Selected Grantee Publications
Previous Exposure to Dengue Virus Is Associated with Increased Zika Virus Burden at the Maternal-Fetal Interface in Rhesus Macaques
Crooks et al., PLOS Neglected Tropical Diseases. 2021.
https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0009641
Pre-existing immunity to dengue virus (DENV) results in antibody-dependent enhancement (ADE) among DENV serotypes; Zika virus (ZIKV) has homology with DENV suggesting pre-existing DENV immunity may have an impact on ZIKV pathogenesis during pregnancy. In a rhesus macaque model, prior DENV-2 exposure resulted in a higher burden of ZIKV viral RNA in maternal-fetal interface tissues as compared to DENV-naive macaques. However, pre-existing DENV immunity had no detectable impact on ZIKV replication kinetics in maternal plasma; all pregnancies progressed to term without adverse outcomes at delivery. Investigating potential ADE in pregnant women is important as vaccines against DENV and ZIKV are developed. Supported by ORIP (P51OD011106) and NIAID.
Factor XII Plays a Pathogenic Role in Organ Failure and Death in Baboons Challenged with Staphylococcus aureus
Silasi et al., Blood. 2021.
https://pubmed.ncbi.nlm.nih.gov/33598692/
Activation of coagulation factor (F) XI promotes multiorgan failure in rodent models of sepsis and in a baboon model for lethal systemic inflammation induced by infusion of heat-inactivated Staphylococcus aureus. The authors used the anticoagulant FXII-neutralizing antibody 5C12 to verify the mechanistic role of FXII. Inhibition of FXII prevented fever, terminal hypotension, respiratory distress, and multiorgan failure. All animals receiving 5C12 had milder and transient clinical symptoms; untreated control animals suffered irreversible multiorgan failure. This study confirms their previous finding that at least two enzymes of FXIa and FXIIa play critical roles in the development of an acute and terminal inflammatory response. Supported by ORIP (P40OD024628), NIAID, NHLBI, and NIGMS.
A Yeast Expressed RBD-Based SARS-CoV-2 Vaccine Formulated with 3M-052-alum Adjuvant Promotes Protective Efficacy in Non-Human Primates
Pino et al., Science Immunology. 2021.
https://immunology.sciencemag.org/content/6/61/eabh3634
Using a rhesus macaque model (n=5 males per group), investigators tested a receptor binding domain (RBD) recombinant protein formulation COVID-19 vaccine candidate combined with an aluminum-based formulation of 3M’s Toll-like receptor 7 and 8 agonist 3M-052 (3M-052/Alum) and found the RBD+3M-052/Alum formulation produced a superior overall immune response than RBD+alum alone as demonstrated by higher SARS-CoV-2 neutralizing antibodies, improved Th1 biased CD4+ T cell reactions, and increased CD8+ T cell responses. Collectively, these data suggest that the RBD+3M-052-alum formulation provides robust immune responses against SARS-CoV-2 and supports the development of this potential effective and easy to scale COVID-19 vaccine candidate. Supported by ORIP (P51OD011132) and NIAID.
Systems Vaccinology of the BNT162b2 mRNA Vaccine in Humans
Arunachalam et al., Nature . 2021.
https://doi.org/10.1038/s41586-021-03791-x
It was poorly understood how mRNA vaccines against SARS-CoV-2 stimulate protective immune responses. To address this, researchers comprehensively profiled innate and adaptive immune responses of healthy volunteers vaccinated with the Pfizer-BioNTech mRNA vaccine (BNT162b2). Vaccination resulted in robust production of neutralizing antibodies against wild-type SARS-CoV-2, to a lesser extent, the beta variant, as well as significant increases in antigen-specific polyfunctional CD4+ and CD8+ T cells after the second dose. Booster vaccination stimulated an enhanced innate immune response compared to primary vaccination, demonstrating the capacity of BNT162b2 to prime the innate immune system to mount a more potent response after booster immunization. Supported by ORIP (P51OD011132, S10OD026799) and NIAID.
Early Treatment With a Combination of Two Potent Neutralizing Antibodies Improves Clinical Outcomes and Reduces Virus Replication and Lung Inflammation in SARS CoV-2 Infected Macaques
Van Rompay et al., PLOS Pathogens. 2021.
https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1009688
The therapeutic efficacy of a combination of two SARS-CoV-2 monoclonal antibodies (mAbs), C135-LS and C144-LS, were investigated in young adult macaques (3 groups of 4 animals; equal sex distribution). Animals were treated intravenously with low or high doses of C135-LS and C144-LS mAbs or control mAb 24 hours post-infection with SARS-CoV-2. Compared to controls, animals treated with either dose of the anti-SARS-CoV-2 mAbs showed improved clinical scores, lower levels of virus replication in upper and lower respiratory tract, and reduced interstitial pneumonia, as measured by lung histology. The study provides proof-of-concept for development of these mAbs for treatment of COVID-19 during early infection. Supported by ORIP (P51OD011107) and NIAID.
Interleukin-15 Response Signature Predicts RhCMV/SIV Vaccine Efficacy
Barrenäs et al., PLOS Pathogens. 2021.
https://doi.org/10.1371/journal.ppat.1009278
Standard immunogenicity measures do not predict efficacy of a vaccine based on strain 68-1 rhesus cytomegalovirus (RhCMV) vectors expressing SIV proteins (RhCMV/SIV). This vaccine robustly protects just over half of immunized monkeys. Using functional genomics, researchers found that RhCMV/SIV efficacy is correlated with a vaccine-induced response to interleukin-15 (IL-15) that includes modulation of immune cell, inflammation, toll-like receptor signaling, and cell death programming pathways. RhCMV/SIV imparts a coordinated and persistent induction of innate and adaptive immune pathways featuring IL-15, a known regulator of CD8+ T cell function, that support the ability of vaccine-elicited CD8+ T cells to mediate protection against SIV. Supported by ORIP (P51OD010425, P51OD011092), NIAID, and NCI.
Recrudescence of Natural Coccidioidomycosis During Combination Antiretroviral Therapy in a Pigtail Macaque Experimentally Infected with Simian Immunodeficiency Virus
Guerriero et al., AIDS Research and Human Retroviruses. 2021.
https://doi.org/10.1089/AID.2020.0228
Coccidioidomycosis is a common fungal infection in people living with HIV, particularly in regions where Coccidioides is endemic, such as the U.S. Southwest. Researchers diagnosed a recrudescent case of previously treated, naturally occurring coccidioidomycosis in a pigtail macaque experimentally infected with simian immunodeficiency virus (SIV) and virally suppressed on combination antiretroviral therapy (cART). Coccidioides IgG antibody titer became detectable before discontinuation of cART, but symptomatic coccidioidomycosis developed after cART withdrawal. This animal was screened and treated in accordance with the guidelines for coccidioidomycosis prevention and treatment. The researchers conclude that macaques with coccidioidomycosis history should be excluded from HIV studies. Supported by ORIP (P51OD010425), NIAID, and NIMH.
Protection of Newborn Macaques by Plant-Derived HIV Broadly Neutralizing Antibodies: A Model for Passive Immunotherapy During Breastfeeding
Rosenberg et al., Journal of Virology. 2021.
https://doi.org/10.1128/JVI.00268-21
Preventing vertical transmission of HIV to newborns is an unmet medical need in resource poor countries. Using a breastfeeding macaque model with multiple simian-human immunodeficiency virus challenge, researchers assessed the protective efficacy of two human broadly neutralizing antibodies (bnAbs) against HIV, PGT121 and VRC07-523, which are produced by a plant expression system. Despite the transient presence of plasma viral RNA, the bnAbs prevented productive infection in all newborns with no sustained plasma viremia, compared to viral loads ranging from 103 to 5x108 in four untreated controls. Thus, plant-expressed antibodies show promise as passive immunoprophylaxis in a breastfeeding model in newborns. Supported by ORIP (U42OD023038, P51OD011092) and NIAID.
Tissue-Specific Transcriptional Profiling of Plasmacytoid Dendritic Cells Reveals a Hyperactivated State in Chronic SIV Infection
Lee et al., PLOS Pathogens. 2021.
https://doi.org/10.1371/journal.ppat.1009674
Persistent immune activation is an obstacle to optimal health for people living with HIV. Using RNA sequencing, researchers investigated the immunostimulatory potential of plasmacytoid dendritic cells (pDCs) in chronic SIV infection in rhesus macaques. They observed that pDCs have highly activated profiles in these animals. In contrast, pDCs from SIV-infected sooty mangabeys (natural hosts for SIV) had expression profiles similar to uninfected animals. In chronically infected rhesus macaques, interferon alpha transcripts were readily detected in lymph node-homing pDCs, but not those from blood. Therefore, pDCs are a major producer of type-I interferon in chronic SIV infection and could be a useful immunotherapy target. Supported by ORIP (R24OD010445, P51OD011132, P51OD011092, S10OD026799) and NIAID.
Immune Inactivation of Anti-Simian Immunodeficiency Virus Chimeric Antigen Receptor T Cells in Rhesus Macaques
Haeseleer et al., Molecular Therapy–Methods & Clinical Development. 2021.
https://doi.org/10.1016/j.omtm.2021.06.008
Chimeric antigen receptor (CAR) T cell therapies are under development as potential HIV cures. Researchers found that CAR T cells expressing a single-chain variable fragment (scFv) that recognizes V1 or V3 of the SIV envelope eliminated SIV-infected T cells in vitro. However, in vivo infusion of these CAR T cells in rhesus macaques resulted in no detectable antiviral activity. Anti-SIV IgG antibodies in the SIV-infected animals were associated with inhibited CAR T cell effector functions. Thus, lack of in vivo efficacy of CAR T cells might be due to antibodies blocking the interaction between the CAR scFv and its epitope. Supported by ORIP (P51OD011092) and NIAID.