Selected Grantee Publications
Recreating the Heart’s Helical Structure–Function Relationship With Focused Rotary Jet Spinning
Chang et al., Science. 2022.
https://www.doi.org/10.1126/science.abl6395
The investigators developed a tissue engineering approach that enables rapid deposition of cardiomyocyte microfibers with programmable alignments in 3D geometries. Using this focused rotary jet spinning (FRJS) method, they reproduced tissue scaffolds with contractile cells' helical alignments, resembling complex structures of the musculature and properties of a natural heart. This work represents an important advance towards biofabrication of tissue models for healthy and diseased hearts by manipulating orientation of specific fibers. With the technological advancement over other competing methods, FRJS might provide a pathway towards fabricating other tissues and organs with diverse cell populations. Supported by ORIP (S10OD023519) and NCATS.
Infection Order Outweighs the Role of CD4+ T Cells in Tertiary Flavivirus Exposure
Marzan-Rivera et al., iScience. 2022.
https://www.doi.org/10.1016/j.isci.2022.104764
The link between CD4+ T and B cells in immune responses to Dengue virus (DENV) and Zika virus (ZIKV) and their roles in cross-protection during heterologous infection are poorly known. The authors used CD4+ lymphocyte depletions to dissect the impact of cellular immunity on humoral responses during tertiary flavivirus infection in male macaques. CD4+ depletion in DENV/ZIKV–primed animals, followed by DENV, resulted in dysregulated adaptive immune responses. They show a delay in DENV-specific antibody titers and binding and neutralization in the DENV/ZIKV–primed, CD4-depleted animals but not in ZIKV/DENV–primed, CD4-depleted animals. This study confirms the role of CD4+ cells in priming an early humoral response during sequential flavivirus infections and suggests that the order of exposure affects the outcome of a tertiary infection. Supported by ORIP (P40OD012217), NIAID, and NIGMS.
A Clade C HIV-1 Vaccine Protects Against Heterologous SHIV Infection by Modulating IgG Glycosylation and T Helper Response in Macaques
Sahoo et al., Science Immunology. 2022.
https://www.doi.org/10.1126/sciimmunol.abl4102
Vaccines for HIV-1 capable of generating a broadly cross-reactive neutralizing antibody response are needed urgently. The researchers tested the protective efficacy of a clade C HIV-1 vaccination regimen in male rhesus macaques. The vaccine was administered either orally using a needle-free injector or via parenteral injection. Significant protection was observed for both vaccination routes following the simian–human immunodeficiency virus (SHIV) challenge, with an estimated efficacy of 68% per exposure. The glycosylation profile of IgG and HIV-resistant helper T cell response contributes to the protection. Supported by ORIP (P51OD011132), NIAID, and NIDCR.
Innate Immune Regulation in HIV Latency Models
Olson et al., Retrovirology. 2022.
https://www.doi.org/10.1186/s12977-022-00599-z
Researchers are interested in developing therapeutic approaches to target latent HIV reservoirs, which are unaffected by antiretroviral therapy. Previous studies suggest that HIV latency might be related to viral RNA sensing, interferon (IFN) signaling, and IFN-stimulated gene (ISG) activation. In this study, the researchers evaluated responses to stimulation by retinoic acid–inducible gene I agonists and IFN in multiple CD4+ T cell line models for HIV latency. The models represented various aspects of latent infection and viral control. Several of the cell lines demonstrated reduced ISG induction, suggesting that long-term latency might be related to dysregulation of the downstream IFN response. These effects likely reflect transcriptional changes occurring within a core set of ISGs and altering IFN responses. Additional studies could provide insight into the functions of these ISGs in HIV latency. Supported by ORIP (P51OD010425), NCATS, and NIAID.
Safety and Antiviral Activity of Triple Combination Broadly Neutralizing Monoclonal Antibody Therapy Against HIV-1: A Phase 1 Clinical Trial
Julg et al., Nature Medicine. 2022.
https://www.doi.org/10.1038/s41591-022-01815-1
Previous evidence suggests that at least three broadly neutralizing antibodies (bNAbs) targeting different epitope regions are needed for robust treatment and control of HIV. The investigators evaluated the safety, tolerability, and pharmacokinetics of PGDM1400, an HIV-1 V2-glycan–specific antibody, in a first-in-human trial. The primary endpoints were safety, tolerability, pharmacokinetics, and antiviral activity. The trial met the prespecified endpoints in male and female adults. These data will help advance understanding of the capabilities, limitations, and future role of bNAb combinations in HIV prevention and care. Supported by ORIP (R01OD024917), NIAID, and NCATS.
Substitutions in Nef That Uncouple Tetherin and SERINC5 Antagonism Impair Simian Immunodeficiency Virus Replication in Primary Rhesus Macaque Lymphocytes
Janaka et al., Journal of Virology. 2022.
https://www.doi.org/10.1128/jvi.00176-22
Tetherin inhibits the release of certain enveloped viruses from infected host cells. Most simian immunodeficiency viruses (SIVs) use Nef, a nonenzymatic accessory protein, to overcome this restriction. Nef also has been shown to enhance viral infectivity by preventing the incorporation of SERINC5 into virions. Researchers demonstrated previously that tetherin antagonism is necessary for efficient SIV replication in rhesus macaques. They explored this effect by defining substitutions within Nef that distinguish tetherin and SERINC5 antagonism. The researchers engineered an SIV molecular clone with substitutions that uncouple relevant Nef functions. This clone can be used to further study the effects of tetherin and adaptive immune responses. Supported by ORIP (P51OD011106) and NIAID.
Myeloid Cell Tropism Enables MHC-E–Restricted CD8+ T Cell Priming and Vaccine Efficacy by the RhCMV/SIV Vaccine
Hansen et al., Science Immunology. 2022.
https://www.doi.org/10.1126/sciimmunol.abn9301
Simian immunodeficiency virus (SIV) vaccines based on strain 68-1 rhesus cytomegalovirus vectors have been shown to arrest viral replication early in primary infection. The specific characteristics underlying this effect are not understood fully. In this study, the researchers used host microRNA–mediated vector tropism restriction to demonstrate that the targeted responses are dependent on vector infection of distinct cell types in a rhesus macaque model. Only vectors programmed to elicit major histocompatibility complex E–restricted CD8+ T cell responses provided protection against SIV challenge. These findings could be applied in the development of other vaccines for cancers and infectious diseases. Supported by ORIP (P51OD011092), NCI, and NIAID.
A Cellular Trafficking Signal in the SIV Envelope Protein Cytoplasmic Domain Is Strongly Selected for in Pathogenic Infection
Lawrence et al., PLOS Pathogens. 2022.
https://www.doi.org/10.1371/journal.ppat.1010507
Envelope glycoproteins within the cytoplasmic domain of HIV and simian immunodeficiency virus (SIV) include a tyrosine-based motif that mediates endocytosis and polarized sorting in infected cells. Mutation of this tracking signal has been shown to lead to suppressed viral replication and failed systemic immune activation, but the mechanism has not been explored fully. Using rhesus and pigtail macaque models, the researchers demonstrated that molecular clones containing the mutations reconstitute signals for both endocytosis and polarized sorting. Their findings suggest strong selection pressure for these processes during pathogenic HIV and SIV infection. Supported by ORIP (P51OD011104), NCI, and NIAID.
Large Comparative Analyses of Primate Body Site Microbiomes Indicate That the Oral Microbiome Is Unique Among All Body Sites and Conserved Among Nonhuman Primates
Asangba et al., Microbiology Spectrum. 2022.
https://www.doi.org/10.1128/spectrum.01643-21
Microbiomes are critical to host health and disease, but large gaps remain in the understanding of the determinants, coevolution, and variation of microbiomes across body sites and host species. Thus, researchers conducted the largest comparative study of primate microbiomes to date by investigating microbiome community composition at eight distinct body sites in 17 host species. They found that the oral microbiome is unique in exhibiting notable similarity across primate species while being distinct from the microbiomes of all other body sites and host species. This finding suggests conserved oral microbial niche specialization, despite substantial dietary and phylogenetic differences among primates. Supported by ORIP (P51OD010425, P51OD011107, P40OD010965, R01OD010980), NIA, NIAID, and NICHD.
The Ex Vivo Pharmacology of HIV-1 Antiretrovirals Differs Between Macaques and Humans
Herrera et al., iScience. 2022.
https://www.doi.org/10.1016/j.isci.2022.104409
Nonhuman primates (NHPs) are used widely for studies of antiretroviral (ARV)–based pre‑exposure prophylaxis (PrEP), but more work is needed to address dose–efficacy discrepancies between NHP studies and human clinical trials of PrEP candidates. Investigators explored the use of colorectal and cervicovaginal ex vivo mucosal tissue explants as a bridging model between NHPs and humans. They reported differences in inhibitory potency of drug combinations between NHP and human mucosal tissue explants. These findings suggest that tissue explants can help researchers refine and interpret NHP ARV studies. Supported by ORIP (P51OD011104) and NIAID.