Adult Rhesus Macaques Research Articles

Genetic polymorphisms in the serotonin, dopamine and opioid pathways influence social attention in rhesus macaques (Macaca mulatta).

Behaviour has a significant heritable component; however, unpicking the variants of interest in the neural circuits and molecular pathways that underpin these has proven difficult. Here, we present a comprehensive analysis of the relationship between known and new candidate genes from identified pathways and key behaviours for survival in 109 adult rhesus macaques (Macaca mulatta). Eight genes involved in emotion were analysed for variation at a total of nine loci. Genetic data were then correlated with cognitive and observational measures of behaviour associated with wellbeing and survival using MCMC-based Bayesian GLMM in R, to account for relatedness within the macaque population. For four loci the variants genotyped were length polymorphisms (SLC6A4 5-hydroxytryptamine transporter length-polymorphic repeat (5-HTTLPR), SLC6A4 STin polymorphism, Tryptophan 5-hydroxylase 2 (TPH2) and Monoamine oxidase A (MAOA)) whilst for the other five (5-hydroxytryptamine receptor 2A (HTR2A), Dopamine Receptor D4 (DRD4), Oxytocin receptor (OXTR), Arginine vasopressin receptor 1A (AVPR1a), Opioid receptor mu(μ) 1 (OPRM1)) SNPs were analysed. STin genotype, DRD4 haplotype and OXTR haplotype were significantly associated with the cognitive and observational measures of behaviour associated with wellbeing and survival. Genotype for 5-HTTLPR, STin and AVPR1a, and haplotype for HTR2A, DRD4 and OXTR were significantly associated with the duration of behaviours including fear and anxiety. Understanding the biological underpinnings of individual variation in negative emotion (e.g., fear and anxiety), together with their impact on social behaviour (e.g., social attention including vigilance for threat) has application for managing primate populations in the wild and captivity, as well as potential translational application for understanding of the genetic basis of emotions in humans.

Error detection and correction in intracortical brain–machine interfaces controlling two finger groups

Objective. While brain–machine interfaces (BMIs) are promising technologies that could provide direct pathways for controlling the external world and thus regaining motor capabilities, their effectiveness is hampered by decoding errors. Previous research has demonstrated the detection and correction of BMI outcome errors, which occur at the end of trials. Here we focus on continuous detection and correction of BMI execution errors, which occur during real-time movements. Approach. Two adult male rhesus macaques were implanted with Utah arrays in the motor cortex. The monkeys performed single or two-finger group BMI tasks where a Kalman filter decoded binned spiking-band power into intended finger kinematics. Neural activity was analyzed to determine how it depends not only on the kinematics of the fingers, but also on the distance of each finger-group to its target. We developed a method to detect erroneous movements, i.e. consistent movements away from the target, from the same neural activity used by the Kalman filter. Detected errors were corrected by a simple stopping strategy, and the effect on performance was evaluated. Main results. First we show that including distance to target explains significantly more variance of the recorded neural activity. Then, for the first time, we demonstrate that neural activity in motor cortex can be used to detect execution errors during BMI controlled movements. Keeping false positive rate below , it was possible to achieve mean true positive rate of online. Despite requiring 200 ms to detect and react to suspected errors, we were able to achieve a significant improvement in task performance via reduced orbiting time of one finger group. Significance. Neural activity recorded in motor cortex for BMI control can be used to detect and correct BMI errors and thus to improve performance. Further improvements may be obtained by enhancing classification and correction strategies.

Adeno-associated viral vectors for functional intravenous gene transfer throughout the non-human primate brain

Crossing the blood–brain barrier in primates is a major obstacle for gene delivery to the brain. Adeno-associated viruses (AAVs) promise robust, non-invasive gene delivery from the bloodstream to the brain. However, unlike in rodents, few neurotropic AAVs efficiently cross the blood–brain barrier in non-human primates. Here we report on AAV.CAP-Mac, an engineered variant identified by screening in adult marmosets and newborn macaques, which has improved delivery efficiency in the brains of multiple non-human primate species: marmoset, rhesus macaque and green monkey. CAP-Mac is neuron biased in infant Old World primates, exhibits broad tropism in adult rhesus macaques and is vasculature biased in adult marmosets. We demonstrate applications of a single, intravenous dose of CAP-Mac to deliver functional GCaMP for ex vivo calcium imaging across multiple brain areas, or a cocktail of fluorescent reporters for Brainbow-like labelling throughout the macaque brain, circumventing the need for germline manipulations in Old World primates. As such, CAP-Mac is shown to have potential for non-invasive systemic gene transfer in the brains of non-human primates.

Transcriptomic changes in the hypothalamus of rhesus monkeys with bone marrow mesenchymal stem cells treatment

Background: It is acknowledged that the hypothalamus plays an important role in the regulation of aging, and bone marrow mesenchymal stem cells (BMSCs) possess an anti-aging effect, this study was therefore designed to investigate transcriptomic changes in the hypothalamus of aged rhesus monkeys with BMSCs-treatment to explore the underlying molecular mechanism for the anti-aging effect of BMSCs. Methods: Transcriptome profiling sequencing was conducted on the juvenile rhesus macaques (YN), adult rhesus macaques (QN), aged rhesus macaques (LN) and BMSCs-treated aged rhesus macaques (ZL). Then, differentially expressed genes (DEG) analysis was performed between YN and QN, QN and LN, LN and ZL, respectively. After the intersection of DEGs from these three pairs of comparisons, screened intersecting genes were subject to GO (Gene Ontology) enrichment analysis, KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis and PPI (protein-protein interaction) analysis to explore their interactions and underlying mechanism of BMSCs for retarding aging. Lastly, according to the results of PPI and the most enriched GO term, we further integrated and screened genes, which were regarded as aging-related genes in the hypothalamus. Results: According to obtained transcriptome profiling data, 671 differentially expressed genes were screened between QN and YN, 1315 genes between LN and QN, and 1345 genes between ZL and LN. After intersecting, 53 genes were screened out. GO analysis showed that most genes were mainly enriched in intercellular adhesion, sphingosinol biosynthesis, ceramide biosynthesis in BP, while in the cell membrane group and Golgi membrane in CC. PPI suggested that SPTLC2, ASAH2, FA2H and other genes had higher core degrees, indicating these hub genes may be involved in the process of aging by lipid metabolism. After the final screening, a total of 28 genes with significant differences were screened out, among which GPR68, LOC706331, STRA6 and PDE7B were up-regulated in QN and ZL compared with YN and LN respectively, while down-regulated in LN compared with QN. The other 24 genes were down-regulated in QN and ZL compared with YN and LN respectively, while up-regulated in LN compared with QN. Conclusion: A total of 28 genes were recognized as aging-related genes in the hypothalamus, and BMSCs treatment for retarding aging may be involved in these gene targets.

Expression of tau and phosphorylated tau in the brain of normal and hemiparkinsonian rhesus macaques.

Tau is a neuronal protein involved in microtubule stabilization and intracellular vesicle transport in axons. In neurodegenerative disorders termed "tauopathies," like Alzheimer's and Parkinson's disease, tau becomes hyperphosphorylated and forms intracellular inclusions. Rhesus macaques are widely used for studying ageing processes and modeling neurodegenerative disorders, yet little is known about endogenous tau expression in their brains. In this study, immunohistochemical methods were used to map and characterize total tau, 3R- and 4R-tau isoforms, and phosphorylated tau (pThr231-tau and pSer202/Thr205-tau/AT8) expression bilaterally in 16 brain regions of normal and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced hemiparkinsonian adult rhesus macaques. Tau-immunoreactivity (-ir), including both 3R and 4R isoforms, was observed throughout the brain, with varying regional intensities. The anterior cingulate cortex, entorhinal cortex, and hippocampus displayed the most robust tau-ir, while the subthalamic nucleus and white matter regions had minimal expression. Tau was present in neurons of gray matter regions; it was preferentially observed in fibers of the globus pallidus and substantia nigra and in cell bodies of the thalamus and subthalamic nucleus. In white matter regions, tau was abundantly present in oligodendrocytes. Additionally, neuronal pThr231-tau-ir was abundant in all brain regions, but not AT8-ir. Differences in regional and intracellular protein expression were not detected between control subjects and both brain hemispheres of MPTP-treated animals. Specifically, tau-ir in the substantia nigra of all subjects colocalized with GABAergic neurons. Overall, this report provides an in-depth characterization of tau expression in the rhesus macaque brain to facilitate future investigations for understanding and modeling tau pathology in this species.

MP01-02 PROTEOMIC ANALYSIS OF SEMINAL FLUID IN RHESUS MACAQUES EXPOSED TO DELTA-9-TETRAHYDROCANNABINOL

You have accessJournal of UrologyCME1 Apr 2023MP01-02 PROTEOMIC ANALYSIS OF SEMINAL FLUID IN RHESUS MACAQUES EXPOSED TO DELTA-9-TETRAHYDROCANNABINOL Jasper C. Bash, Lyndsey E. Shorey-Kendrick, Carol B. Hannah, Charles A. Easley, Eliot Spindel, Jamie O. Lo, and Jason C. Hedges Jasper C. BashJasper C. Bash More articles by this author , Lyndsey E. Shorey-KendrickLyndsey E. Shorey-Kendrick More articles by this author , Carol B. HannahCarol B. Hannah More articles by this author , Charles A. EasleyCharles A. Easley More articles by this author , Eliot SpindelEliot Spindel More articles by this author , Jamie O. LoJamie O. Lo More articles by this author , and Jason C. HedgesJason C. Hedges More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003212.02AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Cannabis use has been associated with male infertility, but the etiology is not well understood. Seminal fluid is comprised of multiple factors (e.g. proteins), that influence fertility. Our objective was to determine the impact of chronic delta-9-tetrahydrocannabinol (THC) use on the seminal fluid proteome in a rhesus macaque (RM) model. METHODS: 6 adult RMs were given a daily THC edible over 280 days (∼4 spermatogenesis cycles) with serial non-sedated semen collection. Differential expression of proteins in the seminal fluid at baseline (pre-THC), high-THC dose (2.5 mg/7 kg/day), and post-THC discontinuation for 140 days (∼2 spermatogenesis cycles) was evaluated. Proteomic analysis was performed by liquid chromatography tandem mass spectrometry followed by statistical analysis to identify differentially expressed proteins. RESULTS: Proteomic analysis resulted in 1,395 quantifiable proteins (Figure 1A). The average percent identity was 88.6% (SD=14.9%). All RM proteins were matched to human proteins with 99.4% of the RM proteins (1,386) exceeding an identity cutoff of 44.3% (average minus 3 SDs). 7 proteins reached FDR significance in any contrast, thus we focused downstream analyses on nominally significant candidate proteins. Ingenuity Pathway Analysis (Figure 1B) revealed that high-THC exposure was associated with dysregulation of pathways related to “Remodeling of Epithelial Adherens Junctions”, “Axonal Guidance Signaling”, and “Glucocorticoid Receptor Signaling”. THC discontinuation for 140 days was associated with decreased “LXR/RXR Activation”, “Acute Phase Response Signaling”, and “Production of Nitric Oxide and ROS in Macrophages”. 5 proteins dysregulated with THC and significantly restored to baseline included products of CHIT1, FGG, MMP9, TGFBI, and CFB genes (Figure 1D). CHIT1 has been associated with oligozoospermia and MMP9 protein with sperm motility. CONCLUSIONS: This study demonstrated the translational strength of the RM model to study male reproductive health; there was significant seminal fluid proteome homology between humans and RMs. THC-exposed RMs are likely to exhibit proteins in their seminal ejaculate that are involved in regulatory processes that could potentially contribute to male infertility. Source of Funding: OHSU Faculty SEED Award and ASRM Pilot and Exploratory Grant © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e1 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jasper C. Bash More articles by this author Lyndsey E. Shorey-Kendrick More articles by this author Carol B. Hannah More articles by this author Charles A. Easley More articles by this author Eliot Spindel More articles by this author Jamie O. Lo More articles by this author Jason C. Hedges More articles by this author Expand All Advertisement PDF downloadLoading ...

MP01-06 DELTA-9-TETRAHYDROCANNABINOL USE ALTERS SPERM DNA METHYLATION IN RHESUS MACAQUES

You have accessJournal of UrologyCME1 Apr 2023MP01-06 DELTA-9-TETRAHYDROCANNABINOL USE ALTERS SPERM DNA METHYLATION IN RHESUS MACAQUES Jason Hedges, Lyndsey Shorey-Kendrick, Carol Hanna, Jasper Bash, Eliot Spindel, Charles Easley, Susan Murphy, and Jamie Lo Jason HedgesJason Hedges More articles by this author , Lyndsey Shorey-KendrickLyndsey Shorey-Kendrick More articles by this author , Carol HannaCarol Hanna More articles by this author , Jasper BashJasper Bash More articles by this author , Eliot SpindelEliot Spindel More articles by this author , Charles EasleyCharles Easley More articles by this author , Susan MurphySusan Murphy More articles by this author , and Jamie LoJamie Lo More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003212.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Cannabis is the most commonly used drug by reproductive age males. Our objective was to determine the effect of chronic delta-9-tetrahydrocannabinol (THC) use on the sperm epigenome and whether these changes are permanent or temporary with discontinuation of THC in a rhesus macaque (RM) model. METHODS: We performed whole genome bisulfite sequencing (WGBS) of DNA extracted from sperm collected from 6 adult RM at baseline (pre-THC), at a high-THC dose (2.5 mg/7kg/day), and post-THC discontinuation for 140 days (∼2 spermatogenesis cycles). Bioinformatic analysis included QA/QC assessments, alignment to the rhesus reference genome, and identification of differentially methylated regions (DMRs). RESULTS: Overlap of genes annotated to DMRs in our RM following THC with published gene lists of human cannabis users and non-users was more than expected by chance (p=2.00e-82; Figure 1A). Pre-THC vs post-THC DMRs were similarly enriched for genes annotated to methylation differences between pre-cannabis exposure vs. post-cannabis discontinuation in humans (Figure 1B). Pre-THC vs high-THC DMRs annotated to 3,902 unique genes annotated and were significantly enriched for genes previously associated with autism spectrum disorder (ASD) (Figure 1C). We identified 2,759 DMRs between pre-THC and high-THC that intersected DMRs in high-THC vs post-THC sperm samples and demonstrated a reversal in methylation post-THC toward the level of methylation pre-THC (Figure 1D). A smaller number of DMRs between pre-THC and high-THC (n=1,898) did not return to baseline levels after THC abstinence (Figure 1E). Using Ingenuity Pathway Analysis, the top canonical pathway associated with THC and restored to baseline levels was the “synaptogenesis signaling pathway” and top biofunctions included “nervous system development and function” and “tissue development”. Similarly, the 1,898 non-restored DMRs were also enriched for genes in the “synaptogenesis signaling pathway” and “nervous system development and function”, as well as for genes in the “sperm motility” canonical pathway. CONCLUSIONS: Chronic THC use in RM alters genes related to nervous system development and function, and autism spectrum disorder that may impact longterm offspring outcomes. Discontinuation of THC resulted in restored methylation in only a subset of DMRs. Source of Funding: NICHD, NIDA, Silver Family © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e3 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jason Hedges More articles by this author Lyndsey Shorey-Kendrick More articles by this author Carol Hanna More articles by this author Jasper Bash More articles by this author Eliot Spindel More articles by this author Charles Easley More articles by this author Susan Murphy More articles by this author Jamie Lo More articles by this author Expand All Advertisement PDF downloadLoading ...

Cellular Localization and Distribution of TGF-β1, GDNF and PDGF-BB in the Adult Primate Central Nervous System.

The available data on the localization of transforming growth factor beta1 (TGF-β1), glial cell line-derived neurotrophic factor (GDNF), and platelet-derived growth factor-BB (PDGF-BB) in the adult primate and human central nervous system (CNS) are limited and lack comprehensive and systematic information. This study aimed to investigate the cellular localization and distribution of TGF-β1, GDNF, and PDGF-BB in the CNS of adult rhesus macaque (Macaca mulatta). Seven adult rhesus macaques were included in the study. The protein levels of TGF-β1, PDGF-BB, and GDNF in the cerebral cortex, cerebellum, hippocampus, and spinal cord were analyzed by western blotting. The expression and location of TGF-β1, PDGF-BB, and GDNF in the brain and spinal cord was examined by immunohistochemistry and immunofluorescence staining, respectively. The mRNA expression of TGF-β1, PDGF-BB, and GDNF was detected by in situ hybridization. The molecular weight of TGF-β1, PDGF-BB, and GDNF in the homogenate of spinal cord was 25 KDa, 30 KDa, and 34 KDa, respectively. Immunolabeling revealed GDNF was ubiquitously distributed in the cerebral cortex, hippocampal formation, basal nuclei, thalamus, hypothalamus, brainstem, cerebellum, and spinal cord. TGF-β1 was least distributed and found only in the medulla oblongata and spinal cord, and PDGF-BB expression was also limited and present only in the brainstem and spinal cord. Besides, TGF-β1, PDGF-BB, and GDNF were localized in the astrocytes and microglia of spinal cord and hippocampus, and their expression was mainly found in the cytoplasm and primary dendrites. The mRNA of TGF-β1, PDGF-BB, and GDNF was localized to neuronal subpopulations in the spinal cord and cerebellum. These findings suggest that TGF-β1, GDNF and PDGF-BB may be associated with neuronal survival, neural regeneration and functional recovery in the CNS of adult rhesus macaques, providing the potential insights into the development or refinement of therapies based on these factors.

Cessation of chronic delta-9-tetrahydrocannabinol use partially reverses impacts on male fertility and the sperm epigenome in rhesus macaques

To determine whether discontinuation of delta-9-tetrahydrocannabinol (THC) use mitigates THC-associated changes in male reproductive health using a rhesus macaque model of daily THC edible consumption. Research animal study. Research institute environment. Adult male rhesus macaques (age, 8-10 years; n = 6). Chronic daily THC edible administration at medically and recreationally relevant contemporary doses followed by cessation of THC use. Testicular volume, serum male hormones, semen parameters, sperm deoxyribonucleic acid (DNA) fragmentation, seminal fluid proteomics, and whole genome bisulfite sequencing of sperm DNA. Chronic THC use resulted in significant testicular atrophy, increased gonadotropin levels, decreased serum sex steroid levels, changes in seminal fluid proteome, and increased DNA fragmentation with partial recovery after discontinuation of THC use. For every increase of 1 mg/7 kg/day in THC dosing, there was a significant decrease in the total testicular volume bilaterally by 12.6 cm3 (95% confidence interval [CI], 10.6-14.5), resulting in a 59% decrease in volume. With THC abstinence, the total testicular volume increased to 73% of its original volume. Similarly, with THC exposure, there were significant decreases in the mean total testosterone and estradiol levels and a significant increase in the follicle-stimulating hormone level. With increasing THC dose, there was a significant decrease in the liquid semen ejaculate volume and weight of coagulum; however, no other significant changes in the other semen parameters were noted. After discontinuing THC use, there was a significant increase in the total serum testosterone level by 1.3 ng/mL (95% CI, 0.1-2.4) and estradiol level by 2.9 pg/mL (95% CI, 0.4-5.4), and the follicle-stimulating hormone level significantly decreased by 0.06 ng/mL (95% CI, 0.01-0.11). Seminal fluid proteome analysis revealed differential expression of proteins enriched for processes related to cellular secretion, immune response, and fibrinolysis. Whole genome bisulfite sequencing identified 23,558 CpGs differentially methylated in heavy-THC vs. pre-THC sperm, with partial restoration of methylation after discontinuation of THC use. Genes associated with altered differentially methylated regions were enriched for those involved in the development and function of the nervous system. This is the first study demonstrating that discontinuation of chronic THC use in rhesus macaques partially restores adverse impacts to male reproductive health, THC-associated sperm differentially methylated regions in genes important for development, and expression of proteins important for male fertility.

Prevalence and Characteristics of Myopia in Adult Rhesus Macaques in Southwest China.

To investigate the prevalence of myopia in a large cohort of adult rhesus macaques at Yunnan Province in southwest China and describe the characteristics of myopic rhesus macaque eyes. A total of 219 rhesus macaques 14.07 ± 2.72 years old (range, 8-21) were randomly recruited for this study. We performed fundus photography and measurements of cycloplegic refractive error (RE) and axial length (AL) on macaques. A total of 429 eyes of 219 macaques were examined. The median RE was -1.25 diopters (D), and the median AL was 18.69 mm. The prevalence of myopia was 62.47%, and one-third of the myopic eyes were highly myopic. The presence of fundus tessellations was higher in myopic eyes than non-myopic eyes (42.54% vs. 6.21%). The cutoff value for the presence of tessellations was -3.52 D for RE and 19.38 mm for AL. In myopic eyes, there were significant differences between grade 1 and grade 3 fundus tessellations on RE (-5.57 ± 2.97 D vs. -8.13 ± 3.51 D) and AL (19.66 ± 0.55 mm vs. 20.60 ± 1.06 mm). Beta-peripapillary atrophy (β-PPA) was found in 48.10% of myopic eyes and 6.83% of non-myopic eyes. The presence of β-PPA is associated with the presence of fundus tessellations, AL, and RE. The presence of β-PPA was higher in grade 3 than grade 1 fundus tessellations (94.4% vs. 76%). More than half of adult rhesus macaques in southwest China are myopic, and one-third of the myopic ones are highly myopic. Similar to humans, tessellated fundi and β-PPA are the characteristic signs of myopic rhesus macaques. Adult rhesus macaques are optimal animal models for research on the pathogenesis of myopia. This study not only provides a reference for the refractive state and AL in myopic rhesus macaques but also indicates that adult rhesus macaques with spontaneous myopia are optimal animal models for research on the pathogenesis of myopia.

Development, refinement, and characterization of a nonhuman primate critical care environment.

Systemic inflammatory response remains a poorly understood cause of morbidity and mortality after traumatic injury. Recent nonhuman primate (NHP) trauma models have been used to characterize the systemic response to trauma, but none have incorporated a critical care phase without the use of general anesthesia. We describe the development of a prolonged critical care environment with sedation and ventilation support, and also report corresponding NHP biologic and inflammatory markers. Eight adult male rhesus macaques underwent ventilation with sedation for 48-96 hours in a critical care setting. Three of these NHPs underwent "sham" procedures as part of trauma control model development. Blood counts, chemistries, coagulation studies, and cytokines/chemokines were collected throughout the study, and histopathologic analysis was conducted at necropsy. Eight NHPs were intentionally survived and extubated. Three NHPs were euthanized at 72-96 hours without extubation. Transaminitis occurred over the duration of ventilation, but renal function, acid-base status, and hematologic profile remained stable. Chemokine and cytokine analysis were notable for baseline fold-change for Il-6 and Il-1ra (9.7 and 42.7, respectively) that subsequently downtrended throughout the experiment unless clinical respiratory compromise was observed. A NHP critical care environment with ventilation support is feasible but requires robust resources. The inflammatory profile of NHPs is not profoundly altered by sedation and mechanical ventilation. NHPs are susceptible to the pulmonary effects of short-term ventilation and demonstrate a similar bioprofile response to ventilator-induced pulmonary pathology. This work has implications for further development of a prolonged care NHP model.

In Vivo Imaging and Kinetic Modeling of Novel Glycogen Synthase Kinase-3 Radiotracers [11C]OCM-44 and [18F]OCM-50 in Non-Human Primates.

Glycogen synthase kinase 3 (GSK-3) is a potential therapeutic target for a range of neurodegenerative and psychiatric disorders. The goal of this work was to evaluate two leading GSK-3 positron emission tomography (PET) radioligands, [11C]OCM-44 and [18F]OCM-50, in non-human primates to assess their potential for clinical translation. A total of nine PET scans were performed with the two radiotracers using arterial blood sampling in adult rhesus macaques. Brain regional time-activity curves were extracted and fitted with one- and two-tissue compartment models using metabolite-corrected arterial input functions. Target selectivity was assessed after pre-administration of the GSK-3 inhibitor PF-04802367 (PF-367, 0.03-0.25 mg/kg). Both radiotracers showed good brain uptake and distribution throughout grey matter. [11C]OCM-44 had a free fraction in the plasma of 3% at baseline and was metabolized quickly. The [11C]OCM-44 volume of distribution (VT) values in the brain increased with time; VT values from models fitted to truncated 60-min scan data were 1.4-2.9 mL/cm3 across brain regions. The plasma free fraction was 0.6% for [18F]OCM-50 and VT values (120-min) were 0.39-0.87 mL/cm3 in grey matter regions. After correcting for plasma free fraction increases during blocking scans, reductions in regional VT indicated >80% target occupancy by 0.1 mg/kg of PF-367 for both radiotracers, supporting target selectivity in vivo. [11C]OCM-44 and [18F]OCM-50 warrant further evaluation as radioligands for imaging GSK-3 in the brain, though radio-metabolite accumulation may confound image analysis.

Cold Agglutinin Disease in a Rhesus Macaque (Macaca mulatta).

Cold agglutinin disease (CAD) is a condition involving anemia and its related symptoms; it is caused by autoantibodiesthat bind and agglutinate red blood cells in areas susceptible to hypothermia, such as extremities exposed to cold temperatures.CAD is rare, with 5 to 20 human cases per million individuals. In this report, we describe a case of CAD in a previouslyhealthy and experimentally naïve adult Indian rhesus macaque that was housed indoors and presented with blood in theurine. After our observations of hemoglobinuria and anemia led us to suspect CAD, we demonstrated that the macaque'sblood agglutinated at reduced temperatures. We also noticed that the provision of cold foraging treats triggered episodes ofhemoglobinuria. Further investigation revealed that serum from the macaque agglutinated RBCs in vitro with high thermalamplitude (at or below 30 °C) and had an antibody titer of 8 to 32. The serum contained autoantibodies of the immunoglobulinM (IgM) isotype; agglutinins of the IgG isotype were not detected. The cold-dependent IgM autoantibodies in the serum fromthe affected macaque reacted against a common RBC antigen because RBCs collected from other macaques were bound andagglutinated by the affected animal's IgM under cold conditions. This in vitro binding activity was reversible when the testtemperature was returned to normal body temperature (37 °C). These findings demonstrated cold-dependent RBC-specific IgMagglutinins and led us to a diagnosis of CAD. This is the first documented case of spontaneous CAD in a rhesus macaque.

Genome-Wide DNA Methylation Profile Indicates Potential Epigenetic Regulation of Aging in the Rhesus Macaque Thymus.

We analyzed whole-genome bisulfite sequencing (WGBS) and RNA sequencing data of two young (1 year old) and two adult (9 years old) rhesus macaques (Macaca mulatta) to characterize the genomic DNA methylation profile of the thymus and explore the molecular mechanism of age-related changes in the thymus. Combining the two-omics data, we identified correlations between DNA methylation and gene expression and found that DNA methylation played an essential role in the functional changes of the aging thymus, especially in immunity and coagulation. The hypomethylation levels of C3 and C5AR2 and the hypermethylation level of C7 may lead to the high expressions of these genes in adult rhesus macaque thymuses, thus activating the classical complement pathway and the alternative pathway and enhancing their innate immune function. Adult thymuses had an enhanced coagulation pathway, which may have resulted from the hypomethylation and upregulated expressions of seven coagulation-promoting factor genes (F13A1, CLEC4D, CLEC4E, FCN3, PDGFRA, FGF2 and FGF7) and the hypomethylation and low expression of CPB2 to inhibit the degradation of blood clots. Furthermore, the functional decline in differentiation, activation and maturation of T cells in adult thymuses was also closely related to the changes in methylation levels and gene expression levels of T cell development genes (CD3G, GAD2, ADAMDEC1 and LCK) and the thymogenic hormone gene TMPO. A comparison of the age-related methylated genes among four mammal species revealed that most of the epigenetic clocks were species-specific. Furthermore, based on the genomic landscape of allele-specific DNA methylation, we identified several age-related clustered sequence-dependent allele-specific DNA methylated (cS-ASM) genes. Overall, these DNA methylation patterns may also help to assist with understanding the mechanisms of the aging thymus with the epigenome.

Vitrectomy and ILM peeling in rhesus macaque: pitfalls and tips for success.

The non-human primate (NHP) model is ideal for pre-clinical testing of novel therapies for human retinal diseases due to its similarity to the human visual system. However, intra-ocular delivery of gene therapy or cell transplantation to the retina gets hampered by the sticky vitreous body and poorly permeable inner limiting membrane (ILM) in primates. Although vitrectomy and ILM peeling are commonly performed in patients, many pitfalls exist in carrying out these procedures in the rhesus macaque, which have not been reported previously. We summarised common surgical pitfalls after performing vitrectomy and ILM peeling in four eyes of two rhesus macaques (one male and one female). We provided corresponding hands-on technical tips based on our surgical experience and literature search. Orbital CT scans were compared between adult rhesus macaques and humans. High-resolution surgical videos were recorded to demonstrate each critical surgical step. Due to size difference, poor post-operative compliance, and high-standard requirements of a controlled experiment, there were eleven common surgical pitfalls during vitrectomy and ILM peeling in rhesus macaque. Falling into these pitfalls may produce discomfort, add fatigue, cause surgical complications, or even lead to the exclusion of the NHP from an experimental group. Recognition and circumvention of these pitfalls during vitrectomy and ILM peeling in NHP are essential. By focusing on these surgical pitfalls, we can better carry out preclinical tests of novel therapies for retinal diseases in the NHP model.

Transcriptional mapping of the macaque retina and RPE-choroid reveals conserved inter-tissue transcription drivers and signaling pathways.

The macula and fovea comprise a highly sensitive visual detection tissue that is susceptible to common disease processes like age-related macular degeneration (AMD). Our understanding of the molecular determinants of high acuity vision remains unclear, as few model organisms possess a human-like fovea. We explore transcription factor networks and receptor-ligand interactions to elucidate tissue interactions in the macula and peripheral retina and concomitant changes in the underlying retinal pigment epithelium (RPE)/choroid. Poly-A selected, 100bp paired-end RNA-sequencing (RNA-seq) was performed across the macular/foveal, perimacular, and temporal peripheral regions of the neural retina and RPE/choroid tissues of four adult Rhesus macaque eyes to characterize region- and tissue-specific gene expression. RNA-seq reads were mapped to both the macaque and human genomes for maximum alignment and analyzed for differential expression and Gene Ontology (GO) enrichment. Comparison of the neural retina and RPE/choroid tissues indicated distinct, contiguously changing gene expression profiles from fovea through perimacula to periphery. Top GO enrichment of differentially expressed genes in the RPE/choroid included cell junction organization and epithelial cell development. Expression of transcriptional regulators and various disease-associated genes show distinct location-specific preference and retina-RPE/choroid tissue-tissue interactions. Regional gene expression changes in the macaque retina and RPE/choroid is greater than that found in previously published transcriptome analysis of the human retina and RPE/choroid. Further, conservation of human macula-specific transcription factor profiles and gene expression in macaque tissues suggest a conservation of programs required for retina and RPE/choroid function and disease susceptibility.

Real-time brain-machine interface in non-human primates achieves high-velocity prosthetic finger movements using a shallow feedforward neural network decoder

Despite the rapid progress and interest in brain-machine interfaces that restore motor function, the performance of prosthetic fingers and limbs has yet to mimic native function. The algorithm that converts brain signals to a control signal for the prosthetic device is one of the limitations in achieving rapid and realistic finger movements. To achieve more realistic finger movements, we developed a shallow feed-forward neural network to decode real-time two-degree-of-freedom finger movements in two adult male rhesus macaques. Using a two-step training method, a recalibrated feedback intention–trained (ReFIT) neural network is introduced to further improve performance. In 7 days of testing across two animals, neural network decoders, with higher-velocity and more natural appearing finger movements, achieved a 36% increase in throughput over the ReFIT Kalman filter, which represents the current standard. The neural network decoders introduced herein demonstrate real-time decoding of continuous movements at a level superior to the current state-of-the-art and could provide a starting point to using neural networks for the development of more naturalistic brain-controlled prostheses.

Hematological and biochemical reference intervals of wild-caught and inhouse adult Indian rhesus macaques (Macaca mulatta)

BackgroundNonhuman primates are used for research purposes such as studying diseases and drug discovery and development programs. Various clinical pathology parameters are used as biomarkers of disease conditions in biomedical research. Detailed reports of these parameters are not available for Indian-origin rhesus macaques. To meet the increasing need for information, we conducted this study on 121 adult Indian rhesus macaques (57 wild-sourced and 64 inhouse animals, aged 3–7 years). A total of 18 hematology and 18 biochemistry parameters were evaluated and reported in this study. Data from these parameters were statistically evaluated for significance amongst inhouse and wild-born animals and for differences amongst sexes. The reference range was calculated according to C28-A3 guidelines for reporting reference intervals of clinical laboratory parameters.ResultsSource of the animals and sex appeared to have statistically significant effects on reference values and range. Wild-born animals reported higher WBC, platelets, neutrophils, RBC, hemoglobin, HCT, MCV, and total protein values in comparison to inhouse monkeys. Sex-based differences were observed for parameters such as RBCs, hemoglobin, HCT, creatinine, calcium, phosphorus, albumin, and total protein amongst others.ConclusionsThrough this study, we have established a comprehensive data set of reference values and intervals for certain hematological and biochemical parameters which will help researchers in planning, conducting, and interpreting various aspects of biomedical research employing Indian-origin rhesus monkeys.

LBSUN86 Effects Of Hyperandrogenemia And Western-style Diet On Rhesus Macaque Tissue-resident Memory T-cells And Their Potential Role In Controlling Local Inflammation And Insulin Sensitivity

Abstract We have previously demonstrated that the combination of chronic hyperandrogenemia (elevated circulating testosterone; T) and an obesogenic Western-style diet (WSD) exerts synergistic effects on the metabolic and reproductive axis, leading to the development of insulin resistance, visceral obesity, and ovarian dysfunction in female rhesus macaques. The underlying cellular connection between T+WSD treatment and abnormal metabolic and reproductive function is not well understood. Tissue resident-memory T-cells (Trm) have emerged as potent regulators of local inflammation. Thus, we hypothesized that T+WSD treatment drives proinflammatory phenotypic changes in Trm cells. To address this hypothesis, we studied a cohort of adult female rhesus macaque exposed to a low-fat diet and no exogenous T (controls) versus those treated with T+WSD for one year. T+WSD animals became insulin resistant and had higher visceral adiposity than control animals. During the mid-luteal phase, all animals were necropsied and immune cells residing in visceral omental white adipose tissue (OM-WAT), the corpus luteum (CL), the contralateral ovary not containing the CL (OV), endometrium (ENDO), lymph nodes (LN), bone marrow (BM), and peripheral blood mononuclear cells (PBMC) were characterized by flow cytometry. Non-activated CD4+ and CD8+ naïve/central memory cells expressing CD28 were detected in all tissue examined. However, the tissue retention receptor CD69 was expressed only on CD4+ and CD8+ cells residing in OM-WAT, CL, OV, and ENDO. These Trm subsets expressed high levels of the C-C Motif Chemokine Receptor 5 (CCR5), whose role in inflammation has been previously reported. Combined T+WSD treatment resulted in a significant increase in CD8+ Trm cell populations in OM-WAT. Notably, the frequencies of Trm in OM-WAT were positively correlated with HOMA-IR, the indicator of insulin resistance. Collectively, our data indicate that combined hyperandrogenemia and WSD can lead to selective recruitment or local differentiation of Trm cells in visceral fat. Trm activation in fat may drive the development of a proinflammatory environment that negatively affects adipose metabolic function, leading to altered systemic metabolic parameters (i. e., hyperinsulinemia) that influence ovarian and uterine processes. Future studies are warranted to define how Trm cell-adipocyte interactions affect adipose metabolic processes. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

A novel rhesus macaque model of Huntington's disease recapitulates key neuropathological changes along with motor and cognitive decline.

We created a new nonhuman primate model of the genetic neurodegenerative disorder Huntington's disease (HD) by injecting a mixture of recombinant adeno-associated viral vectors, serotypes AAV2 and AAV2.retro, each expressing a fragment of human mutant HTT (mHTT) into the caudate and putamen of adult rhesus macaques. This modeling strategy results in expression of mutant huntingtin protein (mHTT) and aggregate formation in the injected brain regions, as well as dozens of other cortical and subcortical brain regions affected in human HD patients. We queried the disruption of cortico-basal ganglia circuitry for 30 months post-surgery using a variety of behavioral and imaging readouts. Compared to controls, mHTT-treated macaques developed working memory decline and progressive motor impairment. Multimodal imaging revealed circuit-wide white and gray matter degenerative processes in several key brain regions affected in HD. Taken together, we have developed a novel macaque model of HD that may be used to develop disease biomarkers and screen promising therapeutics.