Selected Grantee Publications
- Clear All
- 33 results found
- nidcr
- ninds
- Vaccines/Therapeutics
Senescent-like Microglia Limit Remyelination Through the Senescence Associated Secretory Phenotype
Gross et al., Nature Communications. 2025.
https://www.nature.com/articles/s41467-025-57632-w
Multiple sclerosis (MS) is a chronic, immune-mediated demyelinating disease in which immune cells infiltrate the central nervous system and promote deterioration of myelin and neurodegeneration. The capacity to regenerate myelin in the central nervous system diminishes with age. In this study, researchers used 2- to 3-month-old (young), 12-month-old (middle-aged), and 18- to 22-month-old (aged) C57BL/6 male and female mice. Results showed an upregulation of the senescence marker P16ink4a (P16) in microglial and macrophage cells within demyelinated lesions. Notably, treatment of senescent cells using genetic and pharmacological senolytic methods leads to enhanced remyelination in young and middle-aged mice but fails to improve remyelination in aged mice. These results suggest that therapeutic targeting of senescence-associated secretory phenotype components may improve remyelination in aging and MS. Supported by ORIP (R24OD036199), NIA, NINDS, and NIMH.
A Switch from Glial to Neuronal Gene Expression Alterations in the Spinal Cord of SIV-Infected Macaques on Antiretroviral Therapy
Mulka et al., Journal of Neuroimmune Pharmacology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38862787/
Up to one-third of patients with HIV experience HIV-associated peripheral neuropathy, affecting sensory pathways in the spinal cord. Spinal cord sampling is limited in people with HIV. Researchers examined gene expression alterations in the spinal cords of simian immunodeficiency virus (SIV)-infected male pigtail macaques with and without antiretroviral therapy (ART), using RNA sequencing at key time points throughout infection. Results indicate a shift from glial cell-associated pathways to neuronal pathways in SIV-infected animals receiving ART. These findings suggest that neurons, rather than glia, are predominantly involved in ART-related neurotoxicity and offer new insights into therapeutic strategies for maintaining synaptic homeostasis. Supported by ORIP (U42OD013117, T32OD011089) and NINDS.
Integrin αvβ3 Upregulation in Response to Nutrient Stress Promotes Lung Cancer Cell Metabolic Plasticity
Nam, Cancer Research. 2024.
https://pubmed.ncbi.nlm.nih.gov/38588407/
Tumor-initiating cells can survive in harsh environments via stress tolerance and metabolic flexibility; studies on this topic can yield new targets for cancer therapy. Using cultured cells and live human surgical biopsies of non-small cell lung cancer, researchers demonstrated that nutrient stress drives a metabolic reprogramming cascade that allows tumor cells to thrive despite a nutrient-limiting environment. This cascade results from upregulation of integrin αvβ3, a cancer stem cell marker. In mice, pharmacological or genetic targeting prevented lung cancer cells from evading the effects of nutrient stress, thus blocking tumor initiation. This work suggests that this molecular pathway leads to cancer stem cell reprogramming and could be linked to metabolic flexibility and tumor initiation. Supported by ORIP (K01OD030513), NCI, NIGMS, and NINDS.
Lymphoid Tissues Contribute to Plasma Viral Clonotypes Early After Antiretroviral Therapy Interruption in SIV-Infected Rhesus Macaques
Solis-Leal et al., Science Translational Medicine. 2023.
https://pubmed.ncbi.nlm.nih.gov/38091409/
Researchers are interested in better understanding the sources, timing, and mechanisms of HIV rebound that occurs after interruption of antiretroviral therapy (ART). Using rhesus macaques (sex not specified), investigators tracked barcoded simian immunodeficiency virus (SIV) clonotypes over time and among tissues. Among the tissues studied, mesenteric lymph nodes, inguinal lymph nodes, and spleen contained viral barcodes detected in plasma. Additionally, the authors reported that CD4+ T cells harbored the most viral RNA after ART interruption. These tissues are likely to contribute to viral reactivation and rebound after ART interruption, but further studies are needed to evaluate the relative potential contributions from other tissues and organs. Supported by ORIP (P51OD011104, P51OD011133, S10OD028732, S10OD028653), NCI, NIMH, and NINDS.
Antiretroviral Therapy Reveals Triphasic Decay of Intact SIV Genomes and Persistence of Ancestral Variants
Fray et al., Cell Host & Microbe. 2023.
https://doi.org/10.1016/j.chom.2023.01.016
Antiretroviral therapy (ART) halts HIV-1 replication but is not curative; a pool of latently infected CD4+ T cells persists, and viremia rapidly rebounds if ART is stopped. Using an intact proviral DNA assay, researchers characterized quantitative and qualitative changes in CD4+ T cells for 4 years following ART initiation in rhesus macaques of both sexes. They found that viruses replicating at ART initiation had mutations conferring antibody escape, and sequences with large numbers of antibody escape mutations became less abundant at later time points. Together, these findings reveal that the population of simian immunodeficiency virus (SIV)–infected CD4+ T cells is dynamic and provide a framework for evaluating and interpreting intervention trials. Supported by ORIP (R01OD011095), NIAID, and NIDCR.
Very-Long-Chain Fatty Acids Induce Glial-Derived Sphingosine-1-Phosphate Synthesis, Secretion, and Neuroinflammation
Chung et al., Cell Metabolism. 2023.
https://pubmed.ncbi.nlm.nih.gov/37084732/
Very-long-chain fatty acids (VLCFAs) are the most abundant fatty acids in myelin. During age‑associated degeneration of myelin, glia are exposed to increased levels of VLCFAs. Investigators previously described a novel phenotype in patients that harbors a novel variant in the peroxisomal enzyme ACOX1. Here, they report that that glial loss of ACOX1 leads to an increase of VLCFAs, which results in a concomitant increase in sphingosine-1-phosphate (S1P). They found that suppressing S1P function attenuates the pathological phenotypes caused by excess VLCFAs. This work suggests that lowering of VLCFAs and S1P could be applied as a treatment avenue for multiple sclerosis. Supported by ORIP (R24OD022005, R24OD031447, P40OD018537), NINDS, and NICHD
HIV-1 Remission: Accelerating the Path to Permanent HIV-1 Silencing
Lyons et al., c. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10674359/
Current HIV treatment strategies are focused on forced proviral reactivation and elimination of reactivated cells with immunological or toxin-based technologies. Researchers have proposed the use of a novel “block-lock-stop” approach, which entails the long-term durable silencing of viral expression and permanent transcriptional deactivation of the latent provirus. In the present study, the authors present this approach and its rationale. More research is needed to understand the (1) epigenetic architecture of integrated provirus, (2) cell types and epigenetic cell states that favor viral rebound, (3) molecular functions of Tat (a protein that controls transcription of HIV) and host factors that prevent permanent silencing, (4) human endogenous retrovirus silencing in the genome, and (5) approaches to generate defective proviruses. Additionally, community engagement is crucial for this effort. Supported by ORIP (K01OD031900), NIAID, NCI, NIDA, NIDDK, NHLBI, NIMH, and NINDS.
Timing of Initiation of Anti-Retroviral Therapy Predicts Post-Treatment Control of SIV Replication
Pinkevych et al., PLOS Pathogens. 2023.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10558076/
Researchers are interested in approaches to reducing viral rebound following interruption of antiretroviral therapy, but more work is needed to understand major factors that determine the viral “setpoint” level. Researchers previously assessed how timing of treatment can affect the frequency of rebound from latency. In the current study, the authors analyzed data from multiple studies of simian immunodeficiency virus (SIV) infection in rhesus macaques to further explore the dynamics and predictors of post-treatment viral control. They determined that the timing of treatment initiation was a major predictor of both the level and the duration of post-rebound SIV control. These findings could help inform future treatments. Supported by ORIP (U42OD011023, P51OD011132, P51OD011092), NIAID, NCI, NIDA, NIDDK, NHLBI, NIMH, and NINDS
The Latent Reservoir of Inducible, Infectious HIV-1 Does Not Decrease Despite Decades of Antiretroviral Therapy
McMyn et al., The Journal of Clinical Investigation. 2023.
https://www.doi.org/10.1172/JCI171554
Antiretroviral therapy (ART) does not eliminate the latent HIV reservoir, but it is unknown whether sustained reservoir decay occurs with long-term ART. Researchers used a quantitative viral outgrowth assay, an intact proviral DNA assay, and proviral sequencing to characterize the latent reservoir in men and women with HIV who had maintained suppression of viral replication on ART for 14 to 27 years. They found that the reservoir decay did not continue with long-term ART. Further studies could provide insight into the mechanism underlying these findings. These results reinforce the need for lifelong ART and indicate that the reservoir remains a major barrier to an HIV-1 cure. Supported by ORIP (R01OD011095), NIAID, and NIDCR.
Antiretroviral Therapy Ameliorates Simian Immunodeficiency Virus–Associated Myocardial Inflammation by Dampening Interferon Signaling and Pathogen Response in the Heart
Robinson et al., The Journal of Infectious Diseases. 2023.
https://doi.org/10.1093/infdis/jiad105
HIV is associated with increased risk of cardiovascular disease, but the underlying mechanisms are not fully understood. Using RNA sequencing, investigators characterized the effects of simian immunodeficiency virus (SIV) infection on the hearts of male rhesus macaques. They demonstrated that SIV infection drives a canonical antiviral response in the heart, as well as dysregulation of genes involved in fatty acid shuttling and metabolism. Their findings suggest that antiretroviral therapy helps mitigate immune activation during viremic conditions and plays a cardioprotective role. Future studies are needed to assess the long-term effects of these dynamics. Supported by ORIP (P51OD011104), NIAID, NIMH, and NINDS.