Comparative transcriptome analysis between rhesus macaques(Macaca mulatta) and crab-eating macaques(M. fascicularis)

Understanding gene expression variations between species is pivotal for deciphering the evolutionary diversity in phenotypes. Rhesus macaques(Macaca mulatta, MMU)and crab-eating macaques(M. fascicularis, MFA) serve as crucial nonhuman primate biomedical models with different phenotypes. To date, however, large-scale comparative transcriptome research between these two species has not yet been fully explored. Here, we conducted systematic comparisons utilizing newly sequenced RNA-seq data from84 samples(41 MFA samples and 43 MMU samples)encompassing 14 common tissues. Our findings revealed a small fraction of genes(3.7%) with differential expression between the two species, as well as 36.5% of genes with tissue-specific expression in both macaques. Comparison of gene expression between macaques and humans indicated that 22.6% of orthologous genes displayed differential expression in at least two tissues. Moreover,19.41% of genes that overlapped with macaque-specific structural variants showed differential expression between humans and macaques. Of these, the FAM220A gene exhibited elevated expression in humans compared to macaques due to lineage-specific duplication. In summary,this study presents a large-scale transcriptomic comparison between MMU and MFA and between macaques and humans. The discovery of gene expression variations not only enhances the biomedical utility of macaque models but also contributes to the wider field of primate genomics.

Social rank and cortisol among female rhesus macaques(Macaca mulatta)

In animal societies,some stressful events can lead to higher levels of physiological stress.Such stressors,like social rank,also predict an increased vulnerability to an array of diseases.However,the physiological relationship between social rank and stress varies between different species,as well as within groups of a single species.For example,dominant individuals are more socially stressed at times,while at other times it is the subordinate ones who experience this stress.Together,these variations make it difficult to assess disease vulnerability as connected to social interactions.In order to learn more about how physiological rank relationships vary between groups of a single species,cortisol measurements from hair samples were used to evaluate the effects of dominance rank on long-term stress levels in despotic and less stringent female rhesus macaque hierarchal groups.In despotic groups,cortisol levels were found not to be correlated with social rank,but a negative correlation was found between social rank and cortisol levels in less stringent hierarchies.Low ranking monkeys in less stringent groups secreted elevated levels of cortisol compared to higher ranking animals.These data suggest that variations in the strictness of the dominance hierarchy are determining factors in rank related stress physiology.The further consideration of nonhuman primate social system diversity and the linear degree of their hierarchies may allow for the development of valid rank-related stress models that will help increase our understanding and guide the development of new therapeutics for diseases related to human socioeconomic status.

Social rank and cortisol among female rhesus macaques (Macaca mulatta)

In animal societies, some stressful events can lead to higher levels of physiological stress. Such stressors, like social rank, also predict an increased vulnerability to an array of diseases. However, the physiological relationship between social rank and stress varies between different species, as well as within groups of a single species. For example, dominant individuals are more socially stressed at times, while at other times it is the subordinate ones who experience this stress. Together, these variations make it difficult to assess disease vulnerability as connected to social interactions. In order to learn more about how physiological rank relationships vary between groups of a single species, cortisol measurements from hair samples were used to evaluate the effects of dominance rank on long-term stress levels in despotic and less stringent female rhesus macaque hierarchal groups. In despotic groups, cortisol levels were found not to be correlated with social rank, but a negative correlation was found between social rank and cortisol levels in less stringent hierarchies. Low ranking monkeys in less stringent groups secreted elevated levels of cortisol compared to higher ranking animals. These data suggest that variations in the strictness of the dominance hierarchy are determining factors in rank related stress physiology. The further consideration of nonhuman primate social system diversity and the linear degree of their hierarchies may allow for the development of valid rank-related stress models that will help increase our understanding and guide the development of new therapeutics for diseases related to human socioeconomic status.

Disease Progression Patterns of SHIV-KB9 in Rhesus Macaques of Chinese Origin in Comparison with Indian Macaques

Objective To develop a model of SHIV-KB9/Chinese origin rhesus （Ch Rh） macaques for vaccine research and to compare the pathogenesis of SHIV-KB9 in Ch Rh macaques with that reported in Indian rhesus （Ind Rh） macaques. Methods Seven mamu-A＊01 negative Ch Rh macaques were inoculated intravenously with 1-10000 MID50 of SHIV-KB9. The monkeys were monitored for viral load, CD4, CDS, SHIV-specific antibody and virus genetic variation. The results were compared with those previously observed in Ind Rh macaques. Results As compared to that observed in Ind Rh macaques, SHIV-KB9 in Ch Rh macaques displayed three identical disease progression patterns. However, the primary pattern was not identical between the two subspecies. The level of plasma viremia differed in SHIV-KB9-infected Ch Rh macaques which exhibited different outcomes from those in Ind Rh macaques. Generally, the values of viral load and the maintenance of CD4^＋ T cells were associated with humoral responses. Otherwise, the viral genetic distances （divergence, diversity） were larger in animals （M419, M425） with their CD4^＋ T cells profoundly depleted. Conclusion The model of SHIV-KB9/Ch Rh macaques displays a relatively slow progression to AIDS compared with Ind Rh macaques, which may more accurately reflect the potential of candidate vaccines in humans.

Effect of sildenafil citrate on penile erection of rhesus macaques

Aim: To examine the effect of sildenafil citrate on penile erection of male rhesus macaque. Methods: Twenty Macaca mulatta were divided into the sildenafil treated and the control groups of 10 animals each. The penile size, the corpus cavernosal electromyogram (EMG) and the intra-corpus cavernosal pressure (ICP) were determined. Results: The diameter of penis and the ICP were significantly increased and the corpus cavernosal EMG significantly reduced in the sildenafil group. Conclusion: Sildenafil citrate increases the penile size and ICP and reduces the corpus cavernosal EMG in male rhesus macaque.

Parameter comparison of white matter diffusion tensor imaging （DTI） in rhesus macaques （Macaca mulatta）

In this study, we analyzed diffusion tensor imaging （DTI） results of brain white matter in rhesus macaques （Macaca mulatta） with four different parameter settings and found that the sequence A （b=1000 s/mm^2, spatial resolution=1.25 mm ×1.25 mm× 1.25 mm, numbers of direction=33, NSA=3） and B （b=800 s/mm^2, spatial resolution= 1.25 mm× 1.25 mm× 1.25 mm, numbers of direction=33, NSA=3） could accurately track coarse fibers. The fractional anisotropy （FA） derived from sequence C （b=1000s/mm^2, spatial resolution=0.55 mm×0.55 mm×2.5 mm, direction number=33, NSA=3） was too fuzzy to be used in tracking white matter fibers. By comparison, the high resolution and the FA with high contrast of gray matter and white matter derived from sequence D （b=800 s/mm^2, spatial resolution=1.0 mm×1.0 mm ×1.0 mm, numbers of direction=33, NSA=3） qualified in its application in tracking both thick and thin fibers, making it an optimal DTI setting for rhesus macaques.

Differential Transcriptomic Landscapes of SARS-CoV-2 Variants in Multiple Organs from Infected Rhesus Macaques

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)caused the persistent coronavirus disease 2019(COVID-19)pandemic,which has resulted in millions of deaths worldwide and brought an enormous public health and global economic burden.The recurring global wave of infections has been exacerbated by growing variants of SARS-CoV-2.In this study,the virological characteristics of the original SARS-CoV-2 strain and its variants of concern(VOCs;including Alpha,Beta,and Delta)in vitro,as well as differential transcriptomic landscapes in multiple organs(lung,right ventricle,blood,cerebral cortex,and cerebellum)from the infected rhesus macaques,were elucidated.The original strain of SARS-CoV-2 caused a stronger innate immune response in host cells,and its VOCs markedly increased the levels of subgenomic RNAs,such as N,Orf9b,Orf6,and Orf7ab,which are known as the innate immune antagonists and the inhibitors of antiviral factors.Intriguingly,the original SARS-CoV-2 strain and Alpha variant induced larger alteration of RNA abundance in tissues of rhesus monkeys than Beta and Delta variants did.Moreover,a hyperinflammatory state and active immune response were shown in the right ventricles of rhesus monkeys by the up-regulation of inflammation-and immune-related RNAs.Furthermore,peripheral blood may mediate signaling transmission among tissues to coordinate the molecular changes in the infected individuals.Collectively,these data provide insights into the pathogenesis of COVID-19 at the early stage of infection by the original SARS-CoV-2 strain and its VOCs.

Inhibitory effects of chloroquine on the activation of plasmacytoid dendritic cells in SIVmac239-infected Chinese rhesus macaques

It is currently widely accepted that immune activation in HIV-infected individuals leads to a severe loss of CD4＋ T cells and the progression to AIDS. However, the underlying mechanism of this immune activation remains unclear. Experimental data suggest that the activation of plasmacytoid dendritic cells （pDCs） by plasma viremia may play a critical role in HIV-induced immune activation. In this study, we found that the level of immune activation was higher in the late phase of SIVmac239 infection compared with chronic infection, which suggests that immune activation might be related to disease progression in SIVmac239-infected non-human primate models. Our work also showed that chloroquine could effectively inhibit the activation of pDCs in vitro and in vivo. However, chloroquine treatment of SIVmac239-infected macaques had no significant influence on the Cellular composition of peripheral blood in these animals.

The Influence of Age and Sex on the Cell Counts of Peripheral Blood Leukocyte Subpopulations in Chinese Rhesus Macaques

Non-human primates such as Chinese rhesus macaques are the favorable models for preclinical study of potential therapeutic drugs,vaccines and mechanisms of human diseases.Little is known about the normal levels of leukocyte subpopulations of Chinese rhesus macaques.To obtain these data,100 blood samples from Chinese rhesus macaques were collected.The normal range of major leukocyte subpopulations,such as T lymphocytes,B lymphocytes,monocytes,myeloid dendritic cells(mDCs)and plasmacytoid dendritic cells(pDCs),were quantitatively analyzed by flow cytometry through BD trucount tubes.The influence of age and sex on the cell counts of leukocyte subpopulations was analyzed.The counts of CD3^(+)T cells,CD3+CD4^(+)T cells,CD3+CD8^(+)T cells and B cells decreased with age,but those of monocytes,mDCs and pDCs had no significant correlation with age.Significant differences existed in the cell counts of most leukocyte subpopulations between the male and female groups except pDCs.Furthermore the values of the females were higher than those of the males.The study provided basic information about the leukocyte subpopulations of Chinese rhesus macaques,and it may be valuable for immunobiological study of Chinese rhesus macaques.

Differential transcriptomic landscapes of multiple organs from SARS-CoV-2 early infected rhesus macaques

SARS-CoV-2 infection causes complicated clinical manifestations with variable multi-organ injuries,how-ever,the underlying mechanism,in particular immune responses in different organs,remains elusive.In this study,comprehensive transcriptomic alterations of 14 tissues from rhesus macaque infected with SARS-CoV-2 were analyzed.Compared to normal controls,SARS-CoV-2 infection resulted in dysregulation of genes involving diverse functions in various examined tissues/organs,with drastic transcriptomic changes in cerebral cortex and right ventricle.Intriguingly,cerebral cortex exhibited a hyperinflammatory state evidenced by sig-nificant upregulation of inflammation response-related genes.Meanwhile,expressions of coagulation,angio-genesis and fibrosis factors were also up-regulated in cerebral cortex.Based on our findings,neuropilin 1(NRP1),a receptor of SARS-CoV-2,was significantly elevated in cerebral cortex post infection,accompanied by active immune response releasing inflammatory factors and signal transmission among tissues,which enhanced infection of the central nervous system(CNS)in a positive feedback way,leading to viral encephalitis.Overall,our study depicts a multi-tissue/organ tran-scriptomic landscapes of rhesus macaque with early infection of SARS-CoV-2,and provides important insights into the mechanistic basis for COVID-19-asso-ciated clinical complications.

Construction of Soluble Mamu-B~*1703,a Class I Major Histocompatibility Complex of Chinese Rhesus Macaques,Monomer and Tetramer Loaded with a Simian Immunodeficiency Virus Peptide

Chinese-descent rhesus macaques have become more prevalent for HIV infection and vaccine investigation than Indian-origin macaques. Most of the currently available data and reagents such as major histocompatibility complex （MHC） class I tetramers, however, were derived from Indian-origin macaques due to the dominant use of these animals in history. Although there are significant differences in the immunogenetic background between the two macaque populations, they share a few of common MHC class I alleles. We reported in this study the procedure for preparation of a soluble Mamu-B＊1703 （a MHC class I molecule of Chinese macaques） monomer and tetramer loaded with a dominant simian immunodeficiency virus （SIV） epitope IW9 （IRYPKTFGW） that was identified to be Mamu-B＊1701-restricted in Indian macaques. The DNA fragment encoding the Mamu-B＊1703 extracellular domain fused with a BirA substrate peptide （BSP） was amplified from a previously cloned cDNA and inserted into a prokaratic expression vector. In the presence of the antigenic peptide IW9 and light chain β2-microglobulin, the expressed heavy chain was refolded into a soluble monomer. After biotinylation, four monomers were polymerized as a tetramer by phycoerythrin-conjugated streptavidin. The tetramer, having been confirmed to have the right conformation, was a potential tool for investigation of antigen-specific CD8^＋ T-lymphocytes in SIV vaccine models of Chinese macaques. And our results also suggested that some antigenic peptides reported in Indian-origin macaques could be directly recruited as ligands for construction of Chinese macaque MHC tetramers.

Pathogenic analysis of coxsackievirus A10 in rhesus macaques

Coxsackievirus A10(CV-A10)is one of the etiological agents associated with hand,foot and mouth disease(HFMD)and also causes a variety of illnesses in humans,including pneumonia,and myocarditis.Different people,particularly young children,may have different immunological responses to infection.Current CV-A10 infection animal models provide only a rudimentary understanding of the pathogenesis and effects of this virus.The characteristics of CV-A10 infection,replication,and shedding in humans remain unknown.In this study,rhesus macaques were infected by CV-A10 via respiratory or digestive route to mimic the HFMD in humans.The clinical symptoms,viral shedding,inflammatory response and pathologic changes were investigated in acute infection(1–11 day post infection)and recovery period(12–180 day post infection).All infected rhesus macaques during acute infection showed obvious viremia and clinical symptoms which were comparable to those observed in humans.Substantial inflammatory pathological damages were observed in multi-organs,including the lung,heart,liver,and kidney.During the acute period,all rhesus macaques displayed clinical signs,viral shedding,normalization of serum cytokines,and increased serum neutralizing antibodies,whereas inflammatory factors caused some animals to develop severe hyperglycemia during the recovery period.In addition,there were no significant differences between respiratory and digestive tract infected animals.Overall,all data presented suggest that the rhesus macaques provide the first non-human primate animal model for investigating CV-A10 pathophysiology and assessing the development of potential human therapies.

Phenotype and Function of Monocyte-Derived Dendritic Cells from Chinese Rhesus Macaques

Dendritic cells （DCs） play a pivotal role in linking the innate immunity and acquired immunity in responses to pathogen. Non-human primates such as Chinese Rhesus Macaque （CRM） are the favorable models for preclinical study of potential therapeutic drugs, vaccines and mechanisms of human diseases. However, the phenotypical characterization of monocyte-derived dendritic cells （MDDCs） from CRM has not been elucidated. Monocytes from CRM were cultured with GM-CSF and IL-4 in RPMI-1640. Six days later, these cells were differentiated with typical dendritical morphology. CDllc and DC-SIGN were highly expressed. The immature MDDCs expressed the low levels of CD25, CD80, CD83, moderate CD40, CD86, and high MHC. After stimulation, the mature MDDCs increased expression of mature molecules CD25 and CD83, co-stimulatory molecules such as CD80, CD86 and CD40, and kept a high level of MHC. The capacity of endocytosis decreased with maturation. The mature MDDCs have strong ability of inducing allogeneic T cell proliferation and producing IL-12. In conclusion, we have characterized the phenotype and ultimate function of MDDCs from CRM for the first time.

Single-nucleus transcriptomic profiling of multiple organs in a rhesus macaque model of SARS-CoV-2 infection

Infection with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) causes diverse clinical manifestations and tissue injuries in multiple organs.However, cellular and molecular understanding of SARS-CoV-2 infection-associated pathology and immune defense features in different organs remains incomplete. Here, we profiled approximately 77 000single-nucleus transcriptomes of the lung, liver,kidney, and cerebral cortex in rhesus macaques(Macaca mulatta) infected with SARS-CoV-2 and healthy controls. Integrated analysis of the multiorgan dataset suggested that the liver harbored the strongest global transcriptional alterations. We observed prominent impairment in lung epithelial cells, especially in AT2 and ciliated cells, and evident signs of fibrosis in fibroblasts. These lung injury characteristics are similar to those reported in patients with coronavirus disease 2019(COVID-19).Furthermore, we found suppressed MHC class I/II molecular activity in the lung, inflammatory response in the liver, and activation of the kynurenine pathway,which induced the development of an immunosuppressive microenvironment. Analysis of the kidney dataset highlighted tropism of tubule cells to SARS-CoV-2, and we found membranous nephropathy(an autoimmune disease) caused by podocyte dysregulation. In addition, we identified the pathological states of astrocytes and oligodendrocytes in the cerebral cortex, providing molecular insights into COVID-19-related neurological implications. Overall, our multi-organ single-nucleus transcriptomic survey of SARS-CoV-2-infected rhesus macaques broadens our understanding of disease features and antiviral immune defects caused by SARS-CoV-2 infection,which may facilitate the development of therapeutic interventions for COVID-19.

Dysbiosis of gut microbiome affecting small intestine morphology and immune balance:a rhesus macaque model

There is a growing appreciation for the specific health benefits conferred by commensal microbiota on their hosts.Clinical microbiota analysis and animal studies in germ-free or antibiotic-treated mice have been crucial for improving our understanding of the role of the microbiome on the host mucosal surface;however,studies on the mechanisms involved in microbiome-host interactions remain limited to small animal models.Here,we demonstrated that rhesus monkeys under short-term broad-spectrum antibiotic treatment could be used as a model to study the gut mucosal host-microbiome niche and immune balance with steady health status.Results showed that the diversity and community structure of the gut commensal bacteria in rhesus monkeys were both disrupted after antibiotic treatment.Furthermore,the 16S rDNA amplicon sequencing results indicated that Escherichia-Shigella were predominant in stool samples 9 d of treatment,and the abundances of bacterial functional genes and predicted KEGG pathways were significantly changed.In addition to inducing aberrant morphology of small intestinal villi,the depletion of gut commensal bacteria led to increased proportions of CD3+T,CD4+T,and CD16+NK cells in peripheral blood mononuclear cells(PBMCs),but decreased numbers of Treg and CD20+B cells.The transcriptome of PBMCs from antibiotic-treated monkeys showed that the immune balance was affected by modulation of the expression of many functional genes,including IL-13,VCAM1,and LGR4.

How does the motor relearning program improve neurological function of brain ischemia monkeys?

The motor relearning program can significantly improve various functional disturbance induced by ischemic cerebrovascular diseases. However, its mechanism of action remains poorly understood. In injured brain tissues, glial fibrillary acidic protein and neurofilament protein changes can reflect the condition of injured neurons and astrocytes, while vascular endothelial growth factor and basic fibroblast growth factor changes can indicate angiogenesis. In the present study, we induced ischemic brain injury in the rhesus macaque by electrocoagulation of the M1 segment of the right middle cerebral artery. The motor relearning program was conducted for 60 days from the third day after model establishment. Immunohistochemistry and single-photon emission CT showed that the numbers of glial fibrillary acidic protein-, neurofilament protein-, vascular endothelial growth factor- and basic fibroblast growth factor-positive cells were significantly increased in the infarcted side compared with the contralateral hemisphere following the motor relearning program. Moreover, cerebral blood flow in the infarcted side was significantly improved. The clinical rating scale for stroke was used to assess neurological function changes in the rhesus macaque following the motor relearning program. Results showed that motor function was improved, and problems with consciousness, self-care ability and balance function were significantly ameliorated. These findings indicate that the motor relearning program significantly promoted neuronal regeneration, repair and angiogenesis in the surroundings of the infarcted hemisphere, and improve neurological function in the rhesus macaque following brain ischemia.

Age-related effects of estrogen on the expression of estrogen receptor (ER) α and β mRNA in the ovariectomized (OVX) monkey hypothalamus

In the present study, we reported distribution of ERα and ER β mRNAs in the hypothalamus of young and old ovariectomized （OVX） rhesus macaques. The ERα were detected in all six major vestiblular nuclei which included arcuate nucleus （ARC） , paraventricularis nucleus （PVN） , periventricular nucleus （PeriV） , supraoptic nucleus （SON）, medial prioptic nucleus （MPN） and lateral hypotbalamus area （LHA）. However, the ERβ mRNA can also detected in those nuclei excerpt SON, but the signals of ERβ mRNA were weaker than those of ERα mRNA. We observed that the degree of expression of ERs mRNA were different in most nucleus of old and young monkeys. The ERα mRNAs were highly expressed in ARC and SON in young monkeys compared with old monkeys. Moderate amount of ERα mRNAs hybridization signals and weak signals were observed in LHA, and MPN both in young and old monkeys. In contrast, only lower level of ERα hybridization signal were observed in PVN and PeriV in young monkeys, and the signals of ERα were very low in those nucleus of old monkeys. In general, the expression of ERβ mRNA were weaker than that of ERα mRNA in above nucleus excerpt LHA. The relatively higher density of ERβ hybridization signals have been observed in the LHA in young monkey compared with old monkeys. Low amount of. ERβ mRNA hybridization signals were observed in the ARC, PVN and MPN, and no age differences were seen in PVN and MPN of those monkeys. In PeriV, we observed some signals in young monkey and a few signals in old monkeys. It was different from the rodent in which we did not found ERβ hybridization signal in SON. This study showed that both of the two estrogen receptors not only had the same pattern of expression but also had many different patterns of expression. The different expression of ERα and ERβ mRNAs in the young and old monkey brain may imply diverse functions in different regions of the monkey brain.

Identification and analysis of intermediate-size noncoding RNAs in the rhesus macaque fetal brain

Although only about 2%of the human genome has proved to be protein-coding genes,recent advances in genome wide analysis have revealed that the majority of the genome is transcribed,mainly from noncoding segments that were once considered＂junk sequences＂or＂dark matters＂（Liu et al.,2011a;Zhang et al.,2014b）. In addition to the well-characterized housekeeping non- coding RNAs （ncRNAs） （tRNA, rRNA, small nuclear RNA and small nucleolar RNAs） and some small regulatory ncRNAs （microRNAs and small interfering RNAs）, the transcriptome of mammals could also pervasively have been transcribed long noncoding RNAs （lncRNAs, at least 200 nt） （Rinn and Chang, 2012; Xie et al., 2012）.

3D anatomy of autonomic innervations in immune organs of a non-human primate and the human

Direct neural inputs to immune organs have been observed for decades,with their functions in neuroimmune regulation being increasingly appreciated.However,the current knowledge of such neural structures,particularly those in primate immune organs,remains incomplete.In this study,we comprehensively assessed the 3D anatomy of autonomic(i.e.,sympathetic and parasympathetic)innervations in the immune organs of the rhesus macaque monkey and the human for the first time.Aided with the advanced technique of whole-tissue immunolabeling and lightsheet fluorescence imaging,we revealed the densely organized sympathetic architecture in the parenchyma of the adult monkey and human spleens.On the other hand,only sparse,if any,sympathetic inputs were observed inside the lymph nodes,Peyer's patches,or thymus.In contrast,there were minimal parasympathetic innervations in the parenchyma of these examined immune organs.Together,this work has documented the unique patterns of autonomic innervations in different immune organs of a non-human primate and the human,serving as an essential reference for future research on neuroimmune regulation in the field.

Recent advances in myeloid-derived suppressor cell biology

In recent years,studying the role of myeloid-derived suppressor cells(MDSCs)in many pathological inflammatory conditions has become a very active research area.Although the role of MDSCs in cancer is relatively well established,their role in non-cancerous pathological conditions remains in its infancy resulting in much confusion.Our objectives in this review are to address some recent advances in MDSC research in order to minimize such confusion and to provide an insight into their function in the context of other diseases.The following topics will be specifically focused upon:(1)definition and characterization of MDSCs;(2)whether all MDSC populations consist of immature cells;(3)technical issues in MDSC isolation,estimation and characterization;(4)the origin of MDSCs and their anatomical distribution in health and disease;(5)mediators of MDSC expansion and accumulation;(6)factors that determine the expansion of one MDSC population over the other;(7)the Yin and Yang roles of MDSCs.Moreover,the functions of MDSCs will be addressed throughout the text.