for deviation from healthy states, the DNB(Dynamical Network Biomarker) theory to detect fluctuations peculiar to pre-disease states before onset of diseases, and treatment of pre-disease states by control theory.

Antibody as a drug modality contributes to the first runner of biomedicine. Recently, research and development of next generation antibody drugs has remarkable progresses on therapy, e.g. antibody drug conjugate (ADC), bispecific antibody (bsAb), and single domain antibody (VHH, also called nanobody), which has widen the application areas of antibody drugs. These include combination of elemental technologies, and incorporation of information sciences into the drug development. Here I would discuss next generation drug modality, especially focusing on innovation-driven antibody engineering.

In this presentation, I would like to discuss the advent of the new era in genome-related technologies. In fact, a remarkable progress was made in this field in recent years, which may make a substantial effect on the future direction of genome research in Japan. First, I would like to look back at the rapid spread of single-cell analysis. The maturity of the preceding single-cell is further traced back to the dramatic expansion and spread of the sequencing capabilities of next-generation sequencers. Without the ability to analyze the whole human genome on a scale of tens of thousands to hundreds of thousands of people, it would have been impossible to perform genetic analysis on tens of thousands to hundreds of thousands of cells. However, as the single-cell technologies transforms into the gene expression analysis which preserves spatial position information, it is undergoing a major transformation into measurement which does not depend on sequences. The data produced here is mainly image data rather than the sequence data. Inevitably, there will be a major turning point in the way we have used data and databases. As a turning points in the next-generation sequencing era, which has swept the fields of medicine and biology for 10 years, I would like to share with the participants the enthusiasm of the current new era of genomic science. I hope this symposium should provide an opportunity to exchange opinions, rather than just providing information from my perspectives.

The nucleus is surrounded by nuclear envelope, a double membrane and about two or three thousand of nuclear pores per one nucleus exist in the nuclear envelope. The nuclear pore complex is a huge structure and consists of about 30 different proteins. A short fiber-like structure extends into the cytoplasm, while a basket-like structure extends into the nucleoplasm. A variety of molecules, such as proteins and RNAs, are transported through the nuclear pores in both directions. The nuclear localization signal (NLS)-containing protein is recognized by importin a in the cytoplasm. Importin b binds to importin a to form a heterotrimeric complex. The trimeric complex translocates through the nuclear pore complex. After translocation of the complex through the nuclear pores, nuclear small GTPase Ran-GTP binds to importin b to trigger the dissociation of the complex. The NLS-substrates become free in the nucleoplasm. Then, importin a and importin b form distinct export complexes in the nucleus together with RanGTP and are recycled back to the cytoplasm by separate pathways. Then importin a and importin b are re-used for next rounds of transport. It has been recently elucidated that the nucleocytoplasmic transport machineries are involved in a variety of cell functions.

A fundamental question in understanding tissue development is how resident stem cells or multipotent progenitors give rise to the various cell types in appropriate numbers and at the right locations to achieve tissue organization. Neural stem/progenitor cells (NPCs) in the mammalian neocortex initially divide symmetrically to increase their pool size (expansion phase). They then start to divide asymmetrically and give rise to neuronal and glial cell types in a region- and developmental stage–dependent manner. In this talk, I will present data regarding the mechanisms underlying the transition from the expansion phase to the neurogenic phase and discuss their potential role in psychiatric diseases such as autism spectrum disorder.

I would also like to present our results regarding signaling pathways involved in innate immunity that regulate cell fate after viral infection.

With advances in DNA sequencing and various ‘omics’ technologies, it has becomepossible to capture changes in immune cells through the analysis of biologicallyactive substances such as cytokines and chemokines, as well as T- and B- cellreceptor sequence analysis in various pathological conditions and drugresponses. Furthermore, technological advances in the single cell level havemade it possible to understand the dynamic changes in immune cells in detail. Inaddition, it has been suggested that the immune responses activated through drugand HLA interaction play key roles in drug-induced skin hypersensitivity andhepatotoxicity. HLA class I molecules are associated with drug eruptions such asStevens-Johnson syndrome, and class II molecules with hepatotoxicity. In cancertreatment, it is becoming clear that the immune environment within cancertissues and throughout the body is important not only for cancer immunotherapybut also for the responsiveness of other anticancer drugs and radiation therapy.Changes in immune responses during the onset, remission, and progressionprocesses of various diseases have not been completely analyzed until now, butdevelopment of immunopharmacogenomics will certainly help to elucidate thesechanges.

“LEQEMBI”, the world's first disease-modifying therapy for Alzheimer's disease(AD), was approved in Japan in September of this year, following the UnitedStates, ushering in a new era in dementia treatment. Eisai Co., Ltd. has beenengaged in research and development in the field of dementia for more than 40years, continuing to overcome failures and diversify R&D risks. Although wesucceeded in developing the world's first AD drug "ARICEPT" in 1997, wecontinued to strive for next-generation drug discovery. We have developed avariety of new drug candidates based on the amyloid-β (Aβ) cascade hypothesis,which is the root cause of AD, but candidates have dropped out one afteranother. Among them, the anti-Aβ protofibril antibody “LEQEMBI” was developedthrough careful clinical research, utilizing the results of familial AD researchconducted in collaboration with academia. There is no success in drug discoverywithout failure, and by enduring failure, experience and knowledge areaccumulated. This experiential knowledge is the key to success in drug discoveryand is the “nautical chart” that guides the ship of new drug development on theright course. The presence of a captain who writes the charts and navigates thesea is also essential. I would like to take this opportunity to touch on “thespirit of drug discovery” that exists based on empathy with AD patients.

Schizophrenia is a serious mental disorder that develops from the late teens to the 30s. It is characterized by positive symptoms such as hallucinations and delusions, negative symptoms such as emotional flattening, and cognitive impairment. The etiology remains unknown, but both genetic and environmental factors are involved. Current antipsychotic drugs approved as therapeutic agents for schizophrenia improve positive symptoms, but have little effect on negative symptoms and cognitive impairment, and some individuals are treatment resistant. Serious side effects such as extrapyramidal symptoms are also a problem. Therefore, there is an urgent need to elucidate the disease mechanism and to develop novel therapeutic targets accordingly. We are addressing this issue by promoting translational research based on genome analysis in schizophrenia. Specifically, low-molecular-weight G-protein signaling has been suggested as a relevant pathological pathway. We have identified ARHGAP10 gene variants that are strongly associated with the disease, and have generated Arhgap10 gene-modified mice. In this lecture, I will introduce the antipsychotic-like effects of Rho-kinase inhibitors, along with current findings related to the pathological analysis of Arhgap10 gene-modified mice.

Epigenetics refers to a gene regulatory mechanism that integrates and coordinates genetic programs and environmental cues. It plays a critical role in various biological phenomena, such as cell fate decision, embryonic development, and cellular homeostasis. At the molecular level, epigenetic regulation is achieved by conformational changes in chromatin, depending on chemical modifications of DNA and histone proteins. Random X-chromosome inactivation in mammalian females is a typical epigenetic phenomenon, which for example gives diversity in coat color pattern of calico cats and tortoiseshell cats, but some environmental stresses, especially those imposed on fetuses and young can result in long-lasting epigenetic mis-regulation of genes and adult diseases. Thus, epigenetics can be viewed as an interface between genetics and environment. Normally, epigenetic modifications are reset when genetic information is transmitted to the next generation: however, some epigenetic changes, especially those induced by environmental stresses, can be heritable through the germline. In this talk, I will summarize the basics of epigenetic gene regulation and discuss some recent progress in epigenetics research.

Targeted goal of our project is to realize precision medicine of genetic diseases caused by aberrant splicing, induced by deep-intronic VUS. In eukaryotic gene expression system, a precursor mRNA transcribed from genome consists of exonic sequences and intervening intronic sequences, and exonic sequences are connected by RNA splicing reaction, resulting in production of protein-coding sequences. Splicing regulation is regulated by multiple factors, such as chromosomal structure, RNA cis-elements, and trans-acting splicing factors, and due to its complexity, precise prediction of alternative splicing profiles still remains to be achieved today. Recent accumulation of whole genome sequence data facilitated access to deep-intronic sequences, which provides essential information to understand splicing codes. Compared to conventional exome sequencing data, covering approximately 1% of genomic information, whole genome sequencing revealed presence of numerous VUS within the deep-intronic region, which are not accessed by exome studies. Our preliminary observations indicate there are many deep-intronic VUS that affect splicing code to create pseudoexonization of a given intronic region, resulting in pathogenesis by causing frameshifting or insertion, as we recently characterized for NEMO deficiency syndrome (J. Clin. Invest. 2019) and cystic fibrosis (Cell Chem. Biol. 2020).　To achieve our goal, we are challenging elucidation of splicing code using artificial intelligence (AI)-driven novel strategy. We will conduct a genome-wide functional annotation for deep-intronic VUS, for more than 10,000 whole genome sequence data available from Tohoku Medical Megabank (ToMMo), The 1,000 Genome Project, and Genome Asia 100k Project. We constructed an original AI and conduct a clinical trial to realize precision medicine of genetic diseases.

To better understand how drugs exert their effects in our human body, we should recognize that only a fraction of the mechanisms has been identified and described in the literature. In fact, affinities for all receptors, enzymes, and channels have not been measured during the development phase, and the safety in humans has been investigated in a limited number of cases within a short time frame. Accordingly, unexpected adverse events have been reported during post-marketing surveillance. Therefore, there will be numerous unknown effects of drugs buried in clinical data, which may contain not only adverse event mechanisms but also unexpected benefits. Then, how can we find out them? In this talk, I will introduce some of our achievements in finding unexpected beneficial effects of drugs from clinical real-world data (RWD).

(1) By statistical analysis of multiple RWD, we found that the anti-arrhythmic drug amiodarone caused interstitial lung injury with chronic inflammation of lung tissue leading to fibrosis, and that the concomitant use of the anti-thrombin drug dabigatran suppressed the incidence of such adverse events. Pharmacological studies revealed that this effect is due to the inhibition of PAR1-PDGFRα-MMP12 pathway by dabigatran.

(2) RWD showed that the anti-diabetic DPP4 inhibitors increased the risk of an autoimmune disease, bullous pemphigoid (BP), and that concomitant use of lisinopril, an antihypertensive drug widely used in the US, reduced the risk. Pharmacological studies revealed that lisinopril suppresses the development of BP by inhibiting cutaneous MMP9 expression through suppression of the ACE2-MasR pathway, rather than by acting on immune cell functions.

(3) Short-term administration of the antimicrobial fluoroquinolones increased the risk of tendinopathy after the use. Conventional treatment guidelines suggest that concomitant corticosteroid therapy increases the risk of tendinopathy. However, RWD analysis found a preventive effect of dexamethasone. Interestingly, dexamethasone also decreased the spontaneous incidence of tendinopathy in a aged cohort. From pharmacological studies, we found that fluoroquinolones impair tendon cells by DNA damage with generation of reactive oxygen species, whereas dexamethasone has a beneficial effect on tendon tissue function via increased expression of GPX3, a glutathione peroxidase that contributes as a radical scavenger.

Transporters are membrane proteins responsible for the distribution of substanceswithin the body, acting as interfaces between various compartments, thusdetermining the concentration ratios of substances between these compartments.Consequently, by pharmacologically modulating the function of thesetransporters, we can shift abnormal compound distributions seen in pathologicalstates, restoring homeostasis and thereby promoting recovery from diseases. Forinstance, the SGLT2 (SLC5A2) inhibitors, which suppress the reabsorption ofglucose in the renal tubules, is an exemplary drug that skews glucosedistribution towards the urine, enhancing glucose excretion and rectifyinghyperglycemia, establishing its role in diabetes treatment. From anotherperspective, transporters responsible for nutrient uptake, especially thoseupregulating in pathogenic cells like cancer cells, become potential drugtargets. The amino acid transporter LAT1 (SLC7A5), which is highly expressedwith specificity in cancer cells, presents itself as a potential diagnostic andtherapeutic target. In this lecture, introducing our research on drugdevelopment targeting LAT1 as an example, I would like to discuss theinteractions between transporters and compounds as well as the significance oftransporters as drug targets.

What are modern approaches to improve and augment brain function? In this talk, I will discuss what can be achieved by connecting the brain and artificial intelligence, explaining the research results and background of the ERATO Ikegaya Brain-AI Hybrid Project.

We will explain the outline of the medical DX project promoted by the Japanese government and the technologies involved, and explore issues and solutions in Japan, with reference to secondary use cases such as medical information sharing and analysis in other countries.

Neurodevelopmental disorders (NDDs) are a complex group of disorders resulting from disturbances of the nervous system that occur early in neurodevelopmental stages and present with complex interrelated symptoms. The number of people affected by NDDs in developed countries continues to increase, yet no curative medicine has yet been developed. To overcome the situation, it is important to establish a model of the disease using rodents, and a variety of models are needed to match the complex symptoms. Genetic analysis has so far identified many responsible/risk genes for NDDs, while environmental factors such as maternal drug exposure, maternal immune activation, and paternal aging are also known to induce NDDs. It is also important to develop analytical systems tailored to the symptoms. In this talk, I would like to introduce these pathological models analyzed in our laboratory and mention a new analysis system that utilizes artificial intelligence and machine learning with big data. Through this talk, I hope to discuss the latest research trends and methodologies for elucidating the etiopathogenesis of NDDs, to better understand the mechanisms, and to contribute to the development of promising therapeutic strategies in future.

The field of human biology faces three major technological challenges. Firstly, the causation problem is difficult to address in humans compared to model animals. Secondly, the complexity problem arises due to the lack of a comprehensive cell atlas for the human body, despite its cellular composition. Lastly, the heterogeneity problem arises from significant variations in both genetic and environmental factors among individuals. To tackle these challenges, we have developed innovative approaches. These include 1) mammalian next-generation genetics, such as Triple CRISPR for knockout (KO) mice and ES mice for knock-in (KI) mice, which enables causation studies without traditional breeding methods; 2) whole-body/brain cell profiling techniques, such as CUBIC, to unravel the complexity of cellular composition; and 3) accurate and user-friendly technologies for measuring sleep and awake states, exemplified by ACCEL, to facilitate the monitoring of fundamental brain states in real-world settings and thus address heterogeneity in human.

By integrating these three technologies, we have made significant progress in addressing two major scientific challenges in sleep research: 1) understanding sleep regulation (sleep mechanisms) and 2) determining the role of sleep (sleep functions). With regard to sleep mechanisms, we have recently proposed the phosphorylation hypothesis of sleep, which emphasizes the role of the sleep-promoting kinase CaMKIIα/CaMKIIβ (Tatsuki et al., 2016; Tone et al., 2022; Ode et al., 2020) and the involvement of calcium signaling pathways (Tatsuki et al., 2016). According to this novel perspective, the dynamics of calcium, representing neural activity during wakefulness, can be integrated and converted into the auto-phosphorylation status of CaMKIIα/CaMKIIβ, which induces and sustains sleep (Tone et al., 2022). Concerning sleep functions, we conducted computational studies to examine synaptic efficacy dynamics during sleep and wakefulness. Our findings led to the formulation of the Wake-Inhibition-Sleep-Enhancement (WISE) hypothesis, suggesting that wakefulness inhibits synaptic efficacy, while sleep enhances it.

During this talk, we will also present our discoveries regarding the identification of muscarinic acetylcholine receptors (Chrm1 and Chrm3) as essential genes of REM sleep. Furthermore, we will discuss new insights into psychiatric disorders, neurodevelopmental disorders, and neurodegenerative disorders derived from the phosphorylation hypothesis of sleep.

Biological membranes such as plasma membrane are formed by a phospholipid bilayer. Phospholipids have two fatty acyl chains attached to them, and these fatty acyl chains vary from saturated fatty acids to highly unsaturated fatty acids. The hydrophobic environment formed by these fatty acyl chains not only functions as a barrier between the inside and outside of the membrane, but also interacts with hydrophobic regions of membrane-bound proteins, which may affect the localization, stability, and function of membrane-bound proteins. For example, lipid rafts composed of sphingomyelin and cholesterol in the plasma membrane accumulate certain membrane proteins such as GPI-anchored proteins. We have found that dipalmitoylphosphatidylcholine (DPPC), whose phase transition temperature (42°C) is higher than body temperature, varies greatly in content from cell to cell, and that the function of a certain membrane receptor is greatly modified by the amount of DPPC. On the other hand, for example, phospholipids with highly unsaturated fatty acyl chains are abundant in the retina and play an important role in retinal function. We have generated a cell culture system deficient in highly unsaturated fatty acids and suggested the existence of a membrane-bound protein population requiring phospholipids with highly unsaturated fatty acid chains. As a result of advances in lipidome analysis and the elucidation of many lipid-metabolizing enzymes, we have reached a point where biomembrane fatty acid chains can be artificially regulated. Under these circumstances, it has become possible to comprehensively analyze the role of biomembrane fatty acid chains with respect to membrane-bound proteins.

In pharmacology textbooks, explanations are provided about the physiological activities of primarily five prostaglandins and thromboxane that are mainly produced through the activity of cyclooxygenase from the unsaturated fatty acid arachidonic acid, as well as the pharmacological actions of SAIDs and NSAIDs that inhibit their metabolism. With the advancement of omics technologies, it has become evident that not only these major lipid metabolites but also many other lipid metabolites dependent on various substrates and enzymes are produced and metabolized within the body. When comprehensively evaluating lipids produced and excreted in tissues and body fluids of diseased tissues or fluids, specific lipid production profiles reflecting each pathology are observed. These technologies can be applied as biomarkers and can also be used in the exploration of novel bioactive lipids. In our laboratory, we have utilized comprehensive concentration measurement techniques for bioactive lipids (lipidomics) to evaluate lipid profiles in tissues and body fluids of patients and animal models with allergic diseases such as food allergies, atopic dermatitis, and allergic rhinitis. Additionally, we have conducted explorations of the bioactivity of lipid metabolites produced therein. As a result, we have made discoveries related to biomarkers for food allergies and atopic dermatitis excreted in urine, as well as multiple lipids that exacerbate allergic inflammation. In this presentation, we would like to report these research findings.

Recently, oxidized phospholipids have been reported to be involved in various diseases. For example, lipid peroxides are involved in the induction of a new cell death form, "ferroptosis," and epoxidized ω3 fatty acids, an oxidized metabolite, are engaged in worsening allergies. Thus, although the importance of oxidized phospholipids is widely recognized in the induction of inflammation and cell death, the number of oxidized phospholipids available or detectable is limited. This lower number would be due to the lack of appropriate detection techniques.

Here, we have developed a fluorescent probe to detect "lipid-derived radicals," key molecules during the chain reaction of lipid peroxidation. Furthermore, since this probe can covalently bind to lipid-derived radicals, we have constructed an LC/FL/HRMS/MS system and have successfully analyzed the structures of 132 lipid-derived radical species. 　

Next, a non-targeted analysis of phosphatidylcholine-derived oxidized lipids (oxPCs) was performed using a high-resolution mass spectrometer, and a library of 465 oxPCs was constructed. Furthermore, we detected 70 kinds of oxPCs in mice with acetaminophen-induced acute liver failure, and mass imaging of oxidized lipids was successfully performed.

Furthermore, a novel screening system for oxidized lipid inhibition was developed. Notably, selecting compound had its inhibitory effect against retinal damages and bilateral common carotid artery occlusion model animals.

In this symposium, I would like to introduce our recent research and development status, including the detection and structural analysis of oxidized phospholipids and their application using animal models.

GTP-binding proteins (G proteins) are key intracellular signal mediators in response to extracellular physicochemical stimuli. The C-terminus of G proteins is a hypervariable region whose living structure is difficult to unravel, and we found that cysteine in this region has high redox activity and is involved in stress response and adaptation in the heart. We also revealed that the cysteine has a multiple sulfur atom-linked (supersulfide) residue (Cys -S_(n)SH, n≥1), which negatively regulates the functional activity of G proteins. Not only protein-bound supersulfides, but also intracellular inorganic supersulfides are highly nucleophilic and react positively with electrophilic lipid peroxides, which may act as an anti-oxidant and anti-cytotoxic agent. Furthermore, desupersulfidation of the mitochondria fission-accelerating G protein, dynamin-related protein 1, has been shown to promote the accumulation of lipid droplets in the liver due to high fat loading. In this symposium, we will also address the potential of sulfur-based lipid-redox interactions as a new therapeutic target.

In order to eliminate the bottleneck of non-clinical studies in infectious disease vaccine development research in Japan and to realize the 100-day mission, this study will bring together researchers in infectious disease vaccine research at Japan's top research institutions, the Institute of Medical Science of the University of Tokyo, the National Institute of Infectious Diseases, and the National Institute of Biomedical Innovation and Nutrition, to conduct GLP studies in small animals to primates, and to develop a new vaccine for infectious diseases. The three research institutes will collaborate with CROs capable of conducting GLP studies on small animals to primates, and under appropriate BSL management, will establish a research system that enables exploratory research and efficacy verification experiments for regulatory approval applications on novel coronaviruses, influenza viruses, and other unknown infectious pathogens, and will also develop a research system that will enable the development of young researchers. Promote seamless and borderless team building, including the development of young researchers.

Lab HP; https://vaccine-science.ims.u-tokyo.ac.jp/en/message/

U Tokyo Crowdfunding；https://utf.u-tokyo.ac.jp/project/pjt142

COVID-19 pandemic underscored the critical need for swift deployment of essential medical countermeasures, with vaccines playing a pivotal role. The successful development of vaccines hinges on the availability of a high-throughput platform that facilitates the rapid assessment of vaccine immunogenicity and reactogenicity. Given that these vaccine properties commonly originate from vaccine-elicited immune responses, it is imperative to gain a comprehensive understanding of vaccine immunity from multiple perspectives and at sufficient depths. In response to the challenges posed by the COVID-19 pandemic, cutting-edge technologies have been introduced to profile the immune system at both molecular and cellular levels. These advancements provide crucial insights into the dynamics of the immune system and identify molecular/cellular targets for innovative evaluation systems. This presentation highlights the potential of immune profiling, showing examples from COVID-19 and other vaccines to illustrate the impact and possibilities of these advancements.

In the mucosa, IgA antibodies are secreted as multimeric antibodies, which play important roles in normal flora control as well as in infection control. In contrast to IgG antibodies, which are predominantly specific for a single antigen, these mucosal IgA antibodies are known to be broadly antigen-specific, allowing a single type of antibody to respond to multiple antigens.

For SARS-CoV2, it has been shown that multimeric IgM and IgA antibodies can cope with more variants than IgG antibodies. Thus, the development of an effective mucosal vaccine adjuvant that induces mucosal polymeric IgA antibodies provides strong mucosal protection against bacterial and viral infections. This is very different from the conventional vaccine that stimulates the increase of antibody in the serum by intramuscular injection and targets the pathogen after invasion into the body. We believe that it is important for B cells activated by antigens to efficiently migrate to germinal centers in order to induce high-affinity antibodies on mucosal surfaces. We have therefore found a marker for pre-germinal center B cells and are conducting research on substances that induce this marker as novel mucosal vaccine adjuvants. We discuss the evaluation of mucosal immunity of vaccine adjuvants based on intestinal germinal center B cell responses.

By experiencing the COVID-19 pandemic, we researchers have learned a lot about infectious disease control. At a time when there is an urgent need to build a system to prepare for the next possible infectious disease pandemic, life science research is at a major turning point. Building a new research system to prepare for emerging and reemerging infectious diseases will depend on how quickly and smoothly we can switch research styles between normal and emergency situations and how efficiently we can gather the effort of researchers. The AMED BINDS project is the operation of a platform where groups of researchers with world-class technologies and facilities support life science researches and drug discovery in Japan during ordinary times. This network of BINDS researchers can also be a powerful aid in accelerating the development of vaccines and therapeutics in emergency situations. This presentation will introduce the ideal platform concept for emergency situations that would be possible with SCARDA and BINDS working together, as well as the actual good cooperation that has been achieved for M pox.

In the early 1990s, the amyloid cascade hypothesis was proposed based on genetic research into familial Alzheimer's disease (AD) as the mechanism of AD onset and progression. Subsequently, numerous clinical trials of agents based on this hypothesis were conducted, leading to many failures. However, these research results contributed to 1) the identification of toxic species, 2) the selection of the appropriate subject population, 3) the logical determination of dosages and administration durations based on biomarkers, and 4) the development of highly sensitive primary endpoints. This presentation provides an overview of the history of anti-Aβ drug development, non-clinical research on mechanisms of action, and clinical trial results, including biomarkers. It also outlines the prospects for future Alzheimer's disease drug development.

Disease-modifying anti-amyloid antibodies for Alzheimer's disease (AD) were approved in Japan this year and hold the promise of being included under healthcare coverage. The treatment of dementia is now at a major turning point.

Imaging technology for neurodegeneration has entered the era of proteinopathy imaging, starting with amyloid PET. Meanwhile, technological developments have made it possible to image tau lesions by tau PET, and prenatal diagnosis of tauopathy is improving dramatically.

In our cohort study, we performed amyloid and tau PET and compared changes in diagnosis, treatment, and management before and after PET. The results showed that the results of the two PETs changed the diagnosis of dementia by 35% and the treatment and management by 30%. (Shimohama S., 2022) In addition, we compared various blood biomarkers using highly reliable plasma samples obtained in the above study. As a result, we found that the HISCL amyloid-β42/40 ratio had high diagnostic accuracy (AUC:0.950). (Bun S., 2023) Furthermore, we were able to construct a predictive model of AD pathology with extremely high accuracy (AUC=0.994) based on comprehensive proteomics (3000 protein quantifications) using machine learning. This inexpensive and non-invasive blood biomarker can be a powerful tool for the upcoming introduction of dementia disease-modifying drugs.

In this talk, I will outline the prospects for AD disease-modifying drugs and the current status of protinopathy imaging and fluid biomarkers, and discuss the next-generation dementia treatment system.

The approval of Lecanemab, a monoclonal antibody that targets amyloid-β (Aβ) aggregates, marks a major milestone in drug discovery research for Alzheimer disease (AD). It confirms that Aβ is a key molecular driver of AD pathogenesis and a valid therapeutic target. However, it has also been shown that clearing Aβ aggregates from the brain does not fully stop the progression of AD. Therefore, new approaches are needed in addition to anti-Aβ antibodies. One promising avenue is targeting aggregated tau, another pathological hallmark of AD that is directly linked to neurodegeneration. Moreover, large-scale observational studies and clinical trials with anti-Aβ antibodies, as well as advances in biomarker development, have revealed the potential role of glial cells as a new target for drug discovery. Furthermore, drug discovery strategies for patients with advanced neurodegeneration are still lacking. In this presentation, I will summarize the current status and future challenges of AD drug discovery.

This presentation introduces efforts in predicting novel drug target genes using gene network analysis powered by Fugaku. While gene network analysis has traditionally been conducted, it has not sufficiently considered the variability in individual patients' responses to drugs and pathogens. Although AI-based methods are often evaluated solely on their predictive capabilities, this study expands on the concept of explainable AI using Bayesian networks. Leveraging Fugaku's computational power, we present an approach to explore novel drug candidate genes in a manner comprehensible to humans.

The demand for AI in drug discovery has been increasing, and various AI application prototypes have been developed to optimize the drug development process. However, unfortunately, these AI applications are not yet widely used in pharmaceutical companies' drug discovery efforts. One of the reasons for this is the decentralized nature of individual applications and the lack of an integrated platform. In the current state, researchers cannot easily utilize applications when needed.

To address this issue, we have incorporated approximately 20 AI and analytical technology applications we have developed into an integrated platform in a common computing infrastructure centered around the Supercomputer “Fugaku.” This platform is designed to construct workflows for drug target discovery, estimating target proteins. Specifically, we have incorporated information technologies like Graph Convolutional Networks and Bayesian Networks, which can predict candidate drug target molecules from large-scale biomedical data, including clinical data, omics data, and literature data. Ultimately, this platform allows the input of disease names, patient sample data, and more, enabling the estimation of disease mechanisms and target proteins using an HPC/AI workflow.

.In the early stage of drug development, high-throughput screening is carried out using experimental assays. It is currently estimated that there are over 10⁶³ potential compounds as drug candidates. Consequently, there has been growing interest in virtual drug screening as a cost-effective and time-efficient approach. Virtual screening methods can be divided into two types: an AI-based approach, which leverages machine learning models trained on existing experimental data, and a docking simulation, which is based on three-dimensional structures of target proteins. Whereas various techniques have been proposed in both approaches, a significant gap still exists in the virtual and real-world scenarios, such as imbalanced data and dynamics properties of molecules. In this presentation, we will introduce our efforts in practical evaluation of protein-compound evaluation in both the AI-based and the structure-based approaches. In the former, we have improved the model's generalizability with self-training method to address the lack of experimentally validated negative samples in the public databases. In the latter, we have successfully achieved molecular dynamics-based protein-drug screening by utilizing the supercomputer Fugaku. These achievements represent significant advances in next-generation computer-assisted drug discovery.

Epigenomes allow the rectification of disordered cancer gene expressions. This is the first study to illustrate patients’ molecular and cellular dynamics in response to an inhibitor designed for histone methyltransferase. We recently found the potency and mechanisms of action and resistance of an EZH1/2 dual inhibitor valemetostat in the clinical trials of patients with adult T-cell leukemia/lymphoma (ATL). Valemetostat administration reduced the tumor size and demonstrated durable clinical benefits. Integration of the intensive multilayered single-cell omics platform and clinical resources revealed that valemetostat abolished histone H3K27me3-mediated highly condensed chromatin and neutralized multiple gene loci, including tumor suppressor genes. Eliminating H3K27me3 led to reprogramming the cancer epigenome, thereby exerting a sustained benefit on tumors. Furthermore, both treatment-naive and treatment-adapted patients displayed the characteristic condensed chromatin structures, consistently suggesting that chromatin compaction is indispensable for tumor maintenance and growth. We hope that targeting the new concept “chromatin homeostasis” can provide a new avenue of vast opportunities for durable cancer treatment.

Mechanisms underpinning the dysfunctional immune response in SARS-CoV-2 infection are not yet fully understood. In addition, the functional roles of the genetic variants identified by COVID-19 genome-wide association study (GWAS) remain elusive, especially in non-European ancestry. We analyzed single-cell transcriptomes and T and B cell receptors of > 895,000 peripheral blood mononuclear cells from 73 COVID-19 patients and 75 healthy controls of Japanese ancestry with host genetic data. COVID-19 patients showed a low fraction of nonclassical monocytes (ncMono). We report downregulated cell transitions from classical monocytes to ncMono in COVID-19 with reduced CXCL10 expression in ncMono in severe disease. Cell-cell communication analysis inferred decreased cellular interactions involving ncMono in severe COVID-19, suggesting that the dysfunction of ncMono might be closely involved in the immunopathology of COVID-19 severity.  Clonal expansions of B cell receptors were evident in plasmablasts of patients. Putative disease genes identified by the GWAS of severe phenotypes showed cell type-specific expressions in monocytes and dendritic cells. A COVID-19-associated risk variant at the IFNAR2 locus (rs13050728) had COVID-19-specific and monocyte-specific expression quantitative trait loci effects, indicating the enrichment of host genetic risk in innate immune cells. Our multimodal and integrative single-cell analyses highlight biological and host genetic involvement of innate immune cells in COVID-19 severity.

Cardiovascular disease is a leading cause of death worldwide. Because adult cardiomyocytes (CMs) have a low regenerative capacity, damaged CMs are replaced by cardiac fibroblasts (CFs) after myocardial infarction (MI), leading to loss of contractile function of the heart and eventually to heart failure. There are no treatments available to regenerate myocardium and reverse fibrosis in MI. Direct cardiac reprogramming may be a promising approach for both cardiac regeneration and antifibrotic therapy. Overexpression of cardiac transcription factors, including Mef2c, Gata4, Tbx5, and Hand2 (MGTH), directly reprograms a subset of CFs into induced cardiomyocytes (iCMs) in vivo and vitro. Recently, we found that in vivo cardiac reprogramming generates new iCMs from resident CFs, improves cardiac function, and reduces fibrosis in chronic MI in mice. Single-cell RNA sequencing (scRNA-seq) demonstrated that in vivo cardiac reprogramming altered the interstitial cell landscape in chronic MI. In addition, scRNA-seq revealed that overexpression of MGTH in CFs not only induced iCMs, but also suppressed fibroblast gene signatures through the conversion of profibrotic CFs to a quiescent antifibrotic state. These findings suggest that in vivo cardiac reprogramming may become a pioneering therapy for chronic HF by regenerating cardiomyocytes and reducing fibrosis.

Cellular senescence is observed in various kinds of cells as a result of repeating proliferation or exposure to various genotoxic stresses. It is also known that senescent cells can accumulate in organs as aging and become a substrate of age-related disorders. A novel therapeutic strategy that eliminates senescent cells specifically from the body, so-called “lysis of senescent cells (senolysis)” has been demonstrated to ameliorate various age-related diseases and extend the lifespan of mammals without increasing cancer incidence. Our group has recently identified senescence-associated molecules through omics studies and developed “senolytic vaccine” targeting Glycoprotein nonmetastatic melanoma protein B (GPNMB) as an antigen upregulated in senescent endothelial cells. GPNMB-vaccine could exhibit senolysis leading to amelioration of atherosclerosis and diabetes as well as aged-phenotype in mice.

In our latest work, we have conducted single-cell analysis in senescent cells, which clarified the diversity of senescent cells and enabled more precise identification of senescence-associated molecules. The single-cell analysis-driven approach would be promising for understanding the nature of senescent cells as well as the efficient development of therapeutics targeting them.

As the brain has a high degree of functional specialization and is highlyintegrated at various hierarchies, it is necessary to investigate anatomical andfunctional brain networks unbiasedly and independently of any foreseenhypothesis to elucidate the pathophysiology of brain diseases. To address theissue, we have developed a highly scalable and high-speed imaging system(block-FAce Serial microscopy Tomography, FAST) and methods to comparestructures and neural activity among individual animal groups. Using thesemethods, we are examining anatomical structure and neuronal activity changes inanimal disease models and those administered with therapeutic drugs. In thissymposium, I will introduce our recent progress and discuss the directions offuture research that would contribute to a better understanding of brain systemsand disorders.

Addiction is defined as a psychic state of patients characterized by psychobehavioral changes such as compulsions to take a drug and reinforcing behaviors, even they know its side effects. It is difficult to prevent relapse of addiction in the present. In terms of drug dependence, it is urgent issue to investigate molecular and neurocircuit associated with drug-seeking behavior and therapeutic strategies. The formation of enduring associations between the primary rewarding properties of drugs and the environmental cues linked to drug use produces powerful triggers for relapse in abstinent addicts. The persistence of craving and high incidence of relapse following prolonged periods of abstinence in the addicted patient population is a major hurdle for therapeutic treatments. However, it remains unclear the molecular mechanism by which addictive drugs lead drug-seeking behaviors, due to the delay in technological development. We have recently developed novel comprehensive phosphoproteomic analysis and database that enables us to understand phosphorylation signal. In this symposium, I will discuss the signaling pathway in accumbal neurons using our phosphoproteomics in order to elucidate the molecular mechanism to induce drug-seeking behavior signal. I also propose the novel direction to treat addiction.

Microglia have a high capacity to repopulate in the adult brain. Microglial survival requires signaling via the colony-stimulating factor 1 receptor (CSF1R), and the removal/repopulation of microglia can be triggered by turning ON/OFF of CSF1R antagonists. Using this microglial replacement protocol ("reset"), we show its therapeutic effect on Alexander disease (AxD). AxD is a primary astrocytic disease caused by mutations in GFAP, but microglial activation occurs in the AxD brain as well. It is well known that many neurodegenerative and psychiatric diseases are accompanied by microglial activation, leading to neuroinflammation. Therefore, removal of microglia is considered one of the strategies for the treatment of these diseases. However, we found that microglial removal with CSF1R antagonists exersavated AxD pathology. This suggests that microglia, or at least some populations of them, play a beneficial role in AxD pathology. We found that reset, but not elimination of microglia ameliorated AxD pathology. Thus, we suggest that microglial replacement may be a better therapeutic strategy for AxD and possibly for other neurological diseases. We also report on the mechanisms underlying the therapeutic effect via microglial reset by RNAseq analysis.

We have performed a multi-scale synaptic analysis of mouse models of psychiatric disorders and found some candidate phenomena for the pathophysiology of the disorders. However, mouse models alone will not be sufficient to elucidate human psychiatric disorders. I believe that the combinatorial use of human-derived neurons, theoretical neuroscience and reverse translational feedback to mouse research is key. Human-derived samples include post-mortem brains, human iPSC-derived neurons and neurosurgically removed acute brain samples. While such human data can provide invaluable insights, they do not by themselves lead to an understanding of human disease. Therefore, to bridge the gap between the obtained "human data" and "our questions", we also use computational methods and integrate the human data into mathematical models, specifically the NEURON model, the Leaky Integrate-and-Fire model and the Free Energy model, and construct neuronal, circuit and behavioural models that implement the human parameters. In the talk I will present our current challenge of a rapid circulation between mouse, human and theoretical neuroscience to understand human psychiatric disorders.

Stress is a physical and mental strain caused by aversive and demanding conditions and risks mental illnesses, including depression and dementia. Rodent studies using stress models have shown that acute stress increases dendritic growth of prefrontal neurons and stress resilience via dopamine, whereas chronic stress activates microglia via the innate immune receptors TLR2/4, leading to neuronal and behavioral dysfunction. Chronic stress also promotes behavioral dysfunction by mobilizing leukocytes from the bone marrow. Thus, the role of inflammation in the brain and periphery in stress-induced neural dysfunction has been established. However, as our understanding of the biological basis of stress is still fragmentary, we and others are using single-cell omics and multi-omics analyses and molecular manipulations in a manner selective for brain regions and cell types to comprehensively identify the biological basis of stress-induced inflammation in the brain and periphery and link it to multiple behavioral domains. In this talk, I will present our recent findings on stress-induced inflammation and its relevance to neural dysfunction and discuss their implications for a cross-disease understanding of mental illnesses.

The central nervous system (CNS) hosts a variety of immune cells including two anatomically and transcriptionally distinct macrophage populations: microglia are found in the parenchyma, whereas CNS border-associated macrophages (CAMs) cover the CNS interfaces, such as the perivascular spaces and the meninges. Recent emergence of novel genetic tools and cutting-edge techniques including single-cell RNA-seq enables to study the CNS macrophages in more depth and have given novel insights into the origins, kinetics, functions, transcriptomic profiles, heterogeneity of microglia and CAMs. In this symposium, I will discuss our current knowledge of the characteristics of CNS macrophages.

In the brain, peripheral immune cells are localized in specific regions such as meningeal space, choroid plexus, and perivascular spaces, and contribute to brain development. Previous cohort studies have shown that meningeal inflammation during neonatal periods is a potent risk factor for neurodevelopmental disorders such as attention-deficit hyperactivity disorders (ADHD), however, the pathological mechanism underlying neonatal meningeal inflammation-induced neurodevelopmental disorders has been still unclear. To elucidate the pathological mechanism of neurodevelopmental disorders caused by neonatal meningeal inflammation, we induced meningeal inflammation in neonatal mice, and found that neonatal meningeal inflammation-induced mice exhibited ADHD-like behaviors in adulthood. Histological analysis and adeno-associated virus-based neurotracing or pharmacogenetics showed increased dopaminergic inputs in the nucleus accumbens (NAc) was responsible for ADHD-like behaviors. Moreover, a large number of inflammatory macrophages was observed in the brain after inducing meningeal inflammation, and macrophage depletion inhibited ADHD-like behaviors. These results demonstrated that ADHD-like behaviors after neonatal meningeal inflammation is caused by the formation of aberrant dopaminergic synapses in NAc by inflammatory macrophages.

Neuron-associated macrophages, shortly NAMs, are one of macrophage subsets which exists on peripheral neurons. NAMs have been identified in various organs including the intestine, skin, lung and adipose tissues. NAMs are responsible for maintaining the tissue integrity through protecting neurons and regulating the immune system. We also newly found out a NAM subset in the liver, especially on the portal vein. The portal vein is the most pivotal feeding vessel which transports food-derived nutrients from the gastrointestinal tract to the liver. Periportal NAM (pNAM) may be responsible for maintaining this vascular homeostasis and controlling the nutrient supply, however, the physiological functions remain uncovered. 

To reveal detailed molecular expressions of pNAM, we performed single-cell RNA sequencing and succeeded in identifying the pNAM cluster and its marker molecules. Estimation of physiological functions using differentially expressed genes in pNAM indicated a possibility that pNAM senses intravascular substances. To directly demonstrate this function, we established an intravital multiphoton imaging system for the portal vein. As the result, we successfully visualized uptake of intravascular substances by pNAM. We are currently investigating what happens in neurons after pNAM senses intravascular substances. Our final goal is to elucidate the importance of pNAM-neuron interactions in liver and portal vein function.

Nicotinamide adenine dinucleotide (NAD⁺) is an essential co-factor mediating numerous redox reactions. NAD⁺ is consumed as a substrate for poly(ADP-ribose) polymerase (PARP) and sirtuins and regulates various biological processes, such as metabolism, DNA repair, gene expression, and stress responses. In living organisms, the NAD⁺ levels are determined by a balance between NAD⁺ production and degradation. Recently, numbers of studies have demonstrated that NAD⁺ levels decline with age, and the deterioration of NAD⁺ metabolism promotes aging and aging-associated diseases, including metabolic diseases, neurodegenerative disease, and musculoskeletal diseases. Contrariwise, elevated NAD⁺ levels in tissue exhibit beneficial effects in both physiological and pathological aging. Various approaches, such as supplementation with NAD⁺ precursors, activation of NAD⁺ biosynthetic pathways, and inhibition of NAD⁺ degradation, have been used to increase NAD⁺ levels. In this presentation, I will show the recent progress regarding the role of NAD⁺ metabolism in aging and discuss the possibilities of NAD⁺ metabolism as a therapeutic target against aging