Biology subjects

Hayashi, K.

Publications and source records attributed to Hayashi, K..

At least 55 records · Page 3Linked to original sources

bioRxiv2023

Propagation of neuronal micronuclei regulates microglial states

Microglia, resident immune cells in the central nervous system, undergo morphological and functional changes in response to signals from the local environment and mature into various homeostatic states. However, niche signals underlying microglial development and maturation remain largely unknown. In this study, we show that neuronal micronuclei propagate microglia, followed by changing microglial states during the postnatal period. We discovered that neurons passing through a dense region of the developing neocortex give rise to micronuclei and release them into the extracellular space. Moreover, neuronal micronuclei were incorporated into microglia and affected morphological changes. Loss of the cGAS gene alleviates effects on micronucleus-dependent morphological changes. Notably, neuronal micronuclei-harboring microglia exhibit unique transcriptome signatures. These results demonstrate that neuronal micronuclei serve as niche signals that produce novel microglial states. Our findings provide a potential mechanism for regulating the microglial state in the early-postnatal neocortex.

neuroscience↗

bioRxiv2023

The highly developed symbiotic system between the solar-powered nudibranch Pteraeolidia semperi and Symbiodiniacean algae

The intricate coexistence of Symbiodiniacean algae with a diverse range of marine invertebrates underpins the flourishing biodiversity observed within coral reef ecosystems. However, the phenomenon of coral bleaching--precipitated by the dissolution of symbiotic relationships with Symbiodiniaceae--poses a significant threat to these ecosystems, thereby necessitating an urgent investigation into the underlying symbiotic mechanisms. The symbiosis between nudibranchs and Symbiodiniaceae has been identified as an efficacious model for examining these mechanisms, yet a comprehensive understanding of their histological structures and cellular processes remains elusive. In this study, we concentrate on the nudibranch host Pteraeolidia semperi, renowned for its exceptional symbiotic capabilities, and we elucidate its sophisticated symbiotic architecture. Furthermore, we delineate the bleaching process within the nudibranch, uncovering the associated cellular processes. Collectively, these findings furnish invaluable insights into the intricate relationship between nudibranchs and Symbiodiniaceae, thereby contributing to our understanding of the symbiosis that sustains these critical marine ecosystems.

cell biology↗

bioRxiv2023

The complete mitochondrial genome of Spurilla braziliana MacFarland 1909 (Nudibranchia, Aeolidiidae).

Spurilla braziliana MacFarland 1909 is a morphologically diverse nudibranch found in the Pacific and Western Atlantic. The complete mitochondrial genome of S. braziliana has been constructed using next-generation sequencing technology. The mitochondrial genome is 14,291 bp and contains 13 protein-coding genes, 2 rRNA genes, and 23 tRNA genes. Molecular phylogenetic analysis using the maximum likelihood method revealed that S. braziliana is included in the superfamily Aeolidioidea and forms a monophyletic group with Berghia stephanieae, a nudibranch of the family Aeolidiidae. This study reinforces existing taxonomic insights and provides a basis for further molecular phylogenetic analysis.

genomics↗

bioRxiv2023

Virtual screening of antimicrobial plant extracts by machine-learning classification of chemical compounds in semantic space

Plant extract is a mixture of diverse phytochemicals, and considered as an important resource for drug discovery. However, large-scale exploration of the bioactive extracts has been hindered by various obstacles until now. In this research, we have introduced and evaluated a new computational screening strategy that classifies bioactive compounds and plants in semantic space generated by word embedding algorithm. The classifier showed good performance in binary (presence/absence of bioactivity) classification for both compounds and plant genera. Furthermore, the strategy led to the discovery of antimicrobial activity of essential oils from Lindera triloba and Cinnamomum sieboldii against Staphylococcus aureus. The results of this study indicate that machine-learning classification in semantic space can be a highly efficient approach for exploring bioactive plant extracts.

bioinformatics↗

bioRxiv2022

The impact of sex and physical activity on the local immune response to muscle pain

Induction of muscle pain triggers a local immune response to produce pain and this mechanism may be sex and activity level dependent. The purpose of this study was to measure the immune system response in the muscle following induction of pain in sedentary and physically active mice. Muscle pain was produced via an activity-induced pain model using acidic saline combined with fatiguing muscle contractions. Prior to induction of muscle pain, mice (C57/BL6) were sedentary or physically active (24hr access to running wheel) for 8 weeks. The ipsilateral gastrocnemius was harvested 24hr after induction of muscle pain for RNA sequencing or flow cytometry. RNA sequencing revealed activation of several immune pathways in both sexes after induction of muscle pain, and these pathways were attenuated in physically active females. Uniquely in females, the antigen processing and presentation pathway with MHC II signaling was activated after induction of muscle pain; activation of this pathway was blocked by physical activity. Blockade of MHC II attenuated development of muscle hyperalgesia exclusively in females. Induction of muscle pain increased the number of macrophages and T-cells in the muscle in both sexes, measured by flow cytometry. In both sexes, the phenotype of macrophages shifted toward a pro-inflammatory state after induction of muscle pain in sedentary mice (M1+M1/2) but toward an anti-inflammatory state in physically active mice (M2+M0). Thus, induction of muscle pain activates the immune system with sex-specific differences in the transcriptome while physical activity attenuates immune response in females and alters macrophage phenotype in both sexes.

immunology↗

bioRxiv2022

Megacolonies: an alternative social organization in anemonefishes?

Anemonefish are iconic examples of marine fishes living in mutualistic symbiosis with sea anemones. In a given sea anemone, the anemonefishes have a stereotyped social organization with a dominant female, a semi-dominant male, and several juveniles. A strict size-based hierarchy governs the social interactions within these colonies, with each individual differing from the previous or next fish in the order by +/- 20% size. This social organization is conserved across the Indo-Pacific in all 28 species of anemonefish found on any of ten giant sea anemone species. We report the existence of huge "megacolonies" of up to 100 fish living in large carpets of sea anemones. This alternative organization was observed for different fish and anemone species in different coral reef locations (French Polynesia, Japan, Taiwan, and Vietnam). In these colonies, the strict size-based hierarchy is no longer recognizable, and the level of aggressivity of the different members appears lower than in "normal" colonies. These megacolonies may correspond to a previously overlooked type of social organization that could be linked to host availability and offer a unique opportunity to understand anemonefishs behavioral, social, and hormonal plasticity.

ecology↗

bioRxiv2022

A stem cell zoo uncovers intracellular scaling of developmental tempo across mammals

Differential speeds in biochemical reactions have been proposed to be responsible for the differences in developmental tempo between mice and humans. However, the underlying mechanism controlling the species-specific kinetics remains to be determined. Using in vitro differentiation of pluripotent stem cells, we recapitulated the segmentation clocks of diverse mammalian species varying in body weight and taxa: marmoset, rabbit, cattle and rhinoceros. Together with the mouse and human, the segmentation clock periods of the six species did not scale with the animal body weight, but were rather grouped according to phylogeny. The biochemical kinetics of the core clock gene HES7 displayed clear scaling with the species-specific segmentation clock period. However, the cellular metabolic rates did not show an evident correlation. Instead, genes involving biochemical reactions showed an expression pattern that scales with the segmentation clock period. Altogether, our stem cell zoo uncovered general scaling laws governing species-specific developmental tempo.*

developmental biology↗

bioRxiv2022

An attenuated vaccinia vaccine encoding the SARS-CoV-2 spike protein elicits broad and durable immune responses, and protects cynomolgus macaques and human ACE2 transgenic mice from SARS-CoV-2 and its variants

As long as the coronavirus disease 2019 (COVID-19) pandemic continues, new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with altered antigenicity will emerge. The development of vaccines that elicit robust, broad, and durable protection against SARS-CoV-2 variants is urgently needed. We have developed a vaccine (rDIs-S) consisting of the attenuated vaccinia virus DIs strain platform carrying the SARS-CoV-2 S gene. rDIs-S induced neutralizing antibody and T-lymphocyte responses in cynomolgus macaques and human angiotensin converting enzyme 2 (hACE2) transgenic mice, and showed broad protection against SARS-CoV-2 isolates ranging from the early-pandemic strain (WK-521) to the recent Omicron BA. 1 variant (TY38-839). Using a tandem mass tag (TMT) -based quantitative proteomic analysis of lung homogenates from hACE2 transgenic mice, we found that, among mice subjected to challenge infection with WK-521, vaccination with rDIs-S prevented protein expression related to the severe pathogenic effects of SARS-CoV-2 infection (tissue destruction, inflammation, coagulation, fibrosis, and angiogenesis) and restored protein expression related to immune responses (antigen presentation and cellular response to stress). Furthermore, long-term studies in mice showed that rDIs-S maintains S protein-specific antibody titers for at least 6 months after a 1st vaccination. Thus, rDIs-S appears to provide broad and durable protective immunity against SARS-CoV-2, including current and possibly future variants.

microbiology↗

bioRxiv2022

Machine-Learning-Based Olfactometry: Odor Descriptor Clustering Analysis for Olfactory Perception Prediction of Odorant Molecules

Although gas chromatography/olfactometry (GC/O) has been employed as a powerful analytical tool in odor measurement, its application is limited by the variability, subjectivity, and high cost of the trained panelists who are used as detectors in the system. The advancements in data-driven science have made it possible to predict structure-odor-relationship (SOR) and thus to develop machine-learning-based olfactometry (ML-GCO) in which the human panelists may be replaced by machine learning models to obtain the sensory information of GC-separated chemical compounds. However, one challenge remained in ML-GCO is that there are too many odor descriptors (ODs) being used to describe the sensory characteristics of odorants. It is impractical to build a corresponding model for each OD. To solve this issue, we propose a SOR prediction approach based on odor descriptor clustering. 256 representative ODs are firstly classified into 20 categories using a co-occurrence Bayesian embedding model. The categorization effect is explained according to the semantic relationships using a pre-trained Word2Vec model. Various molecular structure features including molecularly parameters, molecular fingerprints, and molecular 2D graphic features extracted by convolutional neural networks, are employed to predict the aforementioned odor categories. High prediction accuracies (Area under ROC curve was 0.800{+/-}0.004) demonstrate the rationality of the proposed clustering scenario and molecular feature extraction. This study makes the ML-GCO models much closer to the practical application since they can be expected as either an auxiliary system or complete replacement of human panelists to perform the olfactory evaluation.

molecular biology↗

bioRxiv2022

Odorant molecular feature mining by diverse deep neural networks for prediction of odor perception categories

The use of an artificial intelligence (AI)-based prediction model of the structure-odor relationship (SOR) has shown great potential in the replacement of human panelists in gas chromatography-olfactometry (GCO). However, the Al-based GCO encounters issues such as poor accuracy, generalization, and practicality, owning to the insufficient feature extraction of odorant molecular structure. The purpose of this study is to the prediction of odor perception categories based on the odorant structure feature extraction by diverse deep neural networks, including molecular graphic convolution neural network (MG-CNN), molecular graph transformer neural network, and atom interaction neural networks. The results of the performance comparison of different feature extractors demonstrate that the MG-CNN model produces the highest accuracy and thus may be most suitable for the SOR prediction. It is hoped that the proposed method can be applied in practice as an auxiliary tool of GCO for the sensory evaluation of key compounds in food ingredients. HighlightsO_LIDifferent deep neural networks were used to predict categorized odor descriptors. C_LIO_LIEnd-to-end-based representation learning was performed for molecular feature extraction. C_LIO_LIMolecular graphs with pre-training of convolution neural networks was most accurate. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=82 SRC="FIGDIR/small/488977v2_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@10495a2org.highwire.dtl.DTLVardef@1fbf27eorg.highwire.dtl.DTLVardef@1ed3664org.highwire.dtl.DTLVardef@8e1383_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

bioRxiv2022

Niclosamide targets macrophages to rescue the disrupted peritoneal homeostasis in endometriosis

Due to the vital roles of macrophages in the pathogenesis of endometriosis, targeting macrophages could be a new therapeutic direction. Here, we investigated the efficacy of niclosamide for the resolution of perturbed microenvironment caused by dysregulated macrophages in a mouse model of endometriosis. Single-cell transcriptomic analysis revealed the heterogeneity of macrophage subpopulations including three newly identified intermediate subtypes with sharing characteristics of traditional "small" or "large" peritoneal macrophages (SPMs and LPMs) in the peritoneal cavity. Endometriosis-like lesions (ELL) enhanced the differentiation of recruited macrophages, promoted the replenishment of resident LPMs, and increased ablation of embryo-derived LPMs, which were stepwise suppressed by niclosamide. In addition, niclosamide reversed intercellular communications between macrophages and B cells which were disrupted by ELL. Therefore, niclosamide rescued the perturbed microenvironment in endometriosis through its fine regulations on the dynamic progression of macrophages and could be a new promising therapy for endometriosis. SummaryNiclosamide tunes the dynamic progression of peritoneal macrophages and their intercellular communications with B cells to rescue the disrupted microenvironment in the peritoneal cavity in a mouse model of endometriosis. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=155 SRC="FIGDIR/small/487220v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@e6700eorg.highwire.dtl.DTLVardef@c6c557org.highwire.dtl.DTLVardef@1c60b92org.highwire.dtl.DTLVardef@121bce6_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphic AbstractC_FLOATNO C_FIG

molecular biology↗

bioRxiv2021

Extreme value analysis of intracellular cargo transport by motor proteins

Extreme-value analysis (EVA) deals with deviations in the data from the median of the probability distributions. EVA serves various purposes such as predicting disasters and analyzing sports records. Herein, we extended the use of EVA to investigate the motility functions of nanoscale motor proteins in neurons of the living worm Caenorhabditis elegans (C. elegans). Motor proteins, such as kinesin and dynein, move along microtubules anterogradely and retrogradely, respectively, to deliver the cargo-containing materials needed for the cells. Although the essential difference between the two motors could not be inferred from the mean velocity values, the return-level EVA plots obtained from the velocity data revealed a difference. Shape parameters of the generalized extreme value distribution of EVA{xi} < 0 for anterograde transport and{xi} [≥] 0 for retrograde transport. Our findings extend the possibility and applicability of EVA for analyzing motility data of nanoscale proteins in vivo.

biophysics↗

bioRxiv2021

Intracellular force comparison of pathogenic KIF1A, KIF5, and dynein by fluctuation analysis

In mammalian cells, there exist approximately 40 types of microtubule motor proteins that are assigned to specific cargo deliveries. For example, the kinesin-1 family motor KIF5 is the major motor responsible for anterograde mitochondrial transport, whereas the kinesin-3 family motor KIF1A is responsible for synaptic vesicle precursor transport. In contrast, cytoplasmic dynein is responsible for retrograde transport of nearly all cargos. The force and velocity of these microtubule motors have been investigated in in-vitro single-molecule experiments. In the present study, we compared the intracellular force and velocity of various types of motors in the mammalian neuronal axon obtained by non-invasive force measurement (fluctuation analysis) and extreme value analysis with those obtained by previous single-molecule experiments. As we found a high correlation between our results and the previous results, we next investigated synaptic vesicle precursor transport by hereditary spastic paraplegia-associated KIF1A variants (V8M, R350G, and A255V). KIF1A-V8M and KIF1A-A255V exhibited force and velocity impairment in mammalian neuronal axons, whereas the physical property of KIF1A-R350G was similar to that of the wild type. We believe that the development of new analytical techniques for investigating intracellular cargo transports is helpful to elucidate the molecular mechanism of KIF1A-associated neurological disorders. Statement of SignificanceRecent in-vitro single-molecule experiments have clearly revealed that microtubule motors only fully exert their functions when fully equipped with the proteins associated with cargo vesicle transport. This emphasizes the significance of intracellular physical measurements, in which the motors should fully function. In addition to motor force and velocity, the number of motors transporting a single cargo together is an important physical quantity to characterize cargo transport, but is difficult to estimate using in-vitro single-molecule experiments. In this study, we aimed to extract physical information on microtubule motors in the intracellular environment.

biophysics↗

bioRxiv2021

Vapor cannabis exposure generationally affects male reproductive functions in mice

This study was performed to examine whether vapor exposure to cannabis plant matter negatively impacts male reproductive functions and testis development in mice. Adult CD-1 male mice (F0) were exposed to air (control) or 200 mg of vaporized cannabis plant matter 3x/day over a 10 day period. Subsequently, F0 males were bred with drug naive CD-1 females to generate F1 males, and F1 offspring were used to generate F2 males. Cannabis vapor exposure decreased sperm count and/or motility in F0 and F1 males and disrupted the progression of germ cell development, as morphometric analyses exhibited an abnormal distribution of the stages of spermatogenesis in F0 males. Although plasma levels of testosterone were not affected by cannabis exposure in any ages or generations of males, dysregulated steroidogenic enzymes, Cyp11a1 and Cyp19a1, were observed in F0 testis. In the neonatal testis from F1 males, while apoptosis was not altered, DNA damage and DNMT1, but not DNMT3A and DNMT3B, were increased in germ cells following cannabis exposure. In contrast, the alterations of DNA damage and DNMT1 expression were not observed in F2 neonatal males. These results suggest that cannabis vapor exposure generationally affects male reproductive functions, probably due to disruption of spermatogenesis in the developing testis. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=156 SRC="FIGDIR/small/457271v1_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@1a6782borg.highwire.dtl.DTLVardef@1b5e42org.highwire.dtl.DTLVardef@c94d78org.highwire.dtl.DTLVardef@1fd269d_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSO_LICannabis vapor exposure to adult males impairs sperm counts, motility and spermatogenesis. C_LIO_LICannabis vapor exposure to F0 males causes reduced sperm counts in F1, but not in F2 males. C_LIO_LIPlasma testosterone levels are not affected in F0, F1 and F2 males by cannabis exposure. C_LIO_LICannabis increases DNA damage and the expression of DNA methyltransferase (DNMT) 1 in the F1 neonatal testis. C_LI

pharmacology and toxicology↗

bioRxiv2021

A temporally controlled sequence of X-chromosomeinactivation and reactivation defines female mouse in vitro germ cells with meiotic potential

The early mammalian germ cell lineage is characterized by extensive epigenetic reprogramming, which is required for the maturation into functional eggs and sperm. In particular, the epigenome needs to be reset before parental marks can be established and then transmitted to the next generation. In the female germ line, reactivation of the inactive X-chromosome is one of the most prominent epigenetic reprogramming events, and despite its scale involving an entire chromosome affecting hundreds of genes, very little is known about its kinetics and biological function. Here we investigate X-chromosome inactivation and reactivation dynamics by employing a tailor-made in vitro system to visualize the X-status during differentiation of primordial germ cell-like cells (PGCLCs) from female mouse embryonic stem cells (ESCs). We find that the degree of X-inactivation in PGCLCs is moderate when compared to somatic cells and characterized by a large number of genes escaping full inactivation. Nevertheless, PGCLCs that fail to undergo X-inactivation show an abnormal gene expression signature and deficiencies in meiotic entry. Subsequent to X-inactivation we observe gradual step-wise X-reactivation, which is mostly completed by the end of meiotic prophase I. Cells deviating from these progressive kinetics and undergoing X-reactivation too rapidly fail to enter a meiotic trajectory. Our data reveals that a fine-tuned X-inactivation and -reactivation cycle is a critical feature of female germ cell developmental competence towards meiosis and oogenesis

developmental biology↗

bioRxiv2021

De novo disease-associated mutations in KIF1A dominant negatively inhibit axonal transport of synaptic vesicle precursors

KIF1A is a kinesin superfamily molecular motor that transports synaptic vesicle precursors in axons. Mutations in Kif1a lead to a group of neuronal diseases called KIF1A-associated neuronal disorder (KAND). KIF1A forms a homodimer and KAND mutations are mostly de novo and autosomal dominant; however, it is not known whether the function of wild-type KIF1A is inhibited by disease-associated KIF1A when they are dimerized. No reliable in vivo model systems to analyze the molecular and cellular biology of KAND caused by loss of function mutations have been developed; therefore, here, we established Caenorhabditis elegans models for KAND using CRISPR/cas9 technology and analyzed defects in axonal transport. In the C. elegans models, heterozygotes and homozygotes exhibited reduced axonal transport phenotypes. Suppressor screening using the disease model worm identified a mutation that recovers the motor activity of disease-associated human KIF1A. In addition, we developed in vitro assays to analyze the motility of single heterodimers composed of wild-type KIF1A and disease-associated KIF1A. Disease-associated KIF1A significantly inhibited the motility of wild-type KIF1A when heterodimers were formed. These data indicate the molecular mechanism underlying the dominant nature of de novo KAND mutations. Significance StatementKIF1A is a molecular motor that transports synaptic vesicle precursors in axons. Recent studies have identified many KIF1A mutations in congenital neuropathy patients; however, the molecular mechanism of pathogenesis remains largely elusive. This study established loss of function models for KIF1A-associated neuronal disorder (KAND) in Caenorhabditis elegans to analyze the molecular and cell biology of the disease in vivo. Genetic screening using the disease model could find a mutation that recovers the motor activity of disease-associated KIF1A. This study also established in vitro single-molecule assays to quantitatively analyze the effect of KAND mutations when mutant KIF1A forms heterodimers with wild-type KIF1A. Our findings provide a foundation for future genetic screening and for drug screening to search for KAND treatments.

cell biology↗

bioRxiv2021

Actin-related protein 5 functions as a novel modulator of MyoD and MyoG in skeletal muscle and in rhabdomyosarcoma

Myogenic regulatory factors (MRFs) are pivotal transcription factors in myogenic differentiation. MyoD commits cells to the skeletal muscle lineage by inducing myogenic genes through recruitment of chromatin remodelers to its target loci. This study showed that Actin-related protein 5 (Arp5) acts as an inhibitory regulator of MyoD and MyoG by binding to their cysteine-rich (CR) region, which overlaps with the region essential for their epigenetic functions. Arp5 expression was faint in skeletal muscle tissues. Excessive Arp5 in mouse hind limbs caused skeletal muscle fiber atrophy. Further, Arp5 overexpression in myoblasts inhibited myotube formation by diminishing myogenic gene expression, whereas Arp5 depletion augmented myogenic gene expression. Arp5 disturbed MyoD-mediated chromatin remodeling through competition with the three-amino-acid-loop-extension-class homeodomain transcription factors the Pbx1-Meis1 heterodimer for binding to the CR region. This antimyogenic function was independent of the INO80 chromatin remodeling complex, although Arp5 is an important component of that. In rhabdomyosarcoma (RMS) cells, Arp5 expression was significantly higher than in normal myoblasts and skeletal muscle tissue, probably contributing to MyoD and MyoG activity dysregulation. Arp5 depletion in RMS partially restored myogenic properties while inhibiting tumorigenic properties. Thus, Arp5 is a novel modulator of MRFs in skeletal muscle differentiation.

developmental biology↗

bioRxiv2020

Neutralizing antibody-dependent and -independent immune responses against SARS-CoV-2 in cynomolgus macaques

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infectious disease (COVID-19) has been threatening the world because of severe symptoms and relatively high mortality. To develop vaccines and antiviral drugs for COVID-19, an animal model of SARS-CoV-2 infection is required to evaluate the efficacy of prophylactics and therapeutics in vivo. Therefore, we examined the pathogenicity of SARS-CoV-2 in cynomolgus macaques until 28 days after virus inoculation in the present study. Cynomolgus macaques showed body temperature rises after infection and X-ray radiographic viral pneumonia was observed in one of three macaques. However, none of the macaques showed life-threatening clinical signs of disease corresponding that approximately 80% of human patients did not show a critical disease in COVID-19. A neutralizing antibody against SARS-CoV-2 and T-lymphocytes that produced interferon (IFN)-{gamma} and interleukin (IL)-2 specifically for SARS-CoV-2 N protein were detected on day 14 in the macaque that showed viral pneumonia. On the other hand, in the other macaques, in which a neutralizing antibody was not detected, T-lymphocytes that produced IFN-{gamma} specifically for SARS-CoV-2 N protein increased on day 7 to day 14 prior to an increase in the number of T-lymphocytes that produced IL-2. These results suggest that not only a neutralizing antibody but also cellular immunity augmented by IFN-{gamma} has a role in the elimination of SARS-CoV-2. Thus, because of the mild clinical signs of disease and low/no antibody responses against SARS-CoV-2 in two thirds of the macaques, cynomolgus macaques are appropriate to extrapolate human responses in vaccine and drug development. Author SummarySevere acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infectious disease (COVID-19) has been threatening the world. To develop vaccines and antiviral drugs for COVID-19, an animal model of SARS-CoV-2 infection is required to evaluate their efficacy in vivo. Therefore, we examined the pathogenicity of SARS-CoV-2 in a non-human primate model until 28 days after virus inoculation. Cynomolgus macaques showed a fever after infection and X-ray radiographic viral pneumonia was observed in one of three macaques. However, none of the macaques showed life-threatening symptoms. A neutralizing antibody against SARS-CoV-2 and T-lymphocytes that produced interferon (IFN)-{gamma} and interleukin (IL)-2 specifically for SARS-CoV-2 protein were detected on day 14 in the macaque that showed viral pneumonia. In the other macaques, in which a neutralizing antibody was not detected, T-lymphocytes that produced IFN-{gamma} specifically for SARS-CoV-2 N protein increased on day 7 to day 14. These results suggest that not only a neutralizing antibody but also cellular immunity augmented by IFN-{gamma} has a role in the elimination of SARS-CoV-2. Thus, because of the mild symptoms and low/no antibody responses against SARS-CoV-2 in two thirds of the macaques, cynomolgus macaques are appropriate to extrapolate human responses in vaccine and drug development.

microbiology↗