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Daniel Acker/Bloomberg via Getty Images

Bird flu test samples at the analytical diagnostics lab at the Iowa State University College of Veterinary Medicine. (Daniel Acker/Bloomberg via Getty Images)


Hazards in the lab

Risky viral research gets a government green light

The United States government has quietly resumed funding for certain high-risk viral experiments that regulators had blocked for four years, according to a February report by Science magazine.

The experiments, known as gain-of-function studies, involve scientists modifying a dangerous virus to make it even more potent and contagious and conducting experiments aimed at finding a vaccine or cure. These experiments often produce highly contagious pathogens potentially capable of wide and uncontrolled spread in human populations. Many scientists fear these deadly viruses could ignite a pandemic if they somehow escaped from the lab or fell into the hands of bioterrorists, and some believe they should be banned.

In 2011 two researchers, Ron Fouchier of Erasmus University Medical Center in the Netherlands and Yoshihiro Kawaoka of the University of Wisconsin in Madison and the University of Tokyo, alarmed the scientific world by revealing they had separately modified the deadly H5N1 bird flu virus so that it spread between ferrets. Many scientists warned the modification might mean the potent virus could also jump to humans.

After a voluntary moratorium by the two researchers’ labs, the experiments resumed in 2013 under new U.S. oversight rules. But concerns reignited after more scientists conducted gain-of-function studies and a series of accidents occurred at federal biocontainment labs. In 2014, U.S. officials announced a pause on federal funding for 18 gain-of-function studies involving influenza, the Middle East respiratory syndrome, and severe acute respiratory syndrome viruses.

In December 2017, the National Institutes of Health lifted the funding pause and invited new gain-of-function research proposals that a safety committee would review. Last year, the committee approved resuming the same type of work in the Fouchier and Kawaoka labs that started the whole debate eight years ago.

Kawaoka told Science he’s glad the government developed new oversight mechanisms and that he can resume his experiments: “We know that it does carry risks. We also believe it is important work to protect human health.”

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Treatment in sight

Non-embryonic stem cells could treat age-related blindness

Nearly 11 million Americans suffer from age-related macular degeneration (AMD), the leading cause of vision loss in people 65 and older. Currently, no cure exists.

But now the federally run National Eye Institute has announced plans to begin human trials of a stem cell therapy to treat the disease, pending FDA approval. The treatment technique avoids the use of embryonic stem cells, which require the destruction of human embryos, and instead uses alternative lab-produced cells called induced pluripotent stem cells (iPSCs). If the human trials gain approval, it will be the first time researchers have used iPSCs to treat a human disease, said National Eye Institute researcher Kapil Bharti in a statement. And since iPSCs are made with a patient’s own cells, they face a minimal chance of rejection once implanted.

In the advanced stages of AMD, retinal pigment epithelial cells (RPEs) begin to die. Light-sensing cells in the retina, or photoreceptor cells, depend on the RPEs to supply them with nutrition and oxygen. When RPEs die, so do the retinal cells, causing blindness.

In animal studies described in the Jan. 16 issue of Science Translational Medicine, the researchers took iPSCs derived from rat and pig blood cells and programmed them to become RPEs. They then grew these cells into small, thin sheets and inserted them into the animals’ eyes between their RPEs and photoreceptor cells. The lab-made RPEs integrated with the animals’ retinas within 10 weeks and kept the remaining photoreceptor cells alive, stopping progression of the disease.

Any stem cell therapy involves the potential risk that the cells will form tumors, but when the researchers analyzed their lab-created cells, they found no mutations that would lead to tumor growth.

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Kevin Van Paassen/Sunnybrook Health Sciences Centre via AP

An Alzheimer’s patient is prepared for ultrasound treatment. (Kevin Van Paassen/Sunnybrook Health Sciences Centre via AP)


Alzheimer’s opening?

Dementia gets the ultrasound treatment

Australian researchers say they are ready to begin testing a promising new treatment for Alzheimer’s disease. The technique, which involves guided ultrasound, could hold out hope for the 44 million people worldwide who suffer from the progressive brain disorder.

Scientists are unsure what causes Alzheimer’s, but they know it involves plaques that form when abnormal amounts of beta-amyloid protein clump together and collect between brain cells. Developing a treatment is difficult because the blood-brain barrier, which protects the brain from infections and toxins, also keeps out many drugs. Also, Alzheimer’s impairs microglial cells in the brain that usually clean up harmful proteins, and the blood-brain barrier blocks components of the immune system that could stimulate the cells back into action.

In 2015 University of Queensland scientists discovered that guided ultrasound could open spots on the blood-brain barrier of mice with Alzheimer’s. The researchers injected harmless microbubbles of air into the bloodstream of the mice, then used MRI to guide ultrasound waves to specific regions of the barrier. The sound waves caused the microbubbles to vibrate and enlarge, temporarily opening up the targeted areas. The procedure cleared almost all of the plaque from 75 percent of the mice, whose memory subsequently improved, the website IFLScience reported.

Another study, published July 25 last year in Nature, tested the safety of the method in five human patients with early to moderate Alzheimer’s. In all five patients the researchers safely opened the blood-brain barrier for less than 24 hours without the use of drugs. The procedure allowed the body’s own natural antibodies to cross the barrier and stimulate glial cells to clean out plaques. The researchers also discovered that the focused ultrasound increased the number of new brain cells in the hippocampus, a brain region involved in learning and memory.

In December the University of Queensland announced that researchers had received Australian funding to test the effectiveness of this approach and planned to begin human trials later this year.

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