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Archive - May 25, 2015

Vaccines Using Recombinant Newcastle Disease Virus and Influenza Virus Effective Against Two New Strains of Avian Influenza Virus (H5N1 and H7N9)

A recent study by Kansas State University researchers and colleagues details vaccine development for two new strains of avian influenza that can be transmitted from poultry to humans. The strains have led to the culling of millions of commercial chickens and turkeys, as well as to the deaths of hundreds of people. The new vaccine development method is expected to help researchers make vaccines for emerging strains of avian influenza more quickly. This could reduce the number and intensity of large-scale outbreaks at poultry farms as well as curb transmission to humans. It may also lead to new influenza vaccines for pigs, and novel vaccines for sheep and other livestock, said Dr. Jürgen Richt, Regents Distinguished Professor of Veterinary Medicine and Director of the U.S. Department of Homeland Security's Center of Excellence for Emerging and Zoonotic Animal Diseases. Dr. Richt and his colleagues focused on the avian influenza virus subtype H5N1, a new strain most active in Indonesia, Egypt, and other Southeast Asian and North African countries. H5N1 also has been documented in wild birds in the U.S., though in fewer numbers. "H5N1 is a zoonotic pathogen, which means that it is transmitted from chickens to humans," Dr. Richt said. "So far, it has infected more than 700 people worldwide and has killed about 60 percent of them. Unfortunately, it has a pretty high mortality rate." Researchers developed a vaccine for H5N1 by combining two viruses. A vaccine strain of the Newcastle disease virus, a virus that naturally affects poultry, was cloned and a small section of the H5N1 virus was transplanted into the Newcastle disease virus vaccine, creating a recombinant virus. Tests showed that the new recombinant virus effectively vaccinated chickens against both Newcastle disease virus and H5N1 influenza virus.

Certain Blind Individuals Use Echolocation As Replacement for Vision

Certain blind individuals have the ability to use echoes from tongue or finger clicks to recognize objects in the distance, and some use echolocation as a replacement for vision. Research done by Dr. Mel Goodale, from the University of Western Ontario, in Canada, and colleagues around the world, is showing that echolocation in blind individuals is a full form of sensory substitution, and that blind echolocation experts recruit regions of the brain normally associated with visual perception when making echo-based assessments of objects. Dr. Goodale is Director of the Brain and Mind Institute at the University of Western Ontario. He holds the Canada Research Chair in Visual Neuroscience. Dr. Mel Goodale is the 2015 Presidential Lecturer at the 9th Annual Canadian Neuroscience Meeting. Dr. Goodale's latest results were presented at the 9th Annual Canadian Neuroscience Meeting, on May 24, 2015 in Vancouver British Columbia. This meeting is being held May 24 to 27, 2015. "Our experiments show that echolocation is not just a tool to help visually-impaired individuals navigate their environment, but can act as an effective sensory replacement for vision, allowing them to recognize the shape, size, and material properties of objects," says Dr. Goodale. Just like multiple properties (size, expected weight, texture, composition) of an object assessed by visual cues are encoded in different brain regions, recent research carried out in the Goodale laboratory shows that the same is true of information obtained through the auditory cues provided by echolocation. Indeed, many of the same regions in the sighted brain that are used for the visual assessment of objects are recruited in the blind brain when objects are explored using echolocation.

Plant Receptors with Built-In Decoys Detect Pathogens and Raise Alarm

Receptors carrying built-in decoys are the latest discovery made in studying the evolutionary battle between plants and pathogens. The decoy domains within the receptor detect pathogens and raise the cell's alarm when there is an infection. Plants display component parts of their immune system on receptors to trick pathogens into binding with them, which then triggers defense mechanisms. The discovery comes from Professor Jonathan Jones' group at The Sainsbury Laboratory in the UK, and was published in the May 21, 2015 issue of Cell, together with a companion paper on a similar discovery from Dr. Laurent Deslandes’ group at the CNRS in Toulouse, France. The Jones article is titled “A Plant Immune Receptor Detects Pathogen Effectors that Target WRKY Transcription Factors.” The Deslands article is titled “A Receptor Pair with an Integrated Decoy Converts Pathogen Disabling of Transcription Factors to Immunity.” Pathogens target key parts of the plant's defense machinery in their attempts to suppress an immune response. Plants have evolved to display these targets on receptors that are primed to set off their alarm system. When the pathogen binds, the receptor starts the process of shutting down the cell to contain the pathogen and stop it from spreading. The research from Professor Jones' group shows one way in which plants perceive pathogens. Perception of pathogens is essential for immunity. Plants have very efficient defense mechanisms to stop a pathogen, if they can detect it soon enough. In turn, pathogens are constantly evolving to become stealthier so as to evade perception by the host. This arms race means both plant and pathogen are constantly under pressure to evolve new ways to outwit each other. Scientists now know these ways include the integration of decoy domains within receptors.