Selected Grantee Publications
Large Animal Models Enhance the Study of Crypt-Mediated Epithelial Recovery From Prolonged Intestinal Ischemia Reperfusion Injury
McKinney-Aguirre et al., American Journal of Physiology-Gastrointestinal and Liver Physiology. 2024.
https://pubmed.ncbi.nlm.nih.gov/39404771/
Intestinal ischemia and reperfusion injury (IRI) is a severe pathological alteration that compromises the intestinal epithelial barrier, causing bacterial translocation, shock, sepsis, and potentially death. Preclinical research for IRI has focused on utilizing murine models, but mice demonstrate key anatomical and physiological intestinal differences from humans, such as tissue enzymes, intestinal permeability, and hypoxic response pathways. The researchers compared a 3-hour IRI porcine model to a 3-hour IRI murine model to reveal which demonstrated a stronger translational capacity. Both models demonstrated crypt damage, but only the porcine model showed recovery-associated crypt death expansion and re-epithelialization. At 72 hours post-IRI, mouse mortality was 84.6%, whereas porcine mortality was 0%. A porcine model would be more reliable for future translational studies focused on understanding IRI mechanisms for diagnosis and therapy advancements. Supported by ORIP (T32OD011130, K01OD010199, R03OD026598) and NIDDK.
Enterohemorrhagic Escherichia coli (EHEC) Disrupts Intestinal Barrier Integrity in Translational Canine Stem Cell-Derived Monolayers
Nagao et al., Microbiology Spectrum. 2024.
https://pubmed.ncbi.nlm.nih.gov/39162490/
EHEC produces Shiga toxin, which causes acute colitis with symptoms such as hemolytic uremic syndrome and bloody diarrhea. The researchers developed a colonoid-derived monolayer model to understand EHEC’s impact on canine gut health. Colonoid-derived monolayers co-cultured with EHEC demonstrated key differences compared with the control and nonpathogenic E. coli co-cultures. Scanning electron microscopy displayed EHEC aggregated and attached to the microvilli. EHEC-infected monolayers demonstrated significantly weakened membrane integrity and increased inflammatory cytokine production, specifically TNFα. The researchers developed a novel in vitro model that offers an additional platform for understanding the mechanisms of EHEC pathogenicity, developing therapeutics for EHEC, and studying additional enteric pathogens. Supported by ORIP (K01OD030515, R21OD031903).
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.
Human Stem Cell-Derived Cardiomyocytes Integrate Into the Heart of Monkeys With Right Ventricular Pressure Overload
Scholz et al., Cell Transplantation. 2024.
https://journals.sagepub.com/doi/10.1177/09636897241290367
Patients with single-ventricle congenital heart defects suffer from right ventricular pressure overload (RVPO). Researchers developed a novel pulmonary artery banding (PAB) rhesus macaque model to induce RVPO. This study investigated the efficacy of human induced pluripotent stem cell cardiac lineage cell (hiPSC-CL) delivery at low or high dose into adult male and female rhesus macaques with right ventricular dysfunction. The findings indicate that hiPSC-CLs were successfully grafted and integrated to match the surrounding host right ventricle myocardium. These results suggest hiPSC-CL therapy is a potential adjunctive treatment for RVPO, but future research will be needed to elucidate the beneficial effects. Supported by ORIP (P51OD011106).
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.
Comparison of the Immunogenicity of mRNA-Encoded and Protein HIV-1 Env-ferritin Nanoparticle Designs
Mu et al., Journal of Virology. 2024.
https://journals.asm.org/doi/10.1128/jvi.00137-24
Inducing broadly neutralizing antibodies (bNAbs) against HIV-1 remains a challenge because of immune system limitations. This study compared the immunogenicity of mRNA-encoded membrane-bound envelope (Env) gp160 to HIV-1 Env-ferritin nanoparticle (NP) technology in inducing anti-HIV-1 bNAbs. Membrane-bound mRNA encoding gp160 was more immunogenic than the Env-ferritin NP design in DH270 UCA KI mice, but at lower doses. These results suggest further analysis of mRNA design expression and low-dose immunogenicity studies are necessary for anti-HIV-1 bNAbs. Supported by ORIP (P40OD012217, U42OD021458) and NIAID.
Commentary: The International Mouse Phenotyping Consortium: High-Throughput In Vivo Functional Annotation of the Mammalian Genome
Lloyd, Mammalian Genome. 2024.
https://pubmed.ncbi.nlm.nih.gov/39254744
The International Mouse Phenotyping Consortium (IMPC), a collectively governed consortium of 21 academic research institutions across 15 countries on 5 continents, represents a groundbreaking approach in genetics and biomedical research. Its goal is to create a comprehensive catalog of mammalian gene function that is freely available and equally accessible to the global research community. So far, the IMPC has uncovered the function of thousands of genes about which little was previously known. By 2027, when the current round of funding expires, the IMPC will have produced and phenotyped nearly 12,000 knockout mouse lines representing approximately 60% of the human orthologous genome in mice. This new knowledge has produced numerous insights about the role of genes in health and disease, including informing the genetic basis of rare diseases and positing gene product influences on common diseases. However, as IMPC nears the end of the current funding cycle, its path forward remains unclear. Supported by ORIP (UM1OD023221).
A New Atlas to Study Embryonic Cell Types in Xenopus
Petrova et al., Developmental Biology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38614285
Petrova et al. have designed a new single-cell atlas for developmental stages in Xenopus tropicalis that encompasses gastrulation, neurulation, and early tail bud. Compared to its predecessors, the new atlas enhances gene mapping, read counts, and gene/cell-type nomenclature. The atlas also leverages the latest X. tropicalis genome version to maintain consistency with previous cell-type annotations while rectifying prior nomenclature issues. The new resource emphasizes previously unexplored germ-cell populations in which novel transcription onset features have been uncovered. Finally, the new atlas offers interactive exploration through a user-friendly web portal and allows users to download complete data sets. Supported by ORIP (R24OD031956).
Spatiotemporal Image Reconstruction to Enable High-Frame-Rate Dynamic Photoacoustic Tomography With Rotating-Gantry Volumetric Imagers
Cam et al., Journal of Biomedical Optics . 2024.
https://pubmed.ncbi.nlm.nih.gov/38249994
Dynamic photoacoustic computed tomography (PACT) is a valuable imaging technique for monitoring physiological processes. However, the current imaging techniques are often limited to two-dimensional spatial imaging. While PACT imagers capable of taking three-dimensional spatial images are commercially available, these systems have substantial limitations. Typically, the data are acquired sequentially rather than simultaneously at all views. The objects being imaged are dynamic and can vary during this process; as such, image reconstruction is inherently difficult, and the result is often incomplete. Cam et al. propose an image reconstruction method that can address these challenges and enable volumetric dynamic PACT imaging using existing preclinical imagers, which has the potential to significantly advance preclinical research and facilitate the monitoring of critical physiological biomarkers. Supported by ORIP (R44OD023029) and NIBIB.