Selected Grantee Publications
Neuroinflammatory Transcriptional Programs Induced in Rhesus Pre‑Frontal Cortex White Matter During Acute SHIV Infection
Hawes et al., Journal of Neuroinflammation. 2022.
https://www.doi.org/10.1186/s12974-022-02610-y
Neuroinflammation has evolved as a protective immune response within the central nervous system (CNS), but chronic neuroinflammation leads to oxidative stress, cellular damage, and neurodegeneration. People living with HIV are at increased risk for age-related neurodegenerative diseases. Using rhesus macaques of both sexes, the researchers characterized the molecular underpinnings of acute neuroinflammation following simian–human immunodeficiency virus (SHIV) infection. Viral entry and integration within the CNS demonstrated vulnerabilities of key cognitive and motor function brain regions during the acute phase of infection. SHIV-induced transcriptional alterations also were observed. These findings indicate the presence of pervasive immune surveillance at homeostasis and reveal key perturbations during infection. Supported by ORIP (S10OD010786, K01OD023034) and NIAID.
Distinct Sensitivities to SARS-CoV-2 Variants in Vaccinated Humans and Mice
Walls et al., Cell Reports. 2022.
https://www.doi.org/10.1016/j.celrep.2022.111299
Emergence of SARS-CoV-2 variants necessitates real-time evaluation of their impact on serum neutralizing activity, as a proxy for vaccine efficacy, to inform public health policies and guide vaccine development. The investigators report that vaccinated female BALB/c mice do not recapitulate faithfully the breadth and potency of neutralizing antibody responses toward the SARS-CoV-2 Beta and Gamma variants of concern, compared with humans of both sexes and male nonhuman primates (i.e., rhesus and pigtail macaques). This finding was consistent across several vaccine modalities, doses, antigens, and assays, suggesting caution should be exercised when interpreting serum neutralizing data obtained from mice. Supported by ORIP (P51OD010425, U42OD011123) and NIAID.
Molecular Insights Into Antibody-Mediated Protection Against the Prototypic Simian Immunodeficiency Virus
Zhao et al., Nature Communications. 2022.
https://www.doi.org/10.1038/s41467-022-32783-2
Most simian immunodeficiency virus (SIV) vaccines have focused on inducing T cell responses alone or in combination with non-neutralizing antibody responses. To date, studies investigating neutralizing antibody (nAb) responses to protect against SIV have been limited. In this study, researchers isolated 12 potent monoclonal nAbs from chronically infected rhesus macaques of both sexes and mapped their binding specificities on the envelope trimer structure. They further characterized the structures using cryogenic electron microscopy, mass spectrometry, and computational modeling. Their findings indicate that, in the case of humoral immunity, nAb activity is necessary and sufficient for protection against SIV challenge. This work provides structural insights for future vaccine design. Supported by ORIP (P51OD011106), NIAID, and NCI.
Profiling Development of Abdominal Organs in the Pig
Gabriel et al., Scientific Reports. 2022.
https://www.doi.org/10.1038/s41598-022-19960-5
The pig is a model system for studying human development and disease due to its similarities to human anatomy, physiology, size, and genome. Moreover, advances in CRISPR gene editing have made genetically engineered pigs a viable model for the study of human pathologies and congenital anomalies. However, a detailed atlas illustrating pig development is necessary for identifying and modeling developmental defects. Here, the authors describe normal development of the pig abdominal system (i.e., kidney, liver, pancreas, spleen, adrenal glands, bowel, gonads) and compare them with congenital defects that can arise in gene-edited SAP130 mutant pigs. This atlas and the methods described here can be used as tools for identifying developmental pathologies of the abdominal organs in the pig at different stages of development. Supported by ORIP (U42OD011140), NHLBI, NIAID, NIBIB, NICHD, and NINDS.
Wastewater Sequencing Reveals Early Cryptic SARS-CoV-2 Variant Transmission
Karthikeyan et al., Nature. 2022.
https://www.doi.org/10.1038/s41586-022-05049-6
The investigators explored the use of SARS-CoV-2 RNA concentration in wastewater as a practical approach to estimate community prevalence of COVID-19, detect emerging variants, and track regional infection dynamics. Two obstacles must be overcome to leverage wastewater-based genomic surveillance: low-quality sequence data and inability to estimate relative lineage abundance in mixed samples. The investigators developed and deployed improved virus concentration protocols and deconvolution software to fully resolve multiple virus strains from wastewater. Results indicate that emerging variants of concern were detected up to 14 days earlier in wastewater samples, and multiple instances of virus spread that were not captured by clinical genomic surveillance were identified by wastewater-based genomic surveillance. The study provides a scalable solution for wastewater genomic surveillance that allows early detection of SARS-CoV-2 variants and identification of cryptic transmission. The work suggests a critical, urgently needed methodology for early detection of emerging variants and early public health interventions. Supported by ORIP (S10OD026929), and NIAID.
Early Treatment Regimens Achieve Sustained Virologic Remission in Infant Macaques Infected with SIV at Birth
Wang et al., Nature Communications. 2022.
https://www.doi.org/10.1038/s41467-022-32554-z
About 150,000 children are infected postnatally with HIV each year. Early antiretroviral therapy (ART) in infants with HIV can reduce viral reservoir size, but ART-free virologic remission has not been achieved. The researchers hypothesized that proviral reservoir seeding in infants exposed to HIV might differ from that in adults. They characterized viral reservoirs in neonatal rhesus macaques of both sexes inoculated with simian immunodeficiency virus (SIV) at birth and given combination ART. The researchers reported that 9 months of treatment initiated at day 3 resulted in a sustained virologic remission, suggesting that early intervention with proper treatment regimens could be an effective strategy. Supported by ORIP (P51OD011104), NIAID, NICHD, and NIDCR.
Parallel Processing, Hierarchical Transformations, and Sensorimotor Associations along the “Where” Pathway
Doudlah et al., eLife. 2022.
https://www.doi.org/10.7554/eLife.78712
Visually guided behaviors require the brain to transform ambiguous retinal images into object-level spatial representations and map those representations to motor responses. These capabilities are supported by the dorsal “where” pathway in the brain, but the specific contributions of areas along this pathway have remained elusive. Using a rhesus macaque model, researchers compared neuronal activity in two areas along the “where” pathway that bridge the parieto-occipital junction: intermediate visual area V3A and the caudal intraparietal (CIP) area. Neuronal activity was recorded while the animals made perceptual decisions based on judging the tilt of 3D visual patterns. The investigators found that CIP shows higher-order spatial representations and more choice-correlated responses, which support a V3A-to-CIP hierarchy. The researchers also discovered modulation of V3A activity by extraretinal factors, suggesting that V3A might be better characterized as contributing to higher-order behavioral functions rather than low-level visual feature processing. Supported by ORIP (P51OD011106), NEI, NICHD, and NINDS.
Durable Protection Against the SARS-CoV-2 Omicron Variant Is Induced by an Adjuvanted Subunit Vaccine
Arunachalam et al., Science Translational Medicine. 2022.
https://www.doi.org/10.1126/scitranslmed.abq4130
Additional SARS-CoV-2 vaccines are needed, owing to waning immunity to the original vaccines and the emergence of variants of concern. A recent study in male rhesus macaques demonstrated durable protection against the Omicron BA.1 variant induced by a subunit SARS-CoV-2 vaccine comprising the receptor binding domain of the ancestral strain (RBD-Wu) on the I53-50 nanoparticle adjuvanted with AS03, an oil-in-water emulsion containing α‑tocopherol. Two immunizations with the vaccine resulted in durable immunity, without cross-reactivity. Further boosting with a version of the vaccine containing the Beta variant or the ancestral RBD elicited cross-reactive immune responses that conferred protection against Omicron challenge. Supported by ORIP (P51OD011104), NCI, and NIAID.
Mosaic RBD Nanoparticles Protect Against Challenge by Diverse Sarbecoviruses in Animal Models
Cohen et al., Science. 2022.
https://www.doi.org/10.1126/science.abq0839
Two animal coronaviruses from the SARS-like betacoronavirus (sarbecovirus) lineage—SARS-CoV and SARS-CoV-2—have caused epidemics or pandemics in humans during the past 20 years. New SARS-CoV-2 variants have prolonged the COVID-19 pandemic, and the discovery of diverse sarbecoviruses in bats raises the possibility of another coronavirus pandemic. Vaccines and therapeutics are needed to protect against both SARS-CoV-2 variants and zoonotic sarbecoviruses with the potential to infect humans. The authors designed mosaic-8 nanoparticles (SARS-CoV-2 and seven animal sarbecoviruses) that present randomly arranged sarbecovirus spike receptor-binding domains (RBDs) to elicit antibodies against epitopes that are conserved and relatively occluded rather than variable, immunodominant, and exposed. Their results of immune responses elicited by mosaic-8 RBD nanoparticles in mice and macaques suggest that mosaic nanoparticles could protect against both SARS-CoV-2 variants and zoonotic sarbecoviruses with the potential to infect humans. Supported by ORIP (P40OD012217, U42OD021458, S10OD028685) and NIAID.
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.