Domain: plospathogens.org
Stories and comments across the archive that link to plospathogens.org.
Stories · 3
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How Did the 'Berlin Patient' Rid Himself of HIV?
sciencehabit writes: Researchers are closer to unraveling the mystery of how Timothy Ray Brown, the only human cured of HIV, defeated the virus, according to a new study. Although the work doesn't provide a definitive answer, it rules out one possible explanation. [R]esearchers point to three different factors that could independently or in combination have rid Brown’s body of HIV. The first is the process of conditioning, in which doctors destroyed Brown’s own immune system with chemotherapy and whole body irradiation to prepare him for his bone marrow transplant. His oncologist, Gero Hütter, who was then with the Free University of Berlin, also took an extra step that he thought might not only cure the leukemia but also help rid Brown’s body of HIV. He found a bone marrow donor who had a rare mutation in a gene that cripples a key receptor on white blood cells the virus uses to establish an infection. (For years, researchers referred to Brown as "the Berlin patient.") The third possibility is his new immune system attacked remnants of his old one that held HIV-infected cells, a process known as graft versus host disease. -
First Lab Demonstration That the Ability To Evolve Can Itself Evolve
ananyo writes "Research on Borrelia burgdorferi, the bacterium that causes Lyme disease, shows that the capacity to evolve can itself be the target of natural selection. B. burgdorferi can cause a chronic infection even if its animal host mounts a strong immune response — evading those defenses by tweaking the shape and expression of its main surface antigen, VIsE. A series of unexpressed genetic sequences organized into 'cassettes' recombine with the VIsE gene, changing the resulting protein such that it escapes detection by the host's immune system. The researchers studied the molecular evolution of the cassettes' genetic sequences in 12 strains of B. burgdorferi. They found that natural selection seemed to favor bacteria with more genetic variability within their cassettes, and hence a greater capacity to generate different versions of the antigen. 'Greater diversity among the cassettes in itself shouldn't be a selective advantage considering they aren't expressed and don't do anything else,' says lead author Dustin Brisson. 'But we did find evidence of selection, so the question is: what else could it be for besides evolvability?'" -
New Virus Jumps From Monkeys To Lab Workers
sciencehabit writes "It started with a single monkey coming down with pneumonia at the California National Primate Research Center in Davis. Within weeks, 19 monkeys were dead and three humans were sick. Now, a new report confirms that the Davis outbreak was the first known case of an adenovirus jumping from monkeys to humans. The upside: the virus may one day be harnessed as a tool for gene therapy."