Selected Grantee Publications
Genetic Basis For an Evolutionary Shift From Ancestral Preaxial to Postaxial Limb Polarity in Non-urodele Vertebrates
Trofka et al., Current Biology. 2021.
https://www.sciencedirect.com/science/article/pii/S0960982221012501
In most tetrapod vertebrates, limb skeletal progenitors condense with postaxial dominance. Posterior elements (ulna and fibula) appear prior to their anterior counterparts (radius and tibia), followed by digit-appearance order with continuing postaxial polarity. Recent fossil evidence suggests that preaxial polarity represents an ancestral rather than derived state. These authors report that 5'Hoxd (Hoxd11-d13) gene deletion in mouse is atavistic and uncovers an underlying preaxial polarity in mammalian limb formation. Evolutionary changes in Gli3R activity level, key in the fin-to-limb transition, appear to be fundamental to the shift from preaxial to postaxial polarity in formation of the tetrapod limb skeleton. Supported by ORIP (P40OD01979) and NCI.
Multiplexed Drug-Based Selection and Counterselection Genetic Manipulations in Drosophila
Matinyan et al., Cell Reports. 2021.
https://www.cell.com/cell-reports/pdf/S2211-1247(21)01147-5.pdf
Many highly efficient methods exist which enable transgenic flies to contribute to diagnostics and therapeutics for human diseases. In this study, researchers describe a drug-based genetic platform with four selection and two counterselection markers, increasing transgenic efficiency by more than 10-fold compared to established methods in flies. Researchers also developed a plasmid library to adapt this technology to other model organisms. This highly efficient transgenic approach significantly increases the power of not only Drosophila melanogaster but many other model organisms for biomedical research. Supported by ORIP (P40OD018537, P40OD010949, R21OD022981), NCI, NHGRI, NIGMS, and NIMH.
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.
Innate Immunity Stimulation via CpG Oligodeoxynucleotides Ameliorates Alzheimer’s Disease Pathology in Aged Squirrel Monkeys
Patel et al., Brain: A Journal of Neurology. 2021.
https://pubmed.ncbi.nlm.nih.gov/34128045/
Alzheimer's disease is the only illness among the top 10 causes of death for which there is no disease-modifying therapy. The authors have shown in transgenic Alzheimer's disease mouse models that harnessing innate immunity via TLR9 agonist CpG oligodeoxynucleotides (ODNs) modulates age-related defects associated with immune cells and safely reduces amyloid plaques, oligomeric amyloid-β, tau pathology, and cerebral amyloid angiopathy (CAA). They used a nonhuman primate model for sporadic Alzheimer's disease pathology that develops extensive CAA-elderly squirrel monkeys. They demonstrate that long-term use of Class B CpG ODN 2006 induces a favorable degree of innate immunity stimulation. CpG ODN 2006 has been well established in numerous human trials for a variety of diseases. This evidence together with their earlier research validates the beneficial therapeutic outcomes and safety of this innovative immunomodulatory approach. Supported by ORIP (P40OD010938), NINDS, NIA, and NCI.
IL-21 and IFNα Therapy Rescues Terminally Differentiated NK Cells and Limits SIV Reservoir in ART-Treated Macaques
Harper et al., Nature Communications. 2021.
https://doi.org/10.1038/s41467-021-23189-7
Nonpathogenic simian immunodeficiency virus (SIV) infections in natural hosts, such as vervet monkeys, are characterized by a lack of gut microbial translocation, robust secondary lymphoid natural killer cell responses, and limited SIV dissemination in lymph node B-cell follicles. Using antiretroviral therapy-treated, SIV-infected rhesus monkeys—a pathogenic model—researchers showed that interleukin-21 and interferon alpha therapy generate terminally differentiated blood natural killer cells with potent human leukocyte antigen-E-restricted activity in response to SIV envelope peptides. The correlated reduction of replication-competent SIV in lymph node demonstrates that vervet-like natural killer cell differentiation can be rescued in rhesus monkeys to promote viral clearance. Supported by ORIP (P51OD011132, R24OD010947), NIAID, and NCI.
Cell-Specific Transcriptional Control of Mitochondrial Metabolism by TIF1γ Drives Erythropoiesis
Rossmann et al., Science. 2021.
https://pubmed.ncbi.nlm.nih.gov/33986176/
Transcription and metabolism both influence cell function but dedicated transcriptional control of metabolic pathways that regulate cell fate has rarely been defined. The authors discovered that inhibition of the pyrimidine biosynthesis enzyme dihydroorotate dehydrogenase (DHODH) rescues erythroid differentiation in bloodless zebrafish moonshine (mon) mutant embryos defective for transcriptional intermediary factor 1 gamma (tif1γ). Upon tif1γ loss, CoQ levels are reduced, and a high succinate/α-ketoglutarate ratio leads to increased histone methylation. A CoQ analog rescues mon's bloodless phenotype. These results demonstrate that mitochondrial metabolism is a key output of a lineage transcription factor that drives cell fate decisions in the early blood lineage. Supported by ORIP (R24OD017870), NIGMS, NHLBI, and NCI.
Postpubertal Spermatogonial Stem Cell Transplantation Restores Functional Sperm Production in Rhesus Monkeys Irradiated Before and After Puberty
Shetty et al., Andrology. 2021.
https://onlinelibrary.wiley.com/doi/10.1111/andr.13033
Cancer treatment of prepubertal patients impacts future fertility due to the abolition of spermatogonial stem cells (SSCs). Prepubertal rhesus monkeys (n=6) were unilaterally castrated, and the remaining testes irradiated twice to insure loss of SSCs; the animals were treated with a vehicle or GnRH antagonist for 8 weeks (n=3/treatment). The cryopreserved prepubertal testicular tissue was allergenically transplanted into the intact testes of the monkeys after puberty. Recovery of viable donor epididymal sperm was observed in half the monkeys. These results illustrate that sperm production can be restored in primates by transplantation of testicular cells from cryopreserved untreated prepubertal testes into seminiferous tubules of the remaining testes. Supported by ORIP (P51OD011092), NICHD, and NCI.
Functional Convergence of a Germline-Encoded Neutralizing Antibody Response in Rhesus Macaques Immunized with HCV Envelope Glycoproteins
Chen et al., Immunity. 2021.
https://doi.org/10.1016/j.immuni.2021.02.013
Immunoglobulin heavy chain variable gene IGHV1-69-encoded broadly neutralizing antibodies (bnAbs) targeting the hepatitis C virus (HCV) envelope glycoprotein (Env) E2 are important for protection against HCV infection in humans. An IGHV1-69 ortholog, VH1.36, is preferentially used for bnAbs isolated from rhesus macaques immunized against HCV Env. Researchers investigated the genetic, structural, and functional properties of VH1.36-encoded bnAbs generated by HCV Env vaccination of macaques and compared their findings to IGHV1-69-encoded bnAbs from HCV patients. The investigators found that macaque VH1.36- and human IGHV1-69-encoded bnAbs share many common features, which provides an excellent framework for rational HCV vaccine design and testing. Supported by ORIP (P51OD011133, U42OD010442), NIAID, NCI, and NIGMS.
Establishing an Immunocompromised Porcine Model of Human Cancer for Novel Therapy Development with Pancreatic Adenocarcinoma and Irreversible Electroporation
Hendricks-Wenger et al., Scientific Reports. 2021.
https://pubmed.ncbi.nlm.nih.gov/33828203/
Efficacious interventions to treat pancreatic cancer lack a preclinical model to recapitulate patients' anatomy and physiology. The authors developed RAG2/IL2RG deficient pigs using CRISPR/Cas9 with the novel application of cancer xenograft studies of human pancreatic adenocarcinoma. These pigs were successfully generated using on-demand genetic modifications in embryos. Human Panc01 cells injected into the ears of RAG2/IL2RG deficient pigs demonstrated 100% engraftment. The electrical properties and response to irreversible electroporation of the tumor tissue were found to be similar to excised human pancreatic cancer tumors. This model will be useful to bridge the gap of translating therapies from the bench to clinical application. Supported by ORIP (R21OD027062), NIBIB, and NCI.
New SHIVs and Improved Design Strategy for Modeling HIV-1 Transmission, Immunopathogenesis, Prevention, and Cure
Li et al., Journal of Virology. 2021.
https://doi.org/10.1128/JVI.00071-21
Researchers knew that substitution of HIV-1 Env residue 375-serine by aromatic residues enhances binding to rhesus CD4 enabling primary HIV-1 Envs to support replication as simian-human immunodeficiency virus (SHIV) chimeras in rhesus monkeys. The investigators constructed SHIVs containing 10 primary Envs corresponding to HIV-1 subtypes A, B, C, AE, and AG. Only one with histidine at Env375 replicated efficiently in rhesus cells. Replacement of wild-type Env375 residues by tryptophan, tyrosine, phenylalanine, or histidine in the other 9 SHIVs led to efficient replication. These new SHIVs transmit via mucosal routes like HIV-1 and have use for vaccine testing in nonhuman primates. Supported by ORIP (U42OD021458, P40OD012217), NIAID, and NCI.