Selected Grantee Publications
Blastocyst Development After Fertilization with In Vitro Spermatids Derived From Nonhuman Primate Embryonic Stem Cells
Khampang et al., F & Science. 2021.
https://www.sciencedirect.com/science/article/pii/S2666335X21000665?via%3Dihub%C2%A0=
Rhesus macaque pluripotent stem cells were differentiated into spermatogenic germ cell linages and matured in vitro to form spermatids that were capable of fertilizing oocytes (female or germ cells involved in reproduction) by intracytoplasmic spermatid injection (i.e., the egg is fertilized outside the body and the sperm is injected through a needle into the egg). Successful in vitro preimplantation embryo development was observed in approximately 12% of zygotes. The data suggest potential mechanisms to address male infertility. Supported by ORIP (R21OD020182, R01OD028223, P51OD011092).
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.
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.
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.
Lung Expression of Human Angiotensin-Converting Enzyme 2 Sensitizes the Mouse to SARS-CoV-2 Infection
Han et al., American Journal of Respiratory Cell and Molecular Biology. 2021.
https://doi.org/10.1165/rcmb.2020-0354OC
A rapidly deployable mouse model that recapitulates a disease caused by a novel pathogen would be a valuable research tool during a pandemic. Researchers were able to produce C57BL/6J mice with lung expression of human angiotensin-converting enzyme 2 (hACE2), the receptor for SARS-CoV-2. They did so by oropharyngeal delivery of a recombinant human adenovirus type 5 expressing hACE2. The transduced mice were then infected with SARS-CoV-2. Thereafter, the mice developed interstitial pneumonia with perivascular inflammation, exhibited higher viral load in lungs compared to controls, and displayed a gene expression phenotype resembling the clinical response in lungs of humans with COVID-19. Supported by ORIP (P51OD011104, R21OD024931), NHLBI, and NIGMS.