Selected Grantee Publications
Duration of Antiretroviral Therapy Impacts the Degree of Residual SIV Infection in the Gut in Long‐Term Non‐Progressing Chinese Rhesus Macaques
Solis-Leal et al., Journal of Medical Virology. 2023.
https://onlinelibrary.wiley.com/doi/abs/10.1002/jmv.28185
HIV and simian immunodeficiency virus (SIV) reservoirs have been shown to persist with antiretroviral therapy (ART), particularly in the gut‐associated lymphoid tissues in the intestine. The effects of ART on the reservoir size, however, had not been explored fully. In this study, researchers used male Chinese‐origin rhesus macaques to assess the effects of long- and short-term ART on gut infection—across segments of the small and large intestines—in long‐term non‐progressors (LTNPs). They reported that although ART does not eliminate SIV in LTNPs, a longer ART period dramatically reduces SIV infection and diversity in the gut. Further studies are needed to better understand the reduction of HIV gut reservoirs in this context. Supported by ORIP (P51OD011133, P51OD011104), NIAID, NIMH, and NINDS.
Promoting Validation and Cross-Phylogenetic Integration in Model Organism Research
Cheng et al., Disease Models & Mechanisms. 2022.
https://www.doi.org/10.1242/dmm.049600
Model organisms are essential for biomedical research and therapeutic development, but translation of such research to the clinic is low. The authors summarized discussions from an NIH virtual workshop series, titled “Validation of Animal Models and Tools for Biomedical Research,” held from 2020 to 2021. They described challenges and opportunities for developing and integrating tools and resources and provided suggestions for improving the rigor, validation, reproducibility, and translatability of model organism research. Supported by ORIP (R01OD011116, R24OD031447, R03OD030597, R24OD018559, R24OD017870, R24OD026591, R24OD022005, U42OD026645, U42OD012210, U54OD030165, UM1OD023221, P51OD011107), NIAMS, NIDDK, NIGMS, NHGRI, and NINDS.
Molecular and Cellular Evolution of the Primate Dorsolateral Prefrontal Cortex
Ma et al., Science. 2022.
https://www.doi.org/10.1126/science.abo7257
The dorsolateral prefrontal cortex (dlPFC) exists only in primates, lies at the center of high-order cognition, and is a locus of pathology underlying many neuropsychiatric diseases. The investigators generated single-nucleus transcriptome data profiling more than 600,000 nuclei from the dlPFC of adult humans, chimpanzees, rhesus macaques, and common marmosets of both sexes. Postmortem human samples were obtained from tissue donors. The investigators’ analyses delineated dlPFC cell-type homology and transcriptomic conservation across species and identified species divergence at the molecular and cellular levels, as well as potential epigenomic mechanisms underlying these differences. Expression patterns of more than 900 genes associated with brain disorders revealed a variety of conserved, divergent, and group-specific patterns. The resulting data resource will help to vertically integrate marmoset and macaque models with human-focused efforts to develop treatments for neuropsychiatric conditions. Supported by ORIP (P51OD011133), NIA, NICHD, NIDA, NIGMS, NHGRI, NIMH, and NINDS.
A Molecularly Integrated Amygdalo-Fronto-Striatal Network Coordinates Flexible Learning and Memory
Li et al., Nature Neuroscience. 2022.
https://www.doi.org/10.1038/s41593-022-01148-9
Behavioral flexibility is critical for navigating dynamic environments and requires the durable encoding and retrieval of new memories to guide future choice. The orbitofrontal cortex (OFC) supports outcome-guided behaviors, but the coordinated neural circuitry and cellular mechanisms by which OFC connections sustain flexible learning and memory are not understood fully. Using a mouse model, researchers demonstrated that the OFC neuronal ensembles store a memory trace for newly learned information. They describe the directional transmission of information within an integrated amygdalo-fronto-striatal circuit across time. Supported by ORIP (P51OD011132), NIDA, NIMH, and NINDS.
Parallel Processing, Hierarchical Transformations, and Sensorimotor Associations along the “Where” Pathway
Doudlah et al., eLife. 2022.
https://www.doi.org/10.7554/eLife.78712
Visually guided behaviors require the brain to transform ambiguous retinal images into object-level spatial representations and map those representations to motor responses. These capabilities are supported by the dorsal “where” pathway in the brain, but the specific contributions of areas along this pathway have remained elusive. Using a rhesus macaque model, researchers compared neuronal activity in two areas along the “where” pathway that bridge the parieto-occipital junction: intermediate visual area V3A and the caudal intraparietal (CIP) area. Neuronal activity was recorded while the animals made perceptual decisions based on judging the tilt of 3D visual patterns. The investigators found that CIP shows higher-order spatial representations and more choice-correlated responses, which support a V3A-to-CIP hierarchy. The researchers also discovered modulation of V3A activity by extraretinal factors, suggesting that V3A might be better characterized as contributing to higher-order behavioral functions rather than low-level visual feature processing. Supported by ORIP (P51OD011106), NEI, NICHD, and NINDS.
Neuroprotective Effects of Electrical Stimulation Following Ischemic Stroke in Non-Human Primates
Zhou et al., Institute of Electrical and Electronics Engineers. 2022.
https://www.doi.org/10.1109/EMBC48229.2022.9871335
Using rhesus macaques of both sexes, researchers identified a novel treatment for ischemic stroke, which occurs when brain cells die due to lack of oxygen. The treatment consisted of applying 60 minutes of electrical brain stimulation shortly after the stroke. The animals that received electrical stimulation had less brain damage, fewer cell deaths, and more protective neural activity patterns than the monkeys that did not receive electrical stimulation. Future work can determine whether this stimulation can be applied noninvasively, as well as how to improve the electrical stimulation patterns to optimize health outcomes for stroke patients. Supported by ORIP (P51OD010425) and NINDS.
Neuroinflammatory Profiling in SIV-Infected Chinese-Origin Rhesus Macaques on Antiretroviral Therapy
Solis-Leal et al., Viruses. 2022.
https://www.doi.org/10.3390/v14010139
The central nervous system (CNS) HIV reservoir contributes to residual neuroimmune activation, which can lead to HIV-associated neurocognitive disorder. Researchers characterized the expression of signaling molecules associated with inflammation in plasma, cerebrospinal fluid, and basal ganglia of Chinese-origin rhesus macaques (sex not specified) with simian immunodeficiency virus (SIV). They reported a correlation between levels of CCL2 in plasma and cerebrospinal fluid, suggesting that researchers could infer the degree of CNS inflammation by testing CCL2 levels in peripheral blood. Overall, these findings provide insight into neuroinflammation and signaling associated with HIV persistence in the CNS. Supported by ORIP (P51OD011104, P51OD011133), NIMH, and NINDS.
Comparative Cellular Analysis of Motor Cortex in Human, Marmoset and Mouse
Bakken et al., Nature. 2021.
https://pubmed.ncbi.nlm.nih.gov/34616062/
Investigators used high-throughput transcriptomic and epigenomic profiling of more than 450,000 single nuclei in humans, marmosets, and mice, to characterize the cellular makeup of the primary motor cortex (M1), which exhibits similarities that mirror evolutionary distance and are consistent between the transcriptome and epigenome. Despite the overall conservation, many species-dependent specializations are apparent. These results demonstrate the robust molecular foundations of cell-type diversity in M1 across mammals and point to the genes and regulatory pathways responsible for the functional identity of cell types and their species-specific adaptations. Supported by ORIP (P51OD010425), NIMH, NCATS, NINDS, and NIDA.
A Novel Non-Human Primate Model of Pelizaeus-Merzbacher Disease
Sherman et al., Neurobiology of Disease. 2021.
https://www.sciencedirect.com/science/article/pii/S096999612100214X
Pelizaeus-Merzbacher disease (PMD) in humans is a severe hypomyelinating disorder of the central nervous system (CNS) linked to mutations in the proteolipid protein-1 (PLP1) gene. Investigators report on three spontaneous cases of male neonatal rhesus macaques (RMs) with clinical symptoms of hypomyelinating disease. Genetic analysis revealed that the parents of these related RMs carried a rare, hemizygous missense variant in exon 5 of the PLP1 gene. These RMs represent the first reported NHP model of PMD, providing an opportunity for studies to promote myelination in pediatric hypomyelinating diseases, as other animal models for PMD do not fully mimic the human disorder. Supported by ORIP (R24OD021324, P51OD011092, and S10OD025002) and NINDS.
MRI Characteristics of Japanese Macaque Encephalomyelitis (JME): Comparison to Human Diseases
Tagge et al., Journal of Neuroimaging. 2021.
https://onlinelibrary.wiley.com/doi/10.1111/jon.12868
Magnetic resonance imaging data (MRI) were obtained from 114 Japanese macaques, including 30 animals of both sexes that presented with neurological signs of Japanese macaque encephalomyelitis (JME). Quantitative estimates of blood-brain barrier permeability to gadolinium-based-contrast agent (GBCA) were obtained in acute, GBCA-enhancing lesions, and longitudinal imaging data were acquired for 15 JME animals. Intense, focal neuroinflammation was a key MRI finding in JME. Several features of JME compare directly to human inflammatory demyelinating diseases. The development and validation of noninvasive imaging biomarkers in JME provides the potential to improve diagnostic specificity and contribute to the understanding of human demyelinating diseases. Supported by ORIP (P51OD011092, S10OD018224), NINDS, and NIBIB.