Research Roundup: Human-sheep chimeras and the organ crisis, clinical trials for an Ebola vaccine developed and tested in animals and more!

Welcome to this week’s Research Roundup. These posts aim to inform our readers about the many stories that relate to animal research each week. Do you have an animal research story we should include in next week’s Research Roundup? You can send it to us via our Facebook page or through the contact form on the website.

  • Scientists grow human cells in sheep for the first time. At the meeting of the American Association for the Advancement of Science, researchers reported that they have introduced human stem cells into sheep embryos. Previous efforts using pig embryos produced embryos for which about one in every 100,000 cells were human. This process has been improved in sheep with a higher efficiency: one in every 10,000 cells. These researchers are, in conjunction, working on a genome editing technique to produce sheep and pig embryos without a pancreas. They hope that the introduced human cells would then grow to replace them missing organs. While there is still much to be done before this research can be used to improve the human organ crisis shortage; it is a promising start.
  • Plastic pollution impacting humans and wildlife. A nearly decade-long study at the University of Alaska — monitoring the ecology of puffins, crested auklets, and other seabirds off the coast of Alaska — suggests 1 in 5 seabirds are contaminated by plastics. Nearly all of the seabirds in the study (200+) tested positive for phthalates in their muscle tissue. Phthalates are plastic chemicals that are widely used in flooring, cosmetics, and medical devices to make plastics more flexible. Phthalates in seabirds implicate phthalates in humans as typical diets in the area include seabird eggs, which contain phthalates. Also, seabirds and humans consume fish and shellfish, which likely contain phthalates. Phthalate exposure in humans is linked to asthma, attention-deficit hyperactivity disorder, breast cancer, type-II diabetes, low IQ, neurodevelopmental issues, autism spectrum disorders, and male fertility issues. The research group is expecting a $30,000 grant from the EPA to continue screening wildlife for phthalates and determining how these forms of plastic are being introduced to the animals.
  • Clues to aging found in fruit flies. The amount of rDNA of fruit flies decreases with age — but can be repaired by reproductive cells. Scientists are now trying to understand this process of repair in the hopes of translation to humans. These researchers observed that rDNA passed on to sons by older fathers was generally reduced in number, compared to younger fathers. Interestingly, within 10 days, sons of older fathers recovered enough rDNA to be comparable to sons born to young fathers. Dr. Yamashita, lead author on this study stated, “These glimpses of perpetual life — cells that can refresh themselves as they move down from father to son — are what fascinate us. By finding hints about how certain cells can continually remain young, the project, touches upon the secret of germ cells’ immortality.” Published in eLife.
D. melanogaster, an orgnaism whose small size belies its huge contribution to medical science. Image courtesy of André Karwath.
  • Aged-fathers give birth to offspring with shorter lifespans. Research in mice suggests that the age of the father at the time of conception is related to the lifespan of the offspring. It is widely recognized that the diet or stress experienced by a potential parent can have negative consequences on their future offspring. Using a mouse model, researchers in Germany found that offspring of aged fathers showed a reduced life span and more pronounced pathologies associated with aging than offspring sired by younger fathers. This finding warrants further investigation, especially into humans. This research was published in PNAS.
  • Ebola vaccine moves closer to clinical trials in humans. Ebola is a major health concern, with an average fatality rate of 50% — and there is no cure. Breakthroughs, using primates, have carved a path forward with proof of efficacy and safety being demonstrated for a live attenuated vaccine. Now, experts at Waisman Biomanufacturing, within the University of Wisconsin–Madison’s Waisman Center, UW–Madison School of Veterinary Medicine, will lead a 3-million dollar effort to produce 1000 doses of his vaccine for clinical trials. This works highlights the crucial role of animal research in the development of safe and efficacious treatments for emergent global health threats.