Gene-edited pigs show signs of resistance to major viral disease

Date: February 23, 2017

Source: University of Edinburgh

 
Scientists have produced pigs that may be protected from an infection that costs the swine industry billions each year.

The team have used advanced genetic techniques to produce pigs that are potentially resilient to Porcine Reproductive and Respiratory Syndrome (PRRS).

Early tests have revealed that cells from the pigs are completely resistant to infection with both major subtypes of the virus that causes the disease.

The animals are otherwise healthy and the change -- introduced using gene-editing technology -- should not affect their ability to fight off other infections, the researchers say.

PRRS causes severe breathing problems in young pigs and breeding failures in pregnant females.

Studies have shown that the PRRS virus targets immune cells called macrophages. A molecule on the surface of these cells called CD163 plays a key role in enabling the PRRS virus to establish an infection.

The research team at the University of Edinburgh's Roslin Institute, in collaboration with Genus, used a gene-editing tool called CRISPR/Cas9 to cut out a small section of the CD163 gene in the pigs' DNA code.



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Bees One of Many Pollinators Infected by Virus Implicated in Colony Collapse Disorder

ScienceDaily (Dec. 28, 2010) — Penn State researchers have found that native pollinators, like wild bees and wasps, are infected by the same viral diseases as honey bees and that these viruses are transmitted via pollen. This multi-institutional study provides new insights into viral infections in native pollinators, suggesting that viral diseases may be key factors impacting pollinator populations.


Their research published on December 22nd in PLoS ONE, an online open-access journal.


According to Diana Cox-Foster, co-author and professor of entomology at Penn State, pollinator populations have declined for various reasons, including ribonucleic acid (RNA) viruses, which are emerging as a serious threat. "RNA viruses are suspected as major contributors to Colony Collapse Disorder (CCD ), where honey bee colonies die with few or no bees left in the hives. Recent detection of these viral species in bumble bees and other native pollinators indicates a possible wider environmental spread of these viruses with potential broader impact," explains Cox-Foster.

The researchers studied viral distributions from pollen pellets of honey bees and other pollinators collected from flowering plants in Pennsylvania, New York, and Illinois in the United States. "For the first time, RNA viruses such as deformed wing virus, sacbrood virus and black queen cell virus were detected in pollen pellets collected directly from forager bees," said Cox-Foster. "Pollen pellets from several uninfected forager bees were detected with virus, indicating that pollen itself may harbor viruses. The viruses in the pollen and honey stored in the hive were demonstrated to be infective, with the queen becoming infected and laying infected eggs after these virus-contaminated foods were given to virus-free colonies."

The detection of RNA viruses in other pollinators, including bumble bees, solitary bees and wasps, suggests that viruses might have a deeper impact on ecosystem health , given that these pollinators are essential to most plants for seed set and production of fruits, nuts, berries, and vegetables. The findings are important to the public and scientific community worldwide, given pollinators' role in agriculture and the environment and recent declines in native pollinators.

The findings also raise biosecurity issues because pollen is currently being imported into many countries to feed honey bees used in agricultural pollination.

http://www.sciencedaily.com/releases/2010/12/101222173037.htm