Selected Grantee Publications
CAR/CXCR5–T Cell Immunotherapy Is Safe and Potentially Efficacious in Promoting Sustained Remission of SIV Infection
Pampusch et al., PLOS Pathogens. 2022.
https://www.doi.org/10.1371/journal.ppat.1009831
HIV and simian immunodeficiency virus (SIV) replication are concentrated within the B cell follicles of secondary lymphoid tissues. In this study, the researchers developed immunotherapeutic chimeric antigen receptor (CAR) T cells that home to follicles and clear SIV-infected cells in a rhesus macaque model. The CAR T cells localized to the follicle, replicated, and interacted directly with infected cells. Most of the treated animals maintained lower viral loads in the blood and follicles, compared to control animals. These findings demonstrate the safety and potential efficacy of this immunotherapy approach for long-term remission of HIV without requiring the lifelong use of antiretroviral therapy. Supported by ORIP (P51OD011106), NIAID, and NHLBI.
Characterization of Near Full-Length Transmitted/Founder HIV-1 Subtype D and A/D Recombinant Genomes in a Heterosexual Ugandan Population (2006–2011)
Balinda et al., Viruses. 2022.
https://www.doi.org/10.3390/v14020334
About 80 percent of heterosexual HIV-1 transmission events are thought to be attributable to a single transmitted/founder (T/F) virus. Studies of HIV T/F viruses could yield valuable insights on transmission and help inform the design of vaccines and therapeutics. To date, most T/F studies have focused on subtype B and C viruses; few studies have focused on subtype D. In this study, the researchers characterized near full-length T/F viral genomes to identify subtype D and A/D recombinants from heterosexual mucosal transmissions in humans. They reported high viral diversity and high pathogenicity, underscoring the importance of matching vaccine designs to the predominant subtypes within populations. Further studies of the full genome sequence could provide additional information for subtyping. Supported by ORIP (P51OD011132) and NIAID.
Simian Immunodeficiency Virus Infection Mediated Changes in Jejunum and Peripheral SARS-CoV-2 Receptor ACE2 and Associated Proteins or Genes in Rhesus Macaques
Boby et al., Frontiers in Immunology. 2022.
https://www.doi.org/10.3389/fimmu.2022.835686
Recent studies suggest that people with HIV—particularly those not receiving antiretroviral therapy or those with low CD4 cell counts—are at increased risk of severe illness from SARS‑CoV-2 coinfection. Angiotensin-converting enzyme 2 (ACE2), the cellular receptor for SARS-CoV-2, is likely to play an important role in modulating physiological and pathological events during HIV infection. In this study, the researchers used a rhesus macaque model to characterize the expression profiles of ACE2, other renin-angiotensin system (RAS)–associated genes (AGTR1/2, ADAM17, and TMPRSS2), and inflammatory cytokines (IL-1β, IL-6, and TNF‑α) in the jejunum and lung during simian immunodeficiency virus (SIV) infection. SIV infection was associated with multiple changes in gene expression, including downregulation of ACE2, which could lead to loss of gut homeostasis. Further studies could provide insight on the role of RAS-associated proteins during HIV and SARS-CoV-2 co-infection. Supported by ORIP (P51OD011104) and NIDDK.
Functional and Ultrastructural Analysis of Reafferent Mechanosensation in Larval Zebrafish
Odstrcil et al., Current Biology. 2022.
https://www.sciencedirect.com/science/article/pii/S096098222101530X
All animals need to differentiate between exafferent stimuli (caused by the environment) and reafferent stimuli (caused by their own movement). Researchers characterized how hair cells in zebrafish larvae discriminate between reafferent and exafferent signals. Dye labeling of the lateral line nerve and functional imaging was combined with ultra-structural electron microscopy circuit reconstruction to show that cholinergic signals originating from the hindbrain transmit efference copies, and dopaminergic signals from the hypothalamus may affect threshold modulation. Findings suggest that this circuit is the core implementation of mechanosensory reafferent suppression in these young animals. Supported by ORIP (R43OD024879, R44OD024879) and NINDS.
Heritability of Social Behavioral Phenotypes and Preliminary Associations with Autism Spectrum Disorder Risk Genes in Rhesus Macaques: A Whole Exome Sequencing Study
Gunter et al., Autism Research. 2022.
https://onlinelibrary.wiley.com/doi/full/10.1002/aur.2675
Investigators quantified individual variation in social interactions among juvenile rhesus macaques of both sexes using both a standard macaque ethogram (a catalogue of animal behavior over time) and a macaque-relevant modification of the human Social Responsiveness Scale to study genetic influences on key aspects of social behavior and interactions. The analyses demonstrate that various aspects of juvenile social behavior exhibit significant genetic heritability, with quantitative genetic effects similar to autism spectrum disorder (ASD) in human children. The significant genetic and sequencing data may be used to examine potential genetic associations with human ASD. Supported by ORIP (P51OD011132), NHGRI and NIMH.
AAV5 Delivery of CRISPR-Cas9 Supports Effective Genome Editing in Mouse Lung Airway
Liang et al., Molecular Therapy. 2022.
https://www.cell.com/molecular-therapy-family/molecular-therapy/fulltext/S1525-0016(21)00530-X
Genome editing in the lung has the potential to provide long-term expression of therapeutic protein to treat lung genetic diseases. The authors illustrated that AAV5 can efficiently deliver CRISPR-Cas9 to mouse lung airways and was the first to achieve ∼20% editing efficiency in those airways. Results were confirmed through independent experiments at two different institutes. This highly efficient dual AAV platform will facilitate the study of genome editing in the lung and other tissue types. Supported by ORIP (U42OD026645).
Expression, Activity, and Regulation of Phosphorylating Enzymes in Tissues and Cells Relevant to HIV-1 Sexual Transmission
Hu et al., AIDS Research and Human Retroviruses. 2022.
https://www.doi.org/10.1089/AID.2020.0250
Phosphorylating enzymes (PEs) are critical for activating nucleoside/nucleotide reverse transcriptase inhibitors (e.g., tenofovir [TFV]), but limited information is available about the expression of PEs in the female genital tract and colon tissue. Investigators compared the mRNA expression of seven PEs involved in metabolism of TFV in cervicovaginal and colon tissues. This work involved human, pigtailed macaque, and rabbit tissues; human cervicovaginal epithelial cell lines; T cell lines; and primary CD4+ T cells. Taken together, this study suggests that TFV activation differs among immune cells and local tissues under varying conditions. Additionally, the variability of PE expression levels found across species provides critical information to assist with the interpretation of data obtained using these animal models. Supported by ORIP (P51OD010425) and NIAID.
Estimation of the In Vivo Neutralization Potency of eCD4Ig and Conditions for AAV-Mediated Production for SHIV Long-Term Remission
Goyal et al., Science Advances. 2022.
https://www.doi.org/10.1126/sciadv.abj5666
The engineered protein eCD4Ig, a synthetic antibody-like inhibitor designed to limit HIV entry into cells, shows promise as an approach to achieve HIV remission without antiretroviral therapy. Researchers used mathematical modeling to characterize in vivo antiviral neutralization of eCD4Ig, as well as possible antibody-dependent cell-mediated cytotoxicity effects, in rhesus macaques infected with simian–human immunodeficiency virus (SHIV) (sex not specified). The research team modeled SHIV and pharmacokinetics dynamics and projected the levels of eCD4Ig needed with a viral vector production approach to suppress SHIV viremia. The data suggest that endogenous, continuous expression of eCD4Ig could overcome the diminishing effects of antidrug antibodies and allow long-term remission of SHIV viremia in nonhuman primates. Supported by ORIP (P51OD011132) and NIAID.
Reduced Infant Rhesus Macaque Growth Rates Due to Environmental Enteric Dysfunction and Association with Histopathology in the Large Intestine
Hendrickson et al., Nature Communications. 2022.
https://www.doi.org/10.1038/s41467-021-27925-x
Researchers characterized environmental enteric (relating to the intestines) dysfunction (EED) among infant rhesus macaques (n=80, both sexes) naturally exposed to enteric pathogens commonly linked to human growth stunting. Despite atrophy and abnormalities observed in the small intestine, poor growth trajectories and low serum tryptophan (an amino acid needed for protein and enzymes) levels were correlated with increased histopathology (microscopic tissue examination for disease manifestation) in the large intestine. This study provides insight into the mechanisms underlying EED and indicates that the large intestine may be an important target for therapeutic intervention. Supported by ORIP (P51OD011092, P51OD011107) and NIGMS.
Neuroinflammatory Profiling in SIV-Infected Chinese-Origin Rhesus Macaques on Antiretroviral Therapy
Solis-Leal et al., Viruses. 2022.
https://www.doi.org/10.3390/v14010139
The central nervous system (CNS) HIV reservoir contributes to residual neuroimmune activation, which can lead to HIV-associated neurocognitive disorder. Researchers characterized the expression of signaling molecules associated with inflammation in plasma, cerebrospinal fluid, and basal ganglia of Chinese-origin rhesus macaques (sex not specified) with simian immunodeficiency virus (SIV). They reported a correlation between levels of CCL2 in plasma and cerebrospinal fluid, suggesting that researchers could infer the degree of CNS inflammation by testing CCL2 levels in peripheral blood. Overall, these findings provide insight into neuroinflammation and signaling associated with HIV persistence in the CNS. Supported by ORIP (P51OD011104, P51OD011133), NIMH, and NINDS.