ISLAMABAD: Plants have been “hijacked” to make polio vaccine in a breakthrough with the potential to transform vaccine manufacture, say scientists. The team at the John Innes Centre, in Norfolk, says the process is cheap, easy and quick. As well as helping eliminate polio, the scientists believe their approach could help the world react to unexpected threats such as Zika virus or Ebola. Experts said the achievement was both impressive and important. The vaccine is an “authentic mimic” of poliovirus called a virus-like particle. Outwardly it looks almost identical to poliovirus but – like the difference between a mannequin and person – it is empty on the inside. It has all the features needed to train the immune system, but none of the weapons to cause an infection. The scientists hijacked a relative of the tobacco plant’s metabolism to turn its leaves into polio-vaccine “factories”. First, they needed to create new instructions for the plant to follow. The starting material was the genetic code for making the outer surface of poliovirus. It was enhanced by combining it with material from viruses that naturally infect plants. The new instructions were then put into soil bacteria, which were used to infect tobacco. The infection took hold, the plants read the genetic instructions and started making the virus-like particles. Infected leaves were mixed with water, blended, and the polio vaccine was extracted. The virus-like particles prevented polio in animal experiments, and an analysis of their 3D structure showed they looked almost identical to poliovirus. Prof George Lomonossoff, from the John Innes Centre, said: “They are incredibly good mimics. It’s a very promising technology, I would hope we get vaccines produced in plants in the not too distant future.” The research is funded by the World Health Organisation, as part of efforts to find replacements for the polio vaccine. Polio – which can cause permanent paralysis – is a thing of the past for most of the world, but the infection has not been eradicated. And using weakened poliovirus in current vaccines poses a risk of the virus regaining some of its dangerous traits – called vaccine-derived poliovirus. Dr Andrew Macadam, principal scientist at the UK’s National Institute for Biological Standards and Control, said: “Current vaccines for polio are produced from large amounts of live virus, which carries a threat of accidental escape and re-introduction. “This study takes us a step closer to replacing current polio vaccines, providing us with a cheap and viable option for making virus-like particle-based vaccines.” Eating late: Eating late at night could increase our skin’s vulnerability to UV damage. Do you get the midnight munchies? If so, new research suggests you might want to take extra care when sunbathing: eating late at night could make your skin more vulnerable to sun damage. According to researchers, mice that were fed during the day rather than at night – which is an abnormal eating pattern for the rodents – experienced greater skin damage as a result of exposure to ultraviolet (UV) radiation, compared with mice fed at normal times. Study co-author Dr Joseph S Takahashi, of the Department of Neuroscience at the University of Texas Southwestern Medical Center in Dallas, and colleagues report that the abnormal eating times altered the circadian rhythm in the skin of the mice, reducing the daytime activity of a skin-protecting enzyme. The findings were recently published in the journal Cell Reports. Whether from the sun or tanning beds, UV rays damage the DNA in skin cells, making UV exposure a major risk factor for sunburn, skin aging, and skin cancer. UVA rays – which account for up to 95 percent of UV rays that reach the Earth’s surface – penetrate the deeper layers of skin. They are a key cause of skin aging, and they also play a role in skin cancer. UVB rays cause most damage to the outer skin layers, and they are the main cause of sunburn and skin cancer. Wearing sun-protective clothing and sunscreen are two of the best ways to protect our skin against the damaging effects of UV radiation. The new study from Dr Takahashi and colleagues, however, suggests that adhering to a normal eating pattern may also help. Activity of skin-protecting enzyme altered: The researchers came to their conclusion by assessing the effects of UVB exposure on the skin of two groups of mice. One group was fed during the daytime only – an abnormal eating time for the nocturnal rodents – while the other group was fed at nighttime only, the usual eating time for mice. The team found that exposure to UVB radiation during the daytime caused greater skin damage in mice whose eating patterns were abnormal, compared with mice that had normal eating patterns. Further investigation revealed that abnormal eating times triggered changes in the circadian rhythm of the rodents’ skin. Specifically, an enzyme called xeroderma pigmentosum group A (XPA) – which normally helps to protect skin against UV damage – became less active in the daytime and more active at nighttime. Mice that followed their normal eating patterns, however, showed no shift in XPA activity. Published in Daily Times, August 20th 2017.