Selected Grantee Publications
Indoleamine-2,3-Dioxygenase Inhibition Improves Immunity and Is Safe for Concurrent Use with cART During Mtb/SIV Coinfection
Singh et al., JCI Insight. 2024.
https://pubmed.ncbi.nlm.nih.gov/39114981/
HIV and tuberculosis (TB) coinfection can lead to TB reactivation that is caused by chronic immune system activation. Researchers explored indoleamine-2,3-dioxygenase (IDO) inhibition as a host-directed therapy (HDT) to mitigate immune suppression and TB reactivation in a rhesus macaque Mycobacterium tuberculosis (Mtb)/simian immunodeficiency virus (SIV) model. The IDO inhibitor D-1-methyl tryptophan improved T-cell immunity, reduced tissue damage, and controlled TB-related inflammation without interfering with the efficacy of combinatorial antiretroviral therapy (cART). These findings support IDO inhibition as a potential HDT in HIV/TB coinfection, providing a strategy to balance immune control while preventing TB reactivation in cART-treated patients. Supported by ORIP (S10OD028732, U42OD010442, S10OD028653) and NIAID.
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.
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.
Potent Broadly Neutralizing Antibodies Mediate Efficient Antibody-Dependent Phagocytosis of HIV-Infected Cells
Snow et al., PLOS Pathogens. 2024.
https://pubmed.ncbi.nlm.nih.gov/39466835
This study investigates the role of potent broadly neutralizing antibodies (bNAbs) in mediating antibody-dependent cellular phagocytosis (ADCP) of HIV-infected cells. Researchers developed a novel cell-based approach to assess the ADCP of HIV-infected cells expressing natural conformations of the viral envelope glycoprotein, which allows the virus to infect a host cell. The findings in this study demonstrate that bNAbs facilitate efficient ADCP, highlighting their potential in controlling HIV infection by promoting immune clearance of infected cells. This study provides valuable insights into antibody-mediated immune mechanisms and supports the development of antibody-based therapies and vaccines targeting HIV. Supported by ORIP (P51OD011106) and NIAID.
Extended Survival of 9- and 10-Gene-Edited Pig Heart Xenografts With Ischemia Minimization and CD154 Costimulation Blockade-Based Immunosuppression
Chaban et al., The Journal of Heart and Lung Transplantation. 2024.
https://pubmed.ncbi.nlm.nih.gov/39097214
Heart transplantations are severely constrained from the shortage of available organs derived from human donors. Xenotransplantation of hearts from gene-edited (GE) pigs is a promising way to address this problem. Researchers evaluated GE pig hearts with varying knockouts and human transgene insertions. Human transgenes are introduced to mitigate important physiological incompatibilities between pig cells and human blood. Using a baboon heterotopic cardiac transplantation model, one female and seven male specific-pathogen-free baboons received either a 3-GE, 9-GE, or 10-GE pig heart with an immunosuppression regimen targeting CD40/CD154. Early cardiac xenograft failure with complement activation and multifocal infarcts were observed with 3-GE pig hearts, whereas 9- and 10-GE pig hearts demonstrated successful graft function and prolonged survival. These findings show that one or more transgenes of the 9- and 10-GE pig hearts with CD154 blockade provide graft protection in this preclinical model. Supported by ORIP (U42OD011140) and NIAID.
Impaired Skeletal Development by Disruption of Presenilin-1 in Pigs and Generation of Novel Pig Models for Alzheimer's Disease
Uh et al., Journal of Alzheimer's Disease. 2024.
https://pubmed.ncbi.nlm.nih.gov/39177593/
This study explored the effects of presenilin 1 (PSEN1) disruption on vertebral malformations in male and female PSEN1 mutant pigs. Researchers observed significant skeletal impairments and early deaths in pigs with a PSEN1 null mutation, mirroring phenotypes seen in mouse models of Alzheimer’s disease (AD). This porcine model provides valuable insights into pathological hallmarks of PSEN1 mutations in AD, offering a robust platform of therapeutic exploration. The findings establish pigs as an essential translational model for AD, enabling advanced studies on pathophysiology and treatment development for human skeletal and neurological conditions. Supported by ORIP (U42OD011140), NHLBI, NIA, NIAID.
Gene Editing of Pigs to Control Influenza A Virus Infections
Kwon et al., Emerging Microbes & Infections. 2024.
https://pubmed.ncbi.nlm.nih.gov/39083026/
A reduction in the efficacy of vaccines and antiviral drugs for combating infectious diseases in agricultural animals has been observed. Generating genetically modified livestock species to minimize susceptibility to infectious diseases is of interest as an alternative approach. The researchers developed a homozygous transmembrane serine protease 2 (TMPRSS2) knockout (KO) porcine model to investigate resistance to two influenza A virus (IAV) subtypes, H1N1 and H3N2. TMPRSS2 KO pigs demonstrated diminished nasal cavity viral shedding, lower viral burden, and reduced microscopic lung pathology compared with wild-type (WT) pigs. In vitro culturing of primary bronchial epithelial cells (PBECs) demonstrated delayed viral replication in TMPRSS2 KO pigs compared with WT pigs. This study demonstrates the potential use of genetically modified pigs to mitigate IAV infections in pigs and limit transmission to humans. Supported by ORIP (U42OD011140), NHLBI, NIAID, and NIGMS.
Amphiphilic Shuttle Peptide Delivers Base Editor Ribonucleoprotein to Correct the CFTR R553X Mutation in Well-Differentiated Airway Epithelial Cells
Kulhankova et al., Nucleic Acids Research. 2024.
https://academic.oup.com/nar/article/52/19/11911/7771564?login=true
Effective translational delivery strategies for base editing applications in pulmonary diseases remain a challenge because of epithelial cells lining the intrapulmonary airways. The researchers demonstrated that the endosomal leakage domain (ELD) plays a crucial role in gene editing ribonucleoprotein (RNP) delivery activity. A novel shuttle peptide, S237, was created by flanking the ELD with poly glycine-serine stretches. Primary airway epithelia with the cystic fibrosis transmembrane conductance regulator (CFTR) R533X mutation demonstrated restored CFTR function when treated with S237-dependent ABE8e-Cas9-NG RNP. S237 outperformed the S10 shuttle peptide at Cas9 RNP delivery in vitro and in vivo using primary human bronchial epithelial cells and transgenic green fluorescent protein neonatal pigs. This study highlights the efficacy of S237 peptide–mediated RNP delivery and its potential as a therapeutic tool for the treatment of cystic fibrosis. Supported by ORIP (U42OD027090, U42OD026635), NCATS, NHGRI, NHLBI, NIAID, NIDDK, and NIGMS.
Cytomegalovirus Vaccine Vector-Induced Effector Memory CD4+ T cells Protect Cynomolgus Macaques From Lethal Aerosolized Heterologous Avian Influenza Challenge
Malouli et al., Nature Communications. 2024.
Development of a universal influenza vaccine that protects against seasonal strains and future pandemic influenza viruses is a necessity because of the limited efficacy of current influenza vaccines. Researchers developed a cynomolgus macaque β-herpesvirus cytomegalovirus (CyCMV) vaccine that targets the highly conserved proteins in influenza viruses. Male and female Mauritian-origin cynomolgus macaques (MCM) were vaccinated and boosted with the CyCMV vaccine prior to being challenged with small-particle aerosols containing highly pathogenic avian influenza (HPAI). MCMs receiving the CyCMV vaccine still presented with fever and pulmonary infiltration but demonstrated significant protection against HPAI-induced mortality. Unvaccinated MCMs challenged with HPAI did not survive. Survival was correlated with the magnitude of influenza-specific CD4+ T cells prior to infection. These results demonstrate the efficacy of a novel vaccine that protects against HPAI through a CD4 T cell–mediated response. Supported by ORIP (P51OD010425, P51OD011092) and NIAID.
Administration of Anti-HIV-1 Broadly Neutralizing Monoclonal Antibodies With Increased Affinity to Fcγ Receptors During Acute SHIV AD8-EO Infection
Dias et al., Nature Communications. 2024.
https://www.nature.com/articles/s41467-024-51848-y
Anti-HIV broadly neutralizing antibodies (bNAbs) mediate virus neutralization and antiviral effector functions through Fab and Fc domains, respectively. This study investigated the efficacy of wild-type (WT) bNAbs and modified bNAbs with enhanced affinity for Fcγ receptors (S239D/I332E/A330L [DEL]) after acute simian-HIVAD8-EO (SHIVAD8-EO) infection in male and female rhesus macaques. The emergence of the virus in the plasma and lymph nodes occurred earlier in macaques given DEL bNAbs than in those given WT bNAbs. Overall, the administration of DEL bNAbs revealed higher levels of immune responses. The results suggest that bNAbs with an enhanced Fcγ receptor affinity offer a potential therapeutic strategy by targeting HIV more effectively during early infection stages. Supported by ORIP (P40OD028116), NCI, and NIAID.