Selected Grantee Publications
A Participant-Derived Xenograft Model of HIV Enables Long-Term Evaluation of Autologous Immunotherapies
McCann et al., Journal of Experimental Medicine. 2021.
https://doi.org/10.1084/jem.20201908
HIV-specific CD8+ T cells partially control viral replication but rarely provide lasting protection due to immune escape. Investigators showed that engrafting NSG mice with memory CD4+ T cells from HIV+ donors enables evaluation of autologous T cell responses while avoiding graft-versus-host disease. Treating HIV-infected mice with clinically relevant T cell products reduced viremia. In vivo activity was significantly enhanced when T cells were engineered with surface-conjugated nanogels carrying an Interleukin-15 superagonist but was ultimately limited by the pervasive selection of escape mutations, recapitulating human patterns. This “participant-derived xenograft” model provides a powerful tool for developing T cell-based therapies for HIV. Supported by ORIP (R01OD011095), NIAID, NIDA, NIMH, NINDS, and NCATS.
Psychosocial Stress Alters the Immune Response and Results in Higher Viral Load During Acute SIV Infection in a Pigtailed Macaque Model of HIV
Guerrero-Martin et al., Journal of Infectious Diseases. 2021.
https://doi.org/10.1093/infdis/jiab252
Social distancing is an important countermeasure for a pandemic, but social isolation may also have adverse health outcomes in the context of infectious diseases, such as HIV. Researchers compared commonly measured parameters of HIV progression between singly and socially housed simian immunodeficiency virus (SIV)-infected pigtailed macaques. Throughout acute SIV infection, singly housed pigtailed macaques had a higher viral load in the plasma and cerebrospinal fluid and demonstrated greater CD4+ T cell declines and more CD4+ and CD8+ T cell activation compared to socially housed macaques. These findings suggest that psychosocial stress could augment the progression of HIV infection. Supported by ORIP (U42OD013117, P40OD013117, K01OD018244), NIAID, NINDS, and NIMH.
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.
Evidence in Primates Supporting the Use of Chemogenetics for the Treatment of Human Refractory Neuropsychiatric Disorders
Roseboom et al., Molecular Therapy. 2021.
https://doi.org/10.1016/j.ymthe.2021.04.021
A rhesus macaque model for pathological anxiety was used to investigate the feasibility of decreasing anxiety using chemogenetics, known as DREADDs (designer receptors exclusively activated by designer drugs), to reduce amygdala neuronal activity. A low-dose clozapine administration strategy was developed to induce DREADD-mediated amygdala inhibition. Compared to controls, clozapine selectively decreased anxiety-related freezing behavior in the human intruder paradigm in the chemogentic monkeys, while coo vocalizations and locomotion were unaffected. These results are an important step in establishing chemogenetic strategies for patients with refractory neuropsychiatric disorders in which amygdala alterations are central to disease pathophysiology. Supported by ORIP (P51OD011106), NIMH, and NICHD.
The High Affinity Dopamine D2 Receptor Agonist MCL-536: A New Tool for Studying Dopaminergic Contribution to Neurological Disorders
Subburaju et al., ACS Chemical Neuroscience. 2021.
https://pubs.acs.org/doi/full/10.1021/acschemneuro.1c00094
The dopamine D2 receptor exists in two different states, D2high and D2low; the former is the functional form of the D2 receptor and associates with intracellular G-proteins. The D2 agonist [3H]MCL-536 has high affinity for the D2 receptor (Kd 0.8 nM) and potently displaces the binding of (R-(-)-N-n-propylnorapomorphine (NPA; Ki 0.16 nM) and raclopride (Ki 0.9 nM) in competition binding assays. The authors characterized [3H]MCL-536. [3H]MCL-536 as metabolically stable. In vitro autoradiography on transaxial and coronal brain sections showed specific binding of [3H]MCL-536. [3H]MCL-536's unique properties make it a valuable tool for research on neurological disorders like Parkinson's disease or schizophrenia. Supported by ORIP (R43OD020186, R44OD024615) and NIMH.
Rhesus Macaques Build New Social Connections After a Natural Disaster
Testard et al., Current Biology. 2021.
https://www.sciencedirect.com/science/article/pii/S0960982221003687
Climate change has increased the frequency and intensity of weather-related disasters such as hurricanes and floods. In 2017, Puerto Rico suffered its worst natural disaster, Hurricane Maria, leaving 3,000 dead and provoking a mental health crisis. Cayo Santiago Island, home to a population of rhesus macaques (Macaca mulatta), was devastated by this storm. Testard et al. compared social networks of two groups of macaques before and after the hurricane and found an increase in affiliative social connections, driven largely by monkeys most socially isolated before Hurricane Maria. Further analysis revealed monkeys invested in building new relationships rather than strengthening existing ones. Supported by ORIP (P40OD012217), NIA, and NIMH.
The SARS-CoV-2 Receptor and Other Key Components of the Renin-Angiotensin-Aldosterone System Related to COVID-19 are Expressed in Enterocytes in Larval Zebrafish
Postlethwait et al., Biology Open. 2021.
https://bio.biologists.org/content/10/3/bio058172.article-info
Hypertension and respiratory inflammation are exacerbated by the Renin-Angiotensin-Aldosterone System (RAAS), which normally protects from dropping blood pressure via Angiotensin II (Ang II) produced by the enzyme Ace. The Ace paralog Ace2 degrades Ang II and serves as the SARS-CoV-2 receptor. To exploit zebrafish to understand the relationship of RAAS to COVID-19, the group conducted genomic and phylogenetic analyses. Results identified a type of enterocyte as the expression site of zebrafish orthologs of key RAAS components, including the SARS-CoV-2 co-receptor. Results identified vascular cell subtypes expressing Ang II receptors and identified cell types to exploit zebrafish as a model for understanding COVID-19 mechanisms. Supported by ORIP (R24OD026591, R01OD011116), NIGMS, NICHD.
Metabolomics Analysis of Follicular Fluid Coupled With Oocyte Aspiration Reveals Importance of Glucocorticoids in Primate Periovulatory Follicle Competency
Ravisankar et al., Scientific Reports. 2021.
https://www.nature.com/articles/s41598-021-85704-6
Assisted reproductive therapy in primates requires ovarian stimulation protocols, which result in multiple heterogeneous oocytes with variable capacity for fertilization, cleavage, and blastocyst formation. Recovered oocytes from rhesus macaque follicles (n=74 follicles) were fertilized in vitro and classified as failed to cleave, cleaved but arrested, or able to form blastocysts. Metabolomics analysis of the follicular fluid identified 60 metabolites that were different among embryo classifications; key was an increase in the intrafollicular ratio of cortisol to cortisone in the blastocyst group, which was associated with translocation of the glucocorticoid receptor, NR3C1. The data suggest a role for NR3C1 in the regulation of follicular processes, such as expansion of cumulus granulosa cells, via paracrine signaling. Supported by ORIP (P51OD011092) and NICHD.
A Chromosome-Level Genome of Astyanax mexicanus Surface Fish for Comparing Population-Specific Genetic Differences Contributing to Trait Evolution
Warren et al., Nature Communications. 2021.
https://pubmed.ncbi.nlm.nih.gov/33664263/
Identifying the genetic factors that underlie complex traits is central to understanding the mechanistic underpinnings of evolution. Cave-dwelling Astyanax mexicanus populations are well adapted to subterranean life and many populations appear to have evolved troglomorphic (morphological adaptation of an animal to living in the constant darkness of caves) traits independently, while the surface-dwelling populations can be used as a proxy for the ancestral form. Warren et al. present a high-resolution, chromosome-level surface fish genome, enabling the first genome-wide comparison between surface fish and cavefish populations. Using this resource, they performed quantitative trait locus (QTL) mapping analyses and found new candidate genes for eye loss (dusp26). They also generated the first genome-wide evaluation of deletion variability across cavefish populations to gain insight into this potential source of cave adaptation. The surface fish genome reference now provides a more complete resource for comparative, functional and genetic studies of drastic trait differences within a species. Supported by ORIP (R24OD011198), NIA, NICHD, NIGMS, amd NIDCR.
Autologous Transplant Therapy Alleviates Motor and Depressive Behaviors in Parkinsonian Monkeys
Tao et al., Nature Medicine. 2021.
https://www.nature.com/articles/s41591-021-01257-1
Generation of induced pluripotent stem cells (iPSCs) enables standardized of dopamine (DA) neurons for autologous transplantation therapy to improve motor functions in Parkinson disease (PD). Adult male rhesus PD monkeys receiving autologous, but not allogenic, transplantation exhibited recovery from motor and depressive signs of PD over a 2-year period without immunosuppressive therapy. Mathematical modeling showed correlations between surviving DA neurons with PET signal intensity and behavior recovery regardless of autologous or allogeneic transplant, suggesting a predictive power of PET and motor behaviors for surviving DA neuron number. The results demonstrate favorable efficacy of the autologous transplant approach to treat PD. Supported by ORIP (P51OD011106) NINDS, and NICHD.