Generation of transgenic cynomolgus monkeys that express green fluorescent protein throughout the whole body

Generation of a familial hypercholesterolemia model in non-human primate

Familial hypercholesterolemia (FH) is an inherited autosomal dominant disorder that is associated with a high plasma level of low-density lipoprotein (LDL) cholesterol, leading to an increased risk of cardiovascular diseases. To develop basic and translational research on FH, we here generated an FH model in a non-human primate (cynomolgus monkeys) by deleting the LDL receptor (LDLR) gene using the genome editing technique. Six LDLR knockout (KO) monkeys were produced, all of which were confirmed to have mutations in the LDLR gene by sequence analysis. The levels of plasma cholesterol and triglyceride were quite high in the monkeys, and were similar to those in FH patients with homozygous mutations in the LDLR gene. In addition, periocular xanthoma was observed only 1 year after birth. Lipoprotein profile analysis showed that the plasma very low-density lipoprotein and LDL were elevated, while the plasma high density lipoprotein was decreased in LDLR KO monkeys. The LDLR KO monkeys were also strongly resistant to medications for hypercholesterolemia. Taken together, we successfully generated a non-human primate model of hypercholesterolemia in which the phenotype is similar to that of homozygous FH patients.

Gene editing monkeys: Retrospect and outlook

Animal models play a key role in life science research, especially in the study of human disease pathogenesis and drug screening. Because of the closer proximity to humans in terms of genetic evolution, physiology, immunology, biochemistry, and pathology, nonhuman primates (NHPs) have outstanding advantages in model construction for disease mechanism study and drug development. In terms of animal model construction, gene editing technology has been widely applied to this area in recent years. This review summarizes the current progress in the establishment of NHPs using gene editing technology, which mainly focuses on rhesus and cynomolgus monkeys. In addition, we discuss the limiting factors in the applications of genetically modified NHP models as well as the possible solutions and improvements. Furthermore, we highlight the prospects and challenges of the gene-edited NHP models.

In utero electroporation and cranial window implantation for in vivo wide-field two-photon calcium imaging using G-CaMP9a transgenic mice

We present a protocol to prepare mouse cranial window implantation for in vivo two-photon wide-field calcium imaging. This protocol uses G-CaMP9a transgenic mice, which express a genetically encoded calcium indicator with high signal-to-noise ratio. We describe in utero electroporation, followed by headplate fixation and cranial window implantation. This protocol can be used for measuring neural activity and is suitable for long-term imaging in large populations. Moreover, this protocol does not require preparation of Flp-expressing transgenic mice.

For complete details on the use and execution of this protocol, please refer to Sakamoto et al. (2022).

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Preparation of G-CaMP9a knock-in mice for in vivo calcium imaging

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In utero electroporation to introduce Flp recombinase in G-CaMP9a mice

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Implantation of cranial window for in vivo two-photon calcium imaging

Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Modeling genetic diseases in nonhuman primates through embryonic and germline modification: Considerations and challenges

Genetic modification of the embryo or germ line of nonhuman primates is envisioned as a method to develop improved models of human disease, yet the promise of such animal models remains unfulfilled. Here, we discuss current methods and their limitations for producing nonhuman primate genetic models that faithfully genocopy and phenocopy human disease. We reflect on how to ethically maximize the translational relevance of such models in the search for new therapeutic strategies to treat human disease.

Embryo-Engineered Nonhuman Primate Models: Progress and Gap to Translational Medicine

Animal models of human diseases are vital in better understanding the mechanism of pathogenesis and essential for evaluating and validating potential therapeutic interventions. As close relatives of humans, nonhuman primates (NHPs) play an increasingly indispensable role in advancing translational medicine research. In this review, we summarized the progress of NHP models generated by embryo engineering, analyzed their unique advantages in mimicking clinical patients, and discussed the remaining gap between basic research of NHP models to translational medicine.

Screening for gene doping transgenes in horses via the use of massively parallel sequencing

Throughout the history of horse racing, doping techniques to suppress or enhance performance have expanded to match the technology available. The next frontier in doping, both in the equine and human sports areas, is predicted to be genetic manipulation; either by prohibited use of genome editing, or gene therapy via transgenes. By using massively-parallel sequencing via a two-step PCR method we can screen for multiple doping targets at once in pooled primer sets. This method has the advantages of high scalability through combinational indexing, and the use of reference standards with altered sequences as controls. Custom software produces transgene-specific amplicons from any Ensembl-annotated genome to facilitate rapid assay design. Additional scripts batch-process FASTQ data from experiments, automatically quality-filtering sequences and assigning hits based on discriminatory motifs. We report here our experiences in establishing the workflow with an initial 31 transgene and vector feature targets. To evaluate the sensitivity of parallel sequencing in a real-world setting, we performed an intramuscular (IM) administration of a control rAAV vector into two horses and compared the detection sensitivity between parallel sequencing and real-time qPCR. Vector was detected by all assays on both methods up to 79 h post-administration, becoming sporadic after 96 h.

Generation of Transgenic Cynomolgus Monkeys Overexpressing the Gene for Amyloid-β Precursor Protein

Alzheimer’s disease (AD) is the most common cause of dementia and understanding its pathogenesis should lead to improved therapeutic and diagnostic methods. Although several groups have developed transgenic mouse models overexpressing the human amyloid-β precursor protein (APP) gene with AD mutations, with and without presenilin mutations, as well as APP gene knock-in mouse models, these animals display amyloid pathology but do not show neurofibrillary tangles or neuronal loss. This presumably is due to differences between the etiology of the aged-related human disease and the mouse models. Here we report the generation of two transgenic cynomolgus monkeys overexpressing the human gene for APP with Swedish, Artic, and Iberian mutations, and demonstrated expression of gene tagged green fluorescent protein marker in the placenta, amnion, hair follicles, and peripheral blood. We believe that these nonhuman primate models will be very useful to study the pathogenesis of dementia and AD. However, generated Tg monkeys still have some limitations. We employed the CAG promoter, which will promote gene expression in a non-tissue specific manner. Moreover, we used transgenic models but not knock-in models. Thus, the inserted transgene destroys endogenous gene(s) and may affect the phenotype(s). Nevertheless, it will be of great interest to determine whether these Tg monkeys will develop tauopathy and neurodegeneration similar to human AD.

Non-human primates as a model for human development

Human development has been studied for over a century, but the molecular mechanisms underlying human embryogenesis remain largely unknown due to technical difficulties and ethical issues. Accordingly, mice have been used as a model for mammalian development and studied extensively to infer human biology based on the conservation of fundamental processes between the two species. As research has progressed, however, species-specific differences in characteristics between rodents and primates have become apparent. Non-human primates (NHPs) have also been used for biomedical research, and are now attracting attention as a model for human development. Here, we summarize primate species from the evolutionary and genomic points of view. Then we review the current issues and progress in gene modification technology for NHPs. Finally, we discuss recent studies on the early embryogenesis of primates and future perspectives.

Assisted Reproductive Techniques and Genetic Manipulation in the Common Marmoset

Genetic modification of nonhuman primate (NHP) zygotes is a useful method for the development of NHP models of human diseases. This review summarizes the recent advances in the development of assisted reproductive and genetic manipulation techniques in NHP, providing the basis for the generation of genetically modified NHP disease models. In this study, we review assisted reproductive techniques, including ovarian stimulation, in vitro maturation of oocytes, in vitro fertilization, embryo culture, embryo transfer, and intracytoplasmic sperm injection protocols in marmosets. Furthermore, we review genetic manipulation techniques, including transgenic strategies, target gene knock-out and knock-in using gene editing protocols, and newly developed gene-editing approaches that may potentially impact the production of genetically manipulated NHP models. We further discuss the progress of assisted reproductive and genetic manipulation techniques in NHP; future prospects on genetically modified NHP models for biomedical research are also highlighted.

Generation and Breeding of EGFP-Transgenic Marmoset Monkeys: Cell Chimerism and Implications for Disease Modeling

Genetic modification of non-human primates (NHP) paves the way for realistic disease models. The common marmoset is a NHP species increasingly used in biomedical research. Despite the invention of RNA-guided nucleases, one strategy for protein overexpression in NHP is still lentiviral transduction. We generated three male and one female enhanced green fluorescent protein (EGFP)-transgenic founder marmosets via lentiviral transduction of natural preimplantation embryos. All founders accomplished germline transmission of the transgene by natural mating, yielding 20 transgenic offspring together (in total, 45 pups; 44% transgenic). This demonstrates that the transgenic gametes are capable of natural fertilization even when in competition with wildtype gametes. Importantly, 90% of the transgenic offspring showed transgene silencing, which is in sharp contrast to rodents, where the identical transgene facilitated robust EGFP expression. Furthermore, we consistently discovered somatic, but so far, no germ cell chimerism in mixed wildtype/transgenic litters. Somatic cell chimerism resulted in false-positive genotyping of the respective wildtype littermates. For the discrimination of transgenic from transgene-chimeric animals by polymerase chain reaction on skin samples, a chimeric cell depletion protocol was established. In summary, it is possible to establish a cohort of genetically modified marmosets by natural mating, but specific requirements including careful promoter selection are essential.

Comprehensive evaluation of ubiquitous promoters suitable for the generation of transgenic cynomolgus monkeys†

Nonhuman primates (NHPs) are considered to be the most valuable models for human transgenic (Tg) research into disease because human pathology is more closely recapitulated in NHPs than rodents. Previous studies have reported the generation of Tg NHPs that ubiquitously overexpress a transgene using various promoters, but it is not yet clear which promoter is most suitable for the generation of NHPs overexpressing a transgene ubiquitously and persistently in various tissues. To clarify this issue, we evaluated four putative ubiquitous promoters, cytomegalovirus (CMV) immediate-early enhancer and chicken beta-actin (CAG), elongation factor 1α (EF1α), ubiquitin C (UbC), and CMV, using an in vitro differentiation system of cynomolgus monkey embryonic stem cells (ESCs). While the EF1α promoter drove Tg expression more strongly than the other promoters in undifferentiated pluripotent ESCs, the CAG promoter was more effective in differentiated cells such as embryoid bodies and ESC-derived neurons. When the CAG and EF1α promoters were used to generate green fluorescent protein (GFP)-expressing Tg monkeys, the CAG promoter drove GFP expression in skin and hematopoietic tissues more strongly than in ΕF1α-GFP Tg monkeys. Notably, the EF1α promoter underwent more silencing in both ESCs and Tg monkeys. Thus, the CAG promoter appears to be the most suitable for ubiquitous and stable expression of transgenes in the differentiated tissues of Tg cynomolgus monkeys and appropriate for the establishment of human disease models.

Altered Response to Total Body Irradiation of C57BL/6-Tg (CAG-EGFP) Mice

Application of green fluorescent protein (GFP) in a variety of biosystems as a unique bioindicator or biomarker has revolutionized biological research and made groundbreaking achievements, while increasing evidence has shown alterations in biological properties and physiological functions of the cells and animals overexpressing transgenic GFP. In this work, response to total body irradiation (TBI) was comparatively studied in GFP transgenic C57BL/6-Tg (CAG-EGFP) mice and C57BL/6 N wild type mice. It was demonstrated that GFP transgenic mice were more sensitive to radiation-induced bone marrow death, and no adaptive response could be induced. In the nucleated bone marrow cells of GFP transgenic mice exposed to a middle dose, there was a significant increase in both the percentage of cells expressing pro-apoptotic gene Bax and apoptotic cell death. While in wild type cells, lower expression of pro-apoptotic gene Bax and higher expression of anti-apoptotic gene Bcl-2, and significant lower induction of apoptosis were observed compared to GFP transgenic cells. Results suggest that presence of GFP could alter response to TBI at whole body, cellular and molecular levels in mice. These findings indicate that there could be a major influence on the interpretation of the results obtained in GFP transgenic mice.

Monkeys mutant for PKD1 recapitulate human autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) caused by PKD1 mutations is one of the most common hereditary disorders. However, the key pathological processes underlying cyst development and exacerbation in pre-symptomatic stages remain unknown, because rodent models do not recapitulate critical disease phenotypes, including disease onset in heterozygotes. Here, using CRISPR/Cas9, we generate ADPKD models with PKD1 mutations in cynomolgus monkeys. As in humans and mice, near-complete PKD1 depletion induces severe cyst formation mainly in collecting ducts. Importantly, unlike in mice, PKD1 heterozygote monkeys exhibit cyst formation perinatally in distal tubules, possibly reflecting the initial pathology in humans. Many monkeys in these models survive after cyst formation, and cysts progress with age. Furthermore, we succeed in generating selective heterozygous mutations using allele-specific targeting. We propose that our models elucidate the onset and progression of ADPKD, which will serve as a critical basis for establishing new therapeutic strategies, including drug treatments.

Induction of the germ cell fate from pluripotent stem cells in cynomolgus monkeys†

In vitro reconstitution of germ-cell development from pluripotent stem cells (PSCs) has created key opportunities to explore the fundamental mechanisms underlying germ-cell development, particularly in mice and humans. Importantly, such investigations have clarified critical species differences in the mechanisms regulating mouse and human germ-cell development, highlighting the necessity of establishing an in vitro germ-cell development system in other mammals, such as non-human primates. Here, we show that multiple lines of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) in cynomolgus monkeys (Macaca fascicularis; cy) can be maintained stably in an undifferentiated state under a defined condition with an inhibitor for WNT signaling, and such PSCs are induced efficiently into primordial germ cell-like cells (PGCLCs) bearing a transcriptome similar to early cyPGCs. Interestingly, the induction kinetics of cyPGCLCs from cyPSCs is faster than that of human (h) PGCLCs from hPSCs, and while the transcriptome dynamics during cyPGCLC induction is relatively similar to that during hPGCLC induction, it is substantially divergent from that during mouse (m) PGCLC induction. Our findings delineate common as well as species-specific traits for PGC specification, creating a foundation for parallel investigations into the mechanism for germ-cell development in mice, monkeys, and humans.

Aging research using the common marmoset: Focus on aging interventions

Traditional animal models have been used to make seminal discoveries in biomedical research including a better understanding of the biology of the aging process. However, translation of these findings from laboratory to clinical populations has likely been hindered due to fundamental biological and physiological differences between common laboratory animals and humans. Non-human primates (NHP) may serve as an effective bridge towards translation, and short-lived NHP like the common marmoset offer many advantages as models for aging research. Here, we address these advantages and discuss what is currently understood about the changes in physiology and pathology that occur with age in the marmoset. In addition, we discuss how aging research might best utilize this model resource, and outline an ongoing study to address whether pharmaceutical intervention can slow aging in the marmoset. With this manuscript, we clarify how common marmosets might assist researchers in geroscience as a potential model for pre-clinical translation.

Highly efficient induction of primate iPS cells by combining RNA transfection and chemical compounds

Induced pluripotent stem (iPS) cells hold great promise for regenerative medicine and the treatment of various diseases. Before proceeding to clinical trials, it is important to test the efficacy and safety of iPS cell‐based treatments using experimental animals. The common marmoset is a new world monkey widely used in biomedical studies. However, efficient methods that could generate iPS cells from a variety of cells have not been established. Here, we report that marmoset cells are efficiently reprogrammed into iPS cells by combining RNA transfection and chemical compounds. Using this novel combination, we generate transgene integration‐free marmoset iPS cells from a variety of cells that are difficult to reprogram using conventional RNA transfection method. Furthermore, we show this is similarly effective for human and cynomolgus monkey iPS cell generation. Thus, the addition of chemical compounds during RNA transfection greatly facilitates reprogramming and efficient generation of completely integration‐free safe iPS cells in primates, particularly from difficult‐to‐reprogram cells.

Poor second ovarian stimulation in cynomolgus monkeys (Macaca fascicularis) is associated with the production of antibodies against human follicle-stimulating hormone

Cynomolgus monkeys (Macaca fascicularis) are a valuable model organism for human disease modeling because human physiology and pathology are closer to those of cynomolgus monkeys than rodents. It has been widely reported that mature oocytes can be recovered from cynomolgus monkeys through ovarian stimulation by human follicle-stimulating hormone (hFSH). However, it is unknown whether mature oocytes can be effectively obtained through a second ovarian stimulation by hFSH. Here, we report that some ovaries (eight ovaries from 14 female monkeys) were stimulated effectively by hFSH even after the first ovum pick up, whereas the others were stimulated poorly by hFSH. Furthermore, we found antibodies against hFSH only in the serum of female monkeys with poorly stimulated ovaries. Collectively, these data suggest that anti-hFSH antibodies in serum may cause a poor ovarian response to hFSH stimulation. Finally, detection of such antibodies as well as observation of the ovary over the course of hFSH administration might be useful to predict favorable second ovarian stimulation by hFSH.

Local transgene expression and whole-body transgenesis to model brain diseases in nonhuman primate

Animal model is an essential tool in the life sciences research, notably in understanding the pathogenesis of the diseases and for further therapeutic intervention success. Rodents have been the most frequently used animals to model human disease since the establishment of gene manipulation technique. However, they remain inadequate to fully mimic the pathophysiology of human brain disease, partially due to huge differences between rodents and humans in terms of anatomy, brain function, and social behaviors. Nonhuman primates are more suitable in translational perspective. Thus, genetically modified animals have been generated to investigate neurologic and psychiatric disorders. The classical transgenesis technique is not efficient in that model; so, viral vector-mediated transgene delivery and the new genome-editing technologies have been promoted. In this review, we summarize some of the technical progress in the generation of an ad hoc animal model of brain diseases by gene delivery and real transgenic nonhuman primate.

Large animals in neurointerventional research: A systematic review on models, techniques and their application in endovascular procedures for stroke, aneurysms and vascular malformations

Neuroendovascular procedures have led to breakthroughs in the treatment of ischemic stroke, intracranial aneurysms, and intracranial arteriovenous malformations. Due to these substantial successes, there is continuous development of novel and refined therapeutic approaches. Large animal models feature various conceptual advantages in translational research, which makes them appealing for the development of novel endovascular treatments. However, the availability and role of large animal models have not been systematically described so far. Based on comprehensive research in two databases, this systematic review describes current large animal models in neuroendovascular research including their primary use. It may therefore serve as a compact compendium for researchers entering the field or looking for opportunities to refine study concepts. It also describes particular applications for ischemic stroke and aneurysm therapy, as well as for the treatment of arteriovenous malformations. It focuses on most promising study designs and readout parameters, as well as on important pitfalls in endovascular translational research including ways to circumvent them.

Hyperandrogenic origins of polycystic ovary syndrome - implications for pathophysiology and therapy

INTRODUCTION

Polycystic ovary syndrome (PCOS) diagnosis comprises combinations of female hyperandrogenism, menstrual irregularity and polycystic ovaries. While it is a familial and highly prevalent endocrine disorder, progress towards a cure is hindered by absence of a definitive pathogenic mechanism and lack of an animal model of naturally occurring PCOS.

AREAS COVERED

These include an overview of PCOS and its potential etiology, and an examination of insights gained into its pathogenic origins. Animal models derived from experimentally-induced hyperandrogenism during gestation, or from naturally-occurring PCOS-like traits, most reliably demonstrate reproductive, neuroendocrine and metabolic pathogenesis.

EXPERT OPINION

Genetic studies, while identifying at least 17 PCOS risk genes, account for <10% of women with PCOS. A number of PCOS risk genes involve regulation of gonadotropin secretion or action, suggesting a reproductive neuroendocrine basis for PCOS pathogenesis. Consistent with this notion, a number of animal models employing fetal androgen excess demonstrate epigenetic induction of PCOS-like traits, including reproductive neuroendocrine and metabolic dysfunction. Monkey models are most comprehensive, while mouse models provide molecular insight, including identifying the androgen receptor, particularly in neurons, as mediating androgen-induced PCOS-like programming. Naturally-occurring female hyperandrogenism is also demonstrated in monkeys. Animal models are poised to delineate molecular gateways to PCOS pathogenesis.

Generation of genetically engineered non-human primate models of brain function and neurological disorders

Research with non-human primates (NHP) has been essential and effective in increasing our ability to find cures for a large number of diseases that cause human suffering and death. Extending the availability and use of genetic engineering techniques to NHP will allow the creation and study of NHP models of human disease, as well as broaden our understanding of neural circuits in the primate brain. With the recent development of efficient genetic engineering techniques that can be used for NHP, there's increased hope that NHP will significantly accelerate our understanding of the etiology of human neurological and neuropsychiatric disorders. In this article, we review the present state of genetic engineering tools used in NHP, from the early efforts to induce exogeneous gene expression in macaques and marmosets, to the latest results in producing germline transmission of different transgenes and the establishment of knockout lines of specific genes. We conclude with future perspectives on the further development and employment of these tools to generate genetically engineered NHP.

MHC-identical and transgenic cynomolgus macaques for preclinical studies

Cynomolgus macaques are useful experimental animals that are physiologically and genetically close to humans. We have developed two kinds of experimental usage of cynomolgus macaque: transplantation and disease models. First, we identified certain major histocompatibility complex (MHC) haplotypes including homozygotes and heterozygotes in cynomolgus macaques native to the Philippines, because they have less polymorphism in the MHC than that in other origins such as Vietnam and Indonesia. As a preclinical model of the induced pluripotent stem cell (iPSC) stock project, we established iPSCs from various types of MHC homozygous macaques, which were transplanted into compatible MHC heterozygous macaques, the iPSC stock project was experimentally shown to be effective. Second, to obtain disease models of cynomolgus macaques for studies on regenerative medicine including cell therapies, we established two kinds of genetic technology to modify cynomolgus macaques: transgenic technology and gene editing technology using CRISPR-Cas9. We will establish disease models, such as Alzheimer's disease and progeria (Werner syndrome). In future, we will distribute the MHC-identical cynomolgus monkeys and genetically modified macaques to researchers, especially those engaging in regenerative medicine.

The oxytocin system of mice and men-Similarities and discrepancies of oxytocinergic modulation in rodents and primates

Nonapeptides and their respective receptors have been conserved throughout evolution and display astonishing similarities among the animal kingdom. They can be found in worms, birds, fish, amphibians, reptiles and mammals, including rodents, non-human primates and humans. In particular, the neuropeptide oxytocin (OT) has attracted the attention of scientists due to its profound effects on social behavior. However, although both the neuropeptide and its receptor are identical in rodents and primates, the effects of OT vary greatly in the two species. Here, we provide a brief overview about OT's role in the evolution of mammals and provide reasons for the manifold effects of OT within the brain with a particular focus on the discrepancy of OT's effects in rodents and primates. In addition, we suggest new approaches towards improvement of translatability of scientific studies and highlight the most recent advances in animal models for autism spectrum disorder, a disease, in which the normal function of the OT system seems to be impaired.

Assisted reproductive technologies in the common marmoset: an integral species for developing nonhuman primate models of human diseases

Generation of nonhuman primate models of human disease conditions will foster the development of novel therapeutic strategies. Callithrix jacchus, or the common marmoset, is a New World, nonhuman primate species that exhibits great reproductive fitness in captivity with an ovarian cycle that can be easily managed with pharmacological agents. This characteristic, among others, provides an opportunity to employ assisted reproductive technologies to generate embryos that can be genetically manipulated to create a variety of nonhuman primate models for human disease. Here, we review methods to synchronize the marmoset ovarian cycle and stimulate oocyte donors, and compare various protocols for in vitro production of embryos. In light of advances in genomic editing, recent approaches used to generate transgenic or genetically edited embryos in the marmoset and also future perspective are reviewed.

Genetic engineering in nonhuman primates for human disease modeling

Nonhuman primate (NHP) experimental models have contributed greatly to human health research by assessing the safety and efficacy of newly developed drugs, due to their physiological and anatomical similarities to humans. To generate NHP disease models, drug-inducible methods, and surgical treatment methods have been employed. Recent developments in genetic and developmental engineering in NHPs offer new options for producing genetically modified disease models. Moreover, in recent years, genome-editing technology has emerged to further promote this trend and the generation of disease model NHPs has entered a new era. In this review, we summarize the generation of conventional disease model NHPs and discuss new solutions to the problem of mosaicism in genome-editing technology.

Single-cell transcriptome of early embryos and cultured embryonic stem cells of cynomolgus monkeys

In mammals, the development of pluripotency and specification of primordial germ cells (PGCs) have been studied predominantly using mice as a model organism. However, divergences among mammalian species for such processes have begun to be recognized. Between humans and mice, pre-implantation development appears relatively similar, but the manner and morphology of post-implantation development are significantly different. Nevertheless, the embryogenesis just after implantation in primates, including the specification of PGCs, has been unexplored due to the difficulties in analyzing the embryos at relevant developmental stages. Here, we present a comprehensive single-cell transcriptome dataset of pre- and early post-implantation embryo cells, PGCs and embryonic stem cells (ESCs) of cynomolgus monkeys as a model of higher primates. The identities of each transcriptome were also validated rigorously by other way such as immunofluorescent analysis. The information reported here will serve as a foundation for our understanding of a wide range of processes in the developmental biology of primates, including humans.

Non-human primate models of PD to test novel therapies

Non-human primate (NHP) models of Parkinson disease show many similarities with the human disease. They are very useful to test novel pharmacotherapies as reviewed here. The various NHP models of this disease are described with their characteristics including the macaque, the marmoset, and the squirrel monkey models. Lesion-induced and genetic models are described. There is no drug to slow, delay, stop, or cure Parkinson disease; available treatments are symptomatic. The dopamine precursor, L-3,4-dihydroxyphenylalanine (L-Dopa) still remains the gold standard symptomatic treatment of Parkinson. However, involuntary movements termed L-Dopa-induced dyskinesias appear in most patients after chronic treatment and may become disabling. Dyskinesias are very difficult to manage and there is only amantadine approved providing only a modest benefit. In this respect, NHP models have been useful to seek new drug targets, since they reproduce motor complications observed in parkinsonian patients. Therapies to treat motor symptoms in NHP models are reviewed with a discussion of their translational value to humans. Disease-modifying treatments tested in NHP are reviewed as well as surgical treatments. Many biochemical changes in the brain of post-mortem Parkinson disease patients with dyskinesias are reviewed and compare well with those observed in NHP models. Non-motor symptoms can be categorized into psychiatric, autonomic, and sensory symptoms. These symptoms are present in most parkinsonian patients and are already installed many years before the pre-motor phase of the disease. The translational usefulness of NHP models of Parkinson is discussed for non-motor symptoms.

miR-127 enhances myogenic cell differentiation by targeting S1PR3

MicroRNAs (miRNAs) have recently been implicated in muscle stem cell function. miR-127 is known to be predominantly expressed in skeletal muscle, but its roles in myogenic differentiation and muscle regeneration are unknown. Here, we show that miR-127 is upregulated during C2C12 and satellite cell (SC) differentiation and, by establishing C2C12 cells stably expressing miR-127, demonstrate that overexpression of miR-127 in C2C12 cells enhances myogenic cell differentiation. To investigate the function of miR-127 during muscle development and regeneration in vivo, we generated miR-127 transgenic mice. These mice exhibited remarkably accelerated muscle regeneration compared with wild-type mice by promoting SC differentiation. Mechanistically, we demonstrated that the gene encoding sphingosine-1-phosphate receptor 3 (S1PR3), a G-protein-coupled receptor for sphingosine-1-phosphate, is a target of miR-127 required for its function in promoting myogenic cell differentiation. Importantly, overexpression of miR-127 in muscular dystrophy model mdx mice considerably ameliorated the disease phenotype. Thus, our findings suggest that miR-127 may serve as a potential therapeutic target for the treatment of skeletal muscle disease in humans.