Selected Grantee Publications
- 486 results found
Neutralizing Antibody Response to SARS‐CoV‐2 Bivalent mRNA Vaccine in SIV‐Infected Rhesus Macaques: Enhanced Immunity to XBB Subvariants by Two‐Dose Vaccination
Faraone, Journal of Medical Virology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38528837/
Researchers have shown that mRNA vaccination is less effective for people with advanced or untreated HIV infection, but data on the efficacy of mRNA vaccination against SARS-CoV-2 in this population are limited. Using rhesus macaques (sex not specified) with simian immunodeficiency virus (SIV), investigators examined the neutralizing antibody (nAb) response to SARS-CoV-2 vaccination. They found that administration of the bivalent vaccine alone can generate robust nAb titers against Omicron subvariants. Additionally, dams that received antiretroviral therapy had lower nAb titers than untreated dams. Overall, these findings highlight the need for further investigations into the nAb response in people with HIV. Supported by ORIP (P51OD011104), NCI, NIAID, NICHD, and NIMH.
SIV Infection Is Associated With Transient Acute-Phase Steatosis in Hepatocytes In Vivo
Derby, Viruses. 2024.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10892327/
Metabolic dysfunction–associated fatty liver disease (MAFLD) in people with HIV has become an increasing concern, but little is known about liver-specific changes underlying HIV-related MAFLD. Using rhesus macaques (sex not specified), researchers examined the timing of pathogenic changes within the liver during simian immunodeficiency virus (SIV) infection. Their findings suggest differential pathologies associated with the acute and chronic phases of infection. This work highlights the early damage inflicted on the liver by SIV/HIV infection and indicates that damage to the hepatocytes plays a specific role. Overall, the authors conclude that therapeutic interventions targeting metabolic function may benefit liver health in people who have recently received an HIV diagnosis. Supported by ORIP (P51OD011107, P51OD011092) and NIAID.
Ultrasoft Platelet-Like Particles Stop Bleeding in Rodent and Porcine Models of Trauma
Nellenbach et al., Science Translational Medicine. 2024.
https://www.science.org/doi/10.1126/scitranslmed.adi4490
Platelet transfusions are the current standard of care to control bleeding in patients following acute trauma, but their use is limited by short shelf life and limited supply. Immunogenicity and contamination risks also are a concern. Using ultrasoft and highly deformable nanogels coupled to fibrin-specific antibody fragments, researchers developed synthetic platelet-like particles (PLPs) as an alternative for immediate treatment of uncontrolled bleeding. They report that PLPs reduced bleeding and facilitated healing of injured tissue in mice, rat, and swine models (sex not specified) for traumatic injury. These findings can inform further translational studies of synthetic PLPs for the treatment of uncontrolled bleeding in a trauma setting. Supported by ORIP (T32OD011130) and NHLBI.
Potent HPIV3-Neutralizing IGHV5-51 Antibodies Identified from Multiple Individuals Show L Chain and CDRH3 Promiscuity
Abu-Shmais et al., Journal of Immunology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38488511/
Human parainfluenza virus 3 fusion glycoprotein (HPIV3 F), responsible for facilitating viral entry into host cells, is a major target of neutralizing antibodies that inhibit infection. More work is needed to understand these dynamics. Researchers characterized the genetic signatures, epitope specificity, neutralization potential, and publicness of HPIV3-specific antibodies identified across multiple individuals. From this work, they identified 12 potently neutralizing antibodies targeting three nonoverlapping epitopes on HPIV3 F. Six of the antibodies used immunoglobulin heavy variable gene, IGHV 5-51. These antibodies used different L chain variable genes (VL) and diverse H chain CDR 3 (CDRH3) sequences. These findings help elucidate the genetic and functional characteristics of HPIV3-neutralizing antibodies and indicate the existence of a reproducible H chain variable–dependent antibody response associated with VL and CDRH3 promiscuity. Supported by ORIP (K01OD036063), NCATS, NCI, NEI, NIAID, and NIDDK.
Murine MHC-Deficient Nonobese Diabetic Mice Carrying Human HLA-DQ8 Develop Severe Myocarditis and Myositis in Response to Anti-PD-1 Immune Checkpoint Inhibitor Cancer Therapy
Racine et al., Journal of Immunology. 2024.
Myocarditis has emerged as a relatively rare but often lethal autoimmune complication of checkpoint inhibitor (ICI) cancer therapy, and significant mortality is associated with this phenomenon. Investigators developed a new mouse model system that spontaneously develops myocarditis. These mice are highly susceptible to myocarditis and acute heart failure following anti-PD-1 ICI-induced treatment. Additionally, the treatment accelerates skeletal muscle myositis. The team performed characterization of cardiac and skeletal muscle T cells using histology, flow cytometry, adoptive transfers, and RNA sequencing analyses. This study sheds light on underlying immunological mechanisms in ICI myocarditis and provides the basis for further detailed analyses of diagnostic and therapeutic strategies. Supported by ORIP (U54OD020351, U54OD030187), NCI, NIA, NIDDK, and NIGMS.
Proof-of-Concept Studies With a Computationally Designed Mpro Inhibitor as a Synergistic Combination Regimen Alternative to Paxlovid
Papini et al., PNAS. 2024.
As the spread and evolution of SARS-CoV-2 continues, it is important to continue to not only work to prevent transmission but to develop improved antiviral treatments as well. The SARS-CoV-2 main protease (Mpro) has been established as a prominent druggable target. In the current study, investigators evaluate Mpro61 as a lead compound, utilizing structural studies, in vitro pharmacological profiling to examine possible off-target effects and toxicity, cellular studies, and testing in a male and female mouse model for SARS-CoV-2 infection. Results indicate favorable pharmacological properties, efficacy, and drug synergy, as well as complete recovery from subsequent challenge by SARS-CoV-2, establishing Mpro61 as a promising potential preclinical candidate. Supported by ORIP (R24OD026440, S10OD021527), NIAID, and NIGMS.
Obesity Causes Mitochondrial Fragmentation and Dysfunction in White Adipocytes Due to RalA Activation
Xia et al., Nature Metabolism. 2024.
https://pubmed.ncbi.nlm.nih.gov/38286821/
This study presents a molecular mechanism for mitochondrial dysfunction as a characteristic trait of obesity. Chronic activation of the small GTPase RalA in inguinal white adipocytes (iWAT), in male mice fed a high-fat diet (HFD) represses energy expenditure by shifting mitochondrial dynamics toward excessive fission, contributing to weight gain and metabolic dysfunction. Targeted deletion of RalA in iWAT attenuated HFD-induced obesity due to increased energy expenditure and mitochondrial oxidative phosphorylation. Mechanistically, RalA dephosphorylates inhibitory Serine637 on fission protein Drp1, leading to excessive fission in adipocytes and mitochondrial fragmentation. Expression of a human homolog of Drp1—DNM1L—in adipose tissue is positively correlated with obesity and insulin resistance. These findings open avenues to investigate RalA-Drp1 axis in energy homeostasis. Supported by ORIP (S10OD023527), NCI, NHLBI, and NIDDK.
Cdk8/CDK19 Promotes Mitochondrial Fission Through Drp1 Phosphorylation and Can Phenotypically Suppress Pink1 Deficiency in Drosophila
Liao et al., Nature Communications. 2024.
https://www.nature.com/articles/s41467-024-47623-8
Pink1 is a mitochondrial kinase implicated in Parkinson’s disease and is conserved among humans, rodents, and flies. In this study, researchers found that Cdk8 in Drosophila (i.e., the orthologue of vertebrate CDK8 and CDK19) promotes the phosphorylation of Drp1 (i.e., a protein required for mitochondrial fission) at the same residue as Pink1. Cdk8 is expressed in both the cytoplasm and nucleus, and neuronal loss of Cdk8 reduces fly life span and causes bang sensitivity and elongated mitochondria in both muscles and neurons. Overexpression of Cdk8 suppresses elevated levels of reactive oxygen species, mitochondrial dysmorphology, and behavioral defects in flies with low levels of Pink1. These findings suggest that Cdk8 regulates Drp1-mediated mitochondrial fission in a similar manner as Pink1 and may contribute to the development of Parkinson’s disease. Supported by ORIP (R24OD022005, R24OD031447, P40OD018537, P40OD010949), NICHD, and NINDS.
Identifying Potential Dietary Treatments for Inherited Metabolic Disorders Using Drosophila Nutrigenomics
Martelli et al., Cell Reports. 2024.
https://www.sciencedirect.com/science/article/pii/S221112472400189X?via%3Dihub=
Inherited metabolic disorders are known to cause severe neurological impairment and child mortality and can sometimes respond to dietary treatment; however, a suitable paradigm for testing diets is lacking for developing effective dietary treatment. In this study, researchers found that 26 of 35 Drosophila amino acid disorder models screened for disease–diet interactions displayed diet-altered development and/or survival. Among these models, researchers showed that dietary cysteine depletion normalizes metabolic profile and rescues development, neurophysiology, behavior, and life span in a model for isolated sulfite oxidase deficiency. These findings demonstrate the value of using Drosophila in studying diet-sensitive metabolic disorders and developing potential dietary therapies. Supported by ORIP (R24OD031447) and NHGRI.
Consistent Survival in Consecutive Cases of Life-Supporting Porcine Kidney Xenotransplantation Using 10GE Source Pigs
Eiseson et al., Nature Communications. 2024.
https://pubmed.ncbi.nlm.nih.gov/38637524/
Xenotransplantation offers potential for addressing organ donor shortages, and the U.S. Food and Drug Administration recently issued guidance on a regulatory path forward. Researchers have performed studies in this area, but concerns have been expressed about safe clinical translation of their results (e.g., survival, preclinical procurement, immunosuppression, clinical standards of care). In this study, the authors report consistent survival in consecutive cases of kidney xenotransplantation from pigs (male and female) to baboons (male and female). The authors propose that their findings serve as proof of concept for prevention of xenograft rejection in recipients of genetically modified porcine kidneys. This work offers insights for immunosuppression regimens for first-in-human clinical trials. Supported by ORIP (P40OD024628).