Selected Grantee Publications
Best Practices for Correctly Identifying Coronavirus by Transmission Electron Microscopy
Bullock et al., Kidney International. 2021.
https://pubmed.ncbi.nlm.nih.gov/33493525/
This paper provides strategies for identifying coronaviruses by transmission electron microscopy in ultrathin sections of tissues or tissue cultures. As illustrated by results in the literature, organ damage may be incorrectly attributed to the presence of virus, since images of coronavirus may resemble subcellular organelles. The paper also references numerous biochemical and imaging techniques to aid an investigator in avoiding pseudo positive identifications. Supported by ORIP (S10OD026776) and others.
Cytomegaloviral Determinants of CD8+ T Cell Programming and RhCMV/SIV Vaccine Efficacy
Malouli et al., Science Immunology. 2021.
https://www.science.org/doi/10.1126/sciimmunol.abg5413
Cytomegalovirus (CMV)-based vaccine vectors were developed to leverage the ability of CMVs to elicit sustained CD4+ and CD8+ T cell responses with broad tissue distribution. The 68-1 rhesus cytomegalovirus (RhCMV) vectors that express simian immunodeficiency virus (SIV) inserts induce major histocompatibility complex E (MHC-E)- and MHC-II-restricted, SIV-specific CD8+T cell responses. The contribution of this unconventional MHC restriction to RhCMV/SIV vaccine efficacy are poorly understood. Researchers demonstrated that these responses result from genetic rearrangements in 68-1 RhCMV that disrupt the function of eight immunomodulatory proteins encoded by the virus. Repair of each of these genes with either RhCMV or human CMV counterparts shifted responses to MHC-Ia-restricted, or MHC-Ia- and MHC-II-restricted, CD8 T cell responses, but repairing the RhCMV genes did not protect against SIV. These findings suggest that MHC-E-restricted CD8+ T cell responses may be critical to protection against SIV. Supported by ORIP (U42OD023038, P51OD011092).
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.
Resident Memory T Cells Form During Persistent Antigen Exposure Leading to Allograft Rejection
Abou-Daya et al., Science Immunology. 2021.
https://www.science.org/doi/10.1126/sciimmunol.abc8122
It is not clear whether tissue-resident memory T cells (TRM) function in organ transplants where cognate antigen persists. This is a key question in transplantation as T cells are detected long term in allografts. Investigators showed that antigen-specific and polyclonal effector T cells differentiated in the graft into TRM and subsequently caused allograft rejection. Graft TRM proliferated locally, produced interferon-γ upon restimulation, and their in vivo depletion attenuated rejection. The vast majority of antigen-specific and polyclonal TRM lacked phenotypic and transcriptional exhaustion markers. Single-cell analysis of graft T cells early and late after transplantation identified a transcriptional program associated with transition to the tissue-resident state that could serve as a platform for the discovery of therapeutic targets. Thus, recipient effector T cells differentiate into functional graft TRM that maintain rejection locally. Targeting these TRM could improve renal transplant outcomes. Supported by ORIP (S10OD011925, S10OD019942).
A Novel Tau-Based Rhesus Monkey Model of Alzheimer’s Pathogenesis
Beckman et al., Alzheimer’s & Dementia. 2021.
https://pubmed.ncbi.nlm.nih.gov/33734581/
Alzheimer’s disease (AD) is becoming more prevalent as the population ages, but there are no effective treatments for this devastating condition. Researchers developed a rhesus monkey model of AD by targeting the entorhinal cortex with an adeno-associated virus expressing mutant tau protein. Within 3 months they observed evidence of misfolded tau propagation, similar to what is hypothesized for AD patients. Treated monkeys developed robust alterations in AD core biomarkers in cerebrospinal fluid and blood. These results highlight the initial stages of tau seeding and propagation in rhesus macaques, a potentially powerful translational model with which to test new AD therapies. Supported by ORIP (P51OD011107) and NIA.
A Platform for Experimental Precision Medicine: The Extended BXD Mouse Family
Ashbrook et al., Cell Systems. 2021.
https://www.sciencedirect.com/science/article/abs/pii/S2405471220305032
Systems genetics using rodent models has recently been revitalized thanks to several resources: the BXD family, the Hybrid Mouse Diversity Panel, and the Collaborative Cross. The main limitation has been modest mapping power and precision due to small strain numbers. Investigators expanded the BXD family of mice to 140 fully isogenic strains. Heritable traits can be mapped with precision. Current BXD phenomes include much omics data and thousands of quantitative traits. BXDs can be extended by a single-generation cross up to 19,460 isogenic F1 progeny. This extended BXD family is an effective platform for testing causal modeling and predictive validation. Supported by ORIP (P40OD011102).
A Pulsatile Release Platform Based on Photo-Induced Imine-Crosslinking Hydrogel Promotes Scarless Wound Healing
Zhang et al., Nature Communications. 2021.
https://pubmed.ncbi.nlm.nih.gov/33723267/
Skin wound healing is a dynamic and interactive process involving the collaborative efforts of growth factors, extracellular matrix (ECM), and different tissue and cell lineages. Although accumulating studies with a range of different model systems have increased our understanding of the cellular and molecular basis underlying skin scar formation, they have not been effectively translated to therapy. Development of effective therapeutic approaches for skin scar management is urgently needed. In this study, team of investigators devise a water-oil-water double emulsion strategy to encapsulate proteins within a photo-crosslinkable poly-lactic-co-glycolic acid (PLGA) shell, which can produce microcapsules with pulsatile drug release kinetics after administration. The results show that pulsatile release of the TGF-β inhibitor can accelerate skin wound closure while suppressing scarring in murine skin wounds and large animal preclinical models, suggesting that it could be an effective approach to achieve scarless wound healing in skin. Supported by ORIP (R01OD023700).
Virus Control in Vaccinated Rhesus Macaques Is Associated with Neutralizing and Capturing Antibodies Against the SHIV Challenge Virus but Not with V1V2 Vaccine–Induced Anti-V2 Antibodies Alone
Hessell et al., Journal of Immunology. 2021.
https://doi.org/10.4049/jimmunol.2001010
In the RV144 human immunodeficiency virus (HIV) vaccine trial, the only immune response associated with reduced infection was a high level of antibodies (Abs) targeting the second variable (V2) loop of the HIV envelope protein (Env). The mechanism underlying this suggested contribution of V2 Abs to protection remains unknown. Researchers tested the role of vaccine-induced anti-V2 Abs in rhesus macaques. Three vaccines strategies were designed to induce only V1V2 Abs before simian-human immunodeficiency virus (SHIV) challenge. Vaccine-induced V2 Abs did not independently control SHIV infection. However, neutralizing and virus capture anti-Env Abs were found to correlate with SHIV control. Supported by ORIP (P51OD011092) and NIAID.
Creb5 Establishes the Competence for Prg4 Expression in Articular Cartilage
Zhang et al., Communications Biology. 2021.
https://doi.org/10.1038/s42003-021-01857-0
Cells comprising the superficial zone of articular cartilage express lubricin, encoded by the Prg4 gene, that lubricates joints. Researchers identified Creb5 as a transcription factor that is required for TGF-β and EGFR signaling to induce Prg4 expression. Forced expression of Creb5 in deep-zone chondrocytes of articular cartilage confers competence for TGF-β and EGFR signals to induce Prg4 expression. The researchers showed that Creb5 directly binds to two Prg4 promoter-proximal regulatory elements, which work together with a more distal regulatory element to drive induction of Prg4 by TGF-β. Thus, Creb5 is a critical regulator of Prg4/lubricin expression in the articular cartilage. Supported by ORIP (U42OD11158), NIAMS, and NIDDK.