Selected Grantee Publications
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- 27 results found
- Preservation
- Spectrometry
Effects of Ex Vivo Blood Anticoagulation and Preanalytical Processing Time on the Proteome Content of Platelets
Yunga et al., Journal of Thrombosis and Haemostasis. 2022.
https://www.doi.org/10.1111/jth.15694
The investigators studied how various blood anticoagulation options and processing times affect platelet function and protein content ex vivo. Using platelet proteome quantification and triple quadrupole mass spectrometry, they found that anticoagulant-specific effects on platelet proteomes included increased complement system and decreased α-granule proteins in platelets from EDTA-anticoagulated blood. Heparinized blood had higher levels of histone and neutrophil-associated proteins, as well as formation of platelet–neutrophil extracellular trap interactions in whole blood ex vivo. The study indicates that different anticoagulants and preanalytical processing times affect platelet function and platelet protein content ex vivo, suggesting more rigorous phenotyping strategies for platelet omics studies. Supported by ORIP (S10OD012246), NHLBI, NCI and NEI.
Phase Separation Drives Aberrant Chromatin Looping and Cancer Development
Ahn et al., Nature. 2021.
https://doi.org/10.1038/s41586-021-03662-5
How unstructured intrinsically disordered regions (IDRs) contribute to oncogenesis is elusive. Using an Orbitrap fusion tribrid mass spectrometer, investigators show that IDRs contained within NUP98–HOXA9, a homeodomain-containing transcription factor chimera recurrently detected in leukaemias, are essential for establishing liquid–liquid phase separation (LLPS) puncta of chimera and for inducing leukaemic transformation. LLPS of NUP98–HOXA9 not only promotes chromatin occupancy of chimera transcription factors, but also is required for the formation of a broad “super-enhancer”-like binding pattern typically seen at leukaemogenic genes, which potentiates transcriptional activation. An artificial HOX chimera, created by replacing the phenylalanine and glycine repeats of NUP98 with an unrelated LLPS-forming IDR of the FUS protein, had similar enhancing effects on the genome-wide binding and target gene activation of the chimera. This report describes a proof-of-principle example in which cancer acquires mutation to establish oncogenic transcription factor condensates via phase separation, which simultaneously enhances their genomic targeting and induces organization of aberrant three-dimensional chromatin structure during tumor transformation. Supported by ORIP (S10OD018445).
Nonhuman Primate Models for SARS-CoV-2 Research: Cryopreservation as a Means to Maintain Critical Models and Enhance the Genetic Diversity of Colonies
Arnegard and Hild et al., Lab Animal. 2021.
https://doi.org/10.1038/s41684-021-00792-1
This commentary, written by ORIP staff, addresses the need for improved cryopreservation methods and resources for nonhuman primate (NHP) gametes and embryos to safeguard newly developed NHP models and enhance the genetic diversity of NHP colonies without reliance on animal importations. Cryopreservation also plays critical roles in medical approaches to preserve the fertility of patients who must undergo potentially gonadotoxic treatments, as well as nascent genome editing efforts to develop new NHP models for human diseases. Given these diverse benefits to research progress, ORIP continues to fund the development of cryopreservation tools and approaches for NHPs and other animal models.
Cryopreservation and Preparation of Thawed Spermatozoa from Rhesus Macaques (Macaca mulatta) for In Vitro Fertilization
De Carvalho et al., Journal of the American Association for Laboratory Animal Science. 2021.
https://www.ingentaconnect.com/content/aalas/jaalas/pre-prints/content-jaalas-20-000028
Optimizing procedures for cryopreservation and subsequent thawing for rhesus macaques is required to prevent cryodamage that negatively impacts artificial insemination and in vitro fertilization rates. Investigators systematically assessed two cryopreservation methods and four recovery methods in three interdependent experiments. Results demonstrated that slow-freezing, coupled with density gradient centrifugation provided the highest efficacy in functional sperm for in vitro use. Additional studies are required to further optimize sperm cryopreservation in rhesus macaques. Supported by ORIP (P51OD011092).
Cryopreservation Method for Drosophila melanogaster Embryos
Zhan et al., Nature Communications. 2021.
https://www.nature.com/articles/s41467-021-22694-z
Drosophila melanogaster is a premier model for biomedical research. However, preservation of Drosophila stocks is labor intensive and costly. Researchers at University of Minnesota reported an efficient method for cryopreservation by optimizing key steps including embryo permeabilization and cryoprotectant agent loading. This method resulted in more than 10% of embryos developing into fertile adults after cryopreservation for 25 distinct strains from different sources. The further optimization and wide adoption of this protocol will solve the long-standing issue in reliably preserving Drosophila stocks and will significantly impact Drosophila as a model organism for biomedical research. Supported by ORIP (R21OD028758) and NIGMS.
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.
3-D Printed Customizable Vitrification Devices for Preservation of Genetic Resources of Aquatic Species
Tiersch et al., Aquacultural Engineering. 2020.
https://www.sciencedirect.com/science/article/pii/S0144860920300406
Sperm vitrification as an alternative approach to conventional cryopreservation allows quick and low-cost sample preservation and is suitable for small-bodied aquatic species with miniscule testis, fieldwork at remote locations, and small-scale freezing for research purposes. Tiersch et al. report the developing of operational prototypes of 3-dimensional (3-D) printed vitrification devices. This study demonstrated the feasibility of developing standardized low-cost devices fabricated by 3-D printing with functions including vitrification, volume control, labeling, protection, and storage. These prototypes can be further developed to assist development of germplasm repositories to protect the genetic resources of aquatic species by breeders, hatcheries, aquariums, and researchers. Supported by ORIP (R24OD010441).