Selected Grantee Publications
Suppression of Viral Rebound by a Rev-Dependent Lentiviral Particle in SIV-Infected Rhesus Macaques
Hetrick et al., Gene Therapy. 2025.
https://pubmed.ncbi.nlm.nih.gov/39025983/
Viral reservoirs are a current major barrier that prevents an effective cure for patients with HIV. Antiretroviral therapy (ART) effectively suppresses viral replication, but ART cessation leads to viral rebound due to the presence of viral reservoirs. Researchers conducted in vivo testing of simian immunodeficiency virus (SIV) Rev-dependent vectors in SIVmac239-infected male and female Indian rhesus macaques, 3–6 years of age, to target viral reservoirs. Treatment with the SIV Rev-dependent vector reduced viral rebound and produced neutralizing antibodies following ART cessation. These results indicate the potential to self-control plasma viremia through a neutralizing antibody-based mechanism elicited by administration of Rev-dependent vectors. This research could guide future studies focused on investigating multiple vector injections and quantifying cell-mediated immune responses. Supported by ORIP (P51OD011104, P40OD028116), NIAID, and NIMH.
Single-Cell Transcriptomics Predict Novel Potential Regulators of Acute Epithelial Restitution in the Ischemia-Injured Intestine
Rose et al., American Journal of Physiology-Gastrointestinal and Liver Physiology. 2025.
https://pubmed.ncbi.nlm.nih.gov/39853303
Following ischemia in the small intestine, early barrier restoration relies on epithelial restitution to reseal the physical barrier and prevent sepsis. Pigs share a similar gastrointestinal anatomy, physiology, and microbiota with humans. Researchers used neonatal and juvenile, 2- to 6-week-old male and female Yorkshire cross pigs to determine upstream regulators of restitution. Single-cell sequencing of ischemia-injured epithelial cells demonstrated two sub-phenotypes of absorptive enterocytes, with one subset presenting a restitution phenotype. Colony-stimulating factor-1 (CSF1) was the only predicted upstream regulator expressed in juvenile jejunum compared with neonatal jejunum. An in vitro scratch wound assay using IPEC-J2 cells showed that BLZ945, a colony-stimulating factor 1 receptor antagonist, inhibited restitution. Ex vivo ischemia-injured neonatal pig jejunum treated with exogenous CSF1 displayed increased barrier function. This study could inform future research focused on developing novel therapeutics for intestinal barrier injury in patients. Supported by ORIP (T32OD011130, K01OD028207), NCATS, NICHD, and NIDDK.
Targeting Pancreatic Cancer Cell Stemness by Blocking Fibronectin-Binding Integrins on Cancer-Associated Fibroblasts
Wu et al., Cancer Research Communications. 2025.
https://pubmed.ncbi.nlm.nih.gov/39785683
Cancer-associated fibroblasts (CAFs) stimulate the formation and progression of pancreatic adenocarcinoma (PDAC) through the generation of extracellular matrix (ECM). Researchers developed a bispecific antibody (bsAb) that targets α5β1 and αvβ3 integrins expressed on CAFs. Blockade using the bsAb resulted in reduced assembly of fibronectin and collagen fibers in vitro. An antifibrotic effect was observed when CAFs were plated for 72 hours prior to bsAb treatment; pre-deposited ECM was disrupted. Six- to 8-week-old female nu/nu mice treated with bsAb demonstrated fewer tumors and reduced tumor stiffness compared with those exposed to only CAFs co-injected with PDAC cells. These results support a potential novel PDAC therapeutic that targets CAF-mediated fibronectin assembly and ECM production. Supported by ORIP (K01OD030513) and NCI.
Transiently Boosting Vγ9+Vδ2+ γδ T Cells Early in Mtb Coinfection of SIV-Infected Juvenile Macaques Does Not Improve Mtb Host Resistance
Larson et al., Infection and Immunity. 2024.
https://pubmed.ncbi.nlm.nih.gov/39475292/
Children with HIV have a higher risk of developing tuberculosis (TB), which is caused by the bacterium Mycobacterium tuberculosis (Mtb). This study utilized juvenile Mauritian cynomolgus macaques to investigate whether enhancing Vγ9+Vδ2+ γδ T cells with zoledronate treatment could improve TB resistance in HIV–TB coinfection. Researchers found that although boosting these immune cells temporarily increased their presence, it did not enhance the macaques’ ability to fight Mtb infection. These findings suggest that solely targeting γδ T cells may not be an effective strategy for improving TB immunity in immunocompromised individuals. These insights are crucial for developing better treatments for HIV–TB coinfections. Supported by ORIP (K01OD033539, P51OD011106) and NIAID.
Aberrant Activation of Wound-Healing Programs within the Metastatic Niche Facilitates Lung Colonization by Osteosarcoma Cells
Reinecke et al., Clinical Cancer Research. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11739783/
The leading cause of deaths in the pediatric osteosarcoma is due to lung metastasis. A current clinical need is the development of therapies that disrupt the later stages of metastasis. Researchers used 6- to 8-week-old female C57BL/6 and CB17-SCID mice to understand how tumor cells disrupt the lung microenvironment to promote tumor growth. Single-cell RNA sequencing and spatial transcriptomics demonstrated osteosarcoma–epithelial cell interactions in a chronic state of wound healing in the lung. Nintedanib administration significantly disrupted metastatic progression compared with the vehicle control, demonstrating a potential novel therapeutic for combating osteosarcoma lung metastasis. Supported by ORIP (K01OD031811), NCI, and NCATS.
Response of Spontaneous Oral Tumors in Canine Cancer Patients Treated With Stereotactic Body Radiation Therapy (SBRT)
Gualtieri et al., Radiation Research. 2024.
https://pubmed.ncbi.nlm.nih.gov/39478420
This single-institution retrospective study assessed outcomes in 98 dogs with oral tumors after treatment with SBRT. Overall, progression-free survival (PFS) was 152 days, and median survival time (MST) was 270 days for dogs with oral malignant melanoma, squamous cell carcinoma, and soft tissue sarcoma following SBRT, with no significant differences among the groups. Shortened PFS and MST were associated with lymph node metastasis and the use of elective nodal irradiation. Adverse effects of SBRT were common within the study population and included organ toxicities (11.8%) and the formation of certain fistulas (28.4%). The authors concluded that the presence of these adverse effects warrants a re-evaluation of SBRT risk factors and protocols. Supported by ORIP (K01OD031809).
Immune Gene Regulation Is Associated With Age and Environmental Adversity in a Nonhuman Primate
Watowich et al., Molecular Ecology. 2024.
https://pubmed.ncbi.nlm.nih.gov/39032090
The mammalian aging process involves a decline in physiological function, influenced by molecular mechanisms like epigenetic changes. These processes have been studied in controlled settings, however the role of aging in naturalistic populations remains unclear. This study explored the effects of environmental stressors (i.e., Hurricane Maria) on DNA methylation in free-living male and female rhesus macaques in Cayo Santiago, Puerto Rico. Results showed that environmental adversity accelerated age-related molecular changes, especially in gene transcription regions, while primary aging mainly affected nonregulatory regions. These findings highlight how the biology of aging is influenced by environmental factors. Supported by ORIP (P40OD012217), NIA, and NIMH.
SHIV Remission in Macaques With Early Treatment Initiation and Ultra Long-Lasting Antiviral Activity
Daly et al., Nature Communications. 2024.
https://pubmed.ncbi.nlm.nih.gov/39632836
Antiretroviral therapy (ART) suppresses HIV and simian immunodeficiency virus (SIV) replication but cannot eliminate reservoirs of long-lived infected cells that enable rebound after discontinuation of ART. These researchers hypothesized that ART designed to have long-lasting activity and penetrate tissue reservoirs would be optimized against HIV or SIV remission. Macaques were treated with a four-drug regimen (i.e., oral emtricitabine/tenofovir alafenamide and long-acting cabotegravir/rilpivirine) designed to improve dosing of immune cells, with or without the immune-activating drug vesatolimod (VES), after the onset of SIV viremia. The animals were monitored for 1 year with treatment and 2 additional years following treatment discontinuation. Durable viral suppression was observed in all animals treated with the optimized ART regimen with or without VES. These results will inform novel HIV treatment regimens with long-lasting antiviral activity in humans. Supported by ORIP (P40OD028116).
Mechanical Force of Uterine Occupation Enables Large Vesicle Extrusion From Proteostressed Maternal Neurons
Wang et al., eLife. 2024.
https://pubmed.ncbi.nlm.nih.gov/39255003
This study investigates how mechanical forces from uterine occupation influence large vesicle extrusion (exopher production) from proteostressed maternal neurons in Caenorhabditis elegans. Exophers, previously found to remove damaged cellular components, are poorly understood. Researchers demonstrate that mechanical stress significantly increases exopher release from touch receptor neurons (i.e., ALMR) during peak reproductive periods, coinciding with egg production. Genetic disruptions reducing reproductive activity suppress exopher extrusion, whereas interventions promoting egg retention enhance it. These findings reveal that reproductive and mechanical factors modulate neuronal stress responses, providing insight on how systemic physiological changes affect neuronal health and proteostasis, with broader implications for reproductive-neuronal interactions. Supported by ORIP (R24OD010943, P40OD010440), NIA, and NIGMS.
Proinflammatory Cytokines Suppress Stemness-Related Properties and Expression of Tight Junction in Canine Intestinal Organoids
Nakazawa et al., In Vitro Cellular & Developmental Biology—Animal. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11419940
Cells in the gastrointestinal tract are exposed to numerous stressors that can promote excessive inflammation, including environmental chemicals and dietary substances. Researchers studied how canine intestinal epithelial cell (IEC)–derived organoids responded to exposure to one of three proinflammatory cytokines; interferon-γ (IFN-γ), tumor necrosis factor-α (TNFα), or interleukin-1β (IL1β). Exposure to IFN-γ resulted in downregulation of the stem cell marker Lgr5. Only IFN-γ exposure resulted in increased production of caspase 3 and caspase 8. Exposure to either IFN-γ or IL1β resulted in suppressed cell proliferation. The pro-inflammatory cytokines caused reduced tight junction protein expression and compromised membrane integrity. These findings are important to understanding IEC response to different inflammatory stimuli and to broadening knowledge of gut physiology. Supported by ORIP (K01OD030515, R21OD031903).