Selected Grantee Publications
Matrikine Stimulation of Equine Synovial Fibroblasts and Chondrocytes Results in an In Vitro Osteoarthritis Phenotype
Gagliardi et al., Journal of Orthopaedic Research. 2025.
https://pubmed.ncbi.nlm.nih.gov/39486895
Advancements in therapy development for osteoarthritis (OA) currently are limited due to a lack of physiologically relevant in vitro models. This study aimed to understand the effect of matrikine stimulation, using human recombinant fibronectin fragment containing domains 7–10 (FN7–10), on equine synovial fibroblasts and chondrocytes. Inflammatory cytokines, chemokines, and matrix degradation genes in equine synovial fibroblasts and chondrocytes were significantly altered in response to FN7–10 stimulation; marked upregulation was observed in interleukin-6 (IL-6), IL-4, IL-10, matrix metalloproteinase 1 (MMP1), MMP3, MMP13, CCL2/MCP1, and CXCL6/GCP-2 gene expression. Only IL-6 protein production was significantly increased in media isolated from cells stimulated with FN7–10. These results support the potential use of equine synovial fibroblasts and chondrocytes—employing FN7–10—as representative in vitro models to study OA. Supported by ORIP (T32OD011130) and NIAMS.
Biocompatibility and Bone Regeneration by Shape Memory Polymer Scaffolds
Gasson et al., Journal of Biomedical Materials Research Part A. 2025.
https://pubmed.ncbi.nlm.nih.gov/39404147
This study evaluates the potential of shape memory polymer (SMP) scaffolds for bone tissue engineering, focusing on their biocompatibility and ability to support bone regeneration. Researchers first demonstrated biocompatibility of SMP scaffolds in 12-week-old male Wistar rats and confirmed cell adhesion, proliferation, and differentiation, while promoting bone regeneration in 6 month-old male New Zealand white rabbits with induced bone defects. These scaffolds combine mechanical strength with the capacity to enhance biological healing, making them a promising tool for orthopedic applications. These findings highlight the potential of SMPs as a versatile platform for tissue engineering applications, combining structural support with biocompatibility to enhance bone repair and healing outcomes. Supported by ORIP (T32OD011083).
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.
The Buoyancy of Cryptococcal Cells and Its Implications for Transport and Persistence of Cryptococcus in Aqueous Environments
Jimenez et al., mSphere. 2024.
https://pubmed.ncbi.nlm.nih.gov/39601568/
Cryptococcosis is a major fungal pathogen that causes life-threatening infections. Researchers discovered that Cryptococcus has unique buoyancy properties that help with its survival and spread through water transport. This study explores how these fungal cells remain suspended in liquid, potentially enhancing their ability to survive in their surroundings and infect new hosts. Understanding the role of cellular buoyancy in Cryptococcus transport could improve strategies to prevent spread in aqueous settings, offering new insights into fungal infection risks. Supported by ORIP (T32OD011089), NIAID, and NHLBI.
Three Novel Neoplasms in Nancy Ma's Owl Monkeys (Aotus nancymaae)
Bacon et al., Veterinary Pathology. 2024.
https://pubmed.ncbi.nlm.nih.gov/39692093/
Researchers have identified three previously unreported tumor types in male and female Nancy Ma’s owl monkeys (Aotus nancymaae), a nonhuman primate species that is rarely associated with tumors. Although past cases in owl monkeys were mostly linked to Herpesvirus saimiri–induced lymphoma, this research expands the understanding of tumor development in this species. These findings highlight potential new disease patterns and could inform veterinary care and biomedical research involving owl monkeys. Continued monitoring and investigation of tumors in New World primates are crucial for ensuring animal welfare and research integrity. Supported by ORIP (T32OD011083).
Transcriptomic and Genetic Profiling in a Spontaneous Non-Human Primate Model of Hypertrophic Cardiomyopathy and Sudden Cardiac Death
Rivas et al., Scientific Reports. 2024.
https://pubmed.ncbi.nlm.nih.gov/39733099/
Approximately 1 in 500 individuals are affected by hypertrophic cardiomyopathy (HCM). HCM is characterized by increased left ventricular wall thickness, diastolic dysfunction, and myocardial fibrosis. Outcomes of HCM range from arrhythmias and thromboembolic complications to sudden cardiac death. A current knowledge gap is in understanding the genetic cause of HCM. Researchers compared a nonhuman primate rhesus macaque HCM model to an adult human cohort data set and found that they shared 215 upregulated differentially expressed genes (DEGs); 40 downregulated DEGs; and enriched gene ontology terms, including cardiac muscle cell contraction and heart contraction. The molecular similarity in transcriptomic signatures could be used to develop novel drug therapies to treat HCM in patients. Supported by ORIP (P51OD011107, T32OD011147), NCATS, and NHLBI.
SREBP-Dependent Regulation of Lipid Homeostasis Is Required for Progression and Growth of Pancreatic Ductal Adenocarcinoma
Ishida et al., Cancer Research Communications. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11444119
Lipids are crucial for tumor cell proliferation, and sterol regulatory element-binding protein (SREBP) activation drives lipid synthesis and uptake to maintain cancer growth. This study investigated the role of the SREBP pathway and its regulator, SREBP cleavage–activating protein (SCAP), in lipid metabolism during the development and progression of pancreatic ductal adenocarcinoma (PDAC). Using female mouse xenograft models and male and female pancreas-specific Scap knockout transgenic mice, researchers demonstrated that SCAP is essential for PDAC progression in low-nutrient conditions, linking lipid metabolism to tumor growth. These findings highlight SREBP as a key therapeutic target for PDAC, offering potential strategies for improving treatment by disrupting cancer-associated metabolic reprogramming. Supported by ORIP (T32OD011089), NCI, NHLBI, and NIGMS.
SIV-Specific Antibodies Protect Against Inflammasome-Driven Encephalitis in Untreated Macaques
Castell et al., Cell Reports. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11552693
Viral infections are the most common infectious cause of encephalitis, and simian immunodeficiency virus (SIV)–infected macaques are a well-established model for HIV. Researchers investigated the protective effects of SIV-specific antibodies against inflammation-driven encephalitis in using untreated, SIV-infected, male and female pigtail and rhesus macaques. Findings indicate that these antibodies reduce neuroinflammation and encephalitis, highlighting the importance of antibodies in controlling neuroimmune responses, especially in the absence of antiretroviral therapy. This study provides insight into immune-modulatory approaches to combating inflammation-driven encephalopathies. Supported by ORIP (U42OD013117, T32OD011089), NIDA, NHLBI, NIAID, NINDS, and NIMH.
Extracted Plasma Cell-Free DNA Concentrations Are Elevated in Colic Patients With Systemic Inflammation
Bayless et al., Veterinary Sciences. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11435807
Researchers investigated cell-free DNA (cfDNA) as a potential biomarker to detect colic in humans. In horses, colic is a life-threatening gastrointestinal (GI) condition. Measurements of cfDNA released from damaged or dying cells in the blood of male and female horses with colic were compared across groups based on GI disease type, signs of inflammation, and survival status. Elevated cfDNA levels were prominent in horses with systemic inflammation, but did not significantly differ by GI disease type or survival. This study suggests that cfDNA may be linked to inflammatory responses in colic conditions. Supported by ORIP (T32OD011130).
A Comparative Review of Cytokines and Cytokine Targeting in Sepsis: From Humans to Horses
Hobbs et al., Cells. 2024.
https://pubmed.ncbi.nlm.nih.gov/39273060
Bacterial infections resulting in endotoxin or exotoxin exposure can lead to sepsis because of dysregulated host responses. Sepsis causes organ dysfunction that can lead to death if not treated immediately, yet no proven pharmacological treatments exist. Horses can serve as a comparative and translational model for sepsis in humans because both species share mechanisms of immune response, including severe neutropenia, cytokine storms, formation of neutrophil extracellular traps, and decreased perfusion. Research on sepsis has focused on the pathophysiological role of interleukin-6, interleukin-1β, tumor necrosis factor-α, and interleukin10. Research on novel sepsis therapies has focused on monoclonal antibodies, cytokine antagonists, and cytokine removal through extracorporeal hemoperfusion. Future sepsis research should focus on optimizing therapeutic strategies of cytokine modulation and analyzing the underlying mechanisms of cytokine dysregulation. Supported by ORIP (T32OD011130).