Selected Grantee Publications
Cannabinoids Modulate the Microbiota–Gut–Brain Axis in HIV/SIV Infection by Reducing Neuroinflammation and Dysbiosis while Concurrently Elevating Endocannabinoid and Indole-3-Propionate Levels
McDew-White et al., Journal of Neuroinflammation. 2023.
https://jneuroinflammation.biomedcentral.com/articles/10.1186/s12974-023-02729-6
Chronic neuroinflammation is thought to be a significant contributor to HIV-associated neurocognitive disorders. Using rhesus macaques of both sexes, researchers investigated the effects of simian immunodeficiency virus (SIV) infection on the microbiota–gut–brain axis (MGBA), as well as the use of low-dose cannabinoids to reverse MGBA dysregulation. They reported that tetrahydrocannabinol reduced neuroinflammation and dysbiosis and increased plasma endocannabinoid, endocannabinoid-like, glycerophospholipid, and indole-3-propionate levels. This study offers a potential strategy to promote brain health in people with HIV. Supported by ORIP (P51OD011104, P51OD011103), NIAID, and NIDA.
Assessment of Anti-CD20 Antibody Pre-Treatment for Augmentation of CAR-T Cell Therapy in SIV-Infected Rhesus Macaques
Pampusch et al., Frontiers in Immunology. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9941136/
Chronic HIV replication occurs primarily within lymphoid follicles, and investigators hypothesized that temporary disruption of these follicles would create space for chimeric antigen receptor (CAR) T cell engraftment and lead to increased abundance and persistence of CAR T cells. They evaluated CAR T cell abundance and persistence in rhesus macaques of both sexes following simian immunodeficiency virus (SIV) infection and antiretroviral therapy suppression. Their results suggest that CAR T cells expanded to a greater extent in the depleted and CAR T cell–treated animals. Further studies are needed to evaluate strategies for engraftment and the persistence of HIV-specific CAR T cells. Supported by ORIP (P51OD011106, P51RR000167), NIAID, and NIDA.
SIV Infection Regulates Compartmentalization of Circulating Blood Plasma miRNAs within Extracellular Vesicles (EVs) and Extracellular Condensates (ECs) and Decreases EV-Associated miRNA-128
Kopcho et al., Viruses. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10059597/
MicroRNAs (miRNAs) are thought to be involved in HIV pathogenesis, but the effect of HIV on the compartmentalization of miRNAs within extracellular particles is unclear. Researchers sequenced the small RNA population of paired EVs and ECs from male rhesus macaques. They showed that extracellular miRNAs in blood plasma are not restricted to any type of extracellular particles but are associated with lipid‑based carriers, with a significant proportion associated with ECs. Further, simian immunodeficiency virus (SIV) infection altered the miRNAome profile of EVs and revealed miR‑128‑3p as a potential target of infection. This work suggests that EV‑ and EC‑associated miRNAs potentially could serve as biomarkers for various diseases. Supported by ORIP (P51OD011104, P51OD011133), NIAID, and NIDA.
Alterations in Abundance and Compartmentalization of miRNAs in Blood Plasma Extracellular Vesicles and Extracellular Condensates during HIV/SIV Infection and its Modulation by Antiretroviral Therapy (ART) and Delta-9-Tetrahydrocannabinol (Δ9-THC)
Kopcho et al., Viruses. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10053514/
MicroRNAs (miRNAs) have been shown to regulate host response to HIV infection. Previously, investigators proposed that the assortment of extracellular miRNAs into distinct carriers could provide a new dimension to miRNA-based biomarkers. In this follow-up study, the investigators used particle purification liquid chromatography to determine the abundance and compartmentalization of blood plasma extracellular miRNAs into extracellular vesicles and extracellular condensates during simian immunodeficiency virus (SIV) infection in male rhesus macaques. They reported that different treatments—combination ART and Δ9‑THC—impart distinct effects on the enrichment and compartmentalization of extracellular miRNAs. These data suggest that the extracellular miRNA profile in blood plasma is altered following SIV infection. Supported by ORIP (P51OD011104, P51OD011133), NIAID, and NIDA.
CD8+ Lymphocytes Do Not Impact SIV Reservoir Establishment under ART
Statzu et al., Nature Microbiology. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9894752/
The HIV-1 latent reservoir has been shown to persist following antiretroviral therapy (ART), but the mechanisms underlying the establishment and maintenance of the reservoir are not fully understood. Using rhesus macaques of both sexes, investigators examined the effects of CD8+ T cells on formation of the latent reservoir with simian immunodeficiency virus (SIV) infection. They found that CD8+ T cell depletion resulted in slower decline of viremia but did not change the frequency of infected CD4+ T cells in the blood or lymph nodes. Additionally, the size of the persistent reservoir was unchanged. These findings suggest that the viral reservoir is established largely independent of SIV-specific cytotoxic T lymphocyte control. Supported by ORIP (P51OD011132), NIAID, NCI, NIDDK, NIDA, NHLBI, 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.
Cannabinoid Control of Gingival Immune Activation in Chronically SIV-Infected Rhesus Macaques Involves Modulation of the Indoleamine-2,3-Dioxygenase-1 Pathway and Salivary Microbiome
McDew-White et al., EBioMedicine. 2021.
https://pubmed.ncbi.nlm.nih.gov/34954656/
HIV-associated periodontal disease (PD) affects people living with HIV (PLWH) on combination anti-retroviral therapy (cART). Researchers used a systems biology approach to investigate the molecular, metabolome, and microbiome changes underlying PD and its modulation by phytocannabinoids (Δ9-THC) in rhesus macaques. Δ9-THC reduced IDO1 protein expression. The findings suggest that phytocannabinoids may help reduce gingival/systemic inflammation, salivary dysbiosis, and potentially metabolic disease in PLWH on cART. Supported by ORIP (P51OD011104, P51OD011133, U42OD010442), NIAID, NIDA, NIDDK, NIDCR, and NIMH.
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.
Advancing Human Disease Research with Fish Evolutionary Mutant Models
Beck et al., Trends in Genetics. 2021.
https://pubmed.ncbi.nlm.nih.gov/34334238/
Model organism research is essential to understand disease mechanisms. However, laboratory-induced genetic models can lack genetic variation and often fail to mimic disease severity. Evolutionary mutant models (EMMs) are species with evolved phenotypes that mimic human disease. They have improved our understanding of cancer, diabetes, and aging. Fish are the most diverse group of vertebrates, exhibiting a kaleidoscope of specialized phenotypes, many that would be pathogenic in humans but are adaptive in the species' specialized habitat. Evolved compensations can suggest avenues for novel disease therapies. This review summarizes current research using fish EMMs to advance our understanding of human disease. Supported by ORIP (R01OD011116), NIA, NIDA, and NIGMS.