Human a- and b-defensins are cationic, amphipathic effector peptides of the innate immune system with broad antimicrobial, and more recently discovered, antiviral activity. In this Pearls article, Jason Smith and colleagues address some myths assuming that the mechanisms important for bacterial inhibition are also responsible for defensin antiviral activity, as well as identify areas requiring further investigation.
Although mature dendritic cells are vital to combatting viruses and triggering antiviral immune responses, they are also thought to contribute to the viral pathogenesis of HIV-1 through trans-infection. In this Review, Hans-Georg Kräusslich, Javier Martinez-Picado, and colleagues discuss evidence identifying sialyllactosecontaining gangliosides in the viral membrane and the lectin Siglec-1 as critical determinants of HIV-1 capture and storage by mature dendritic cells.
Helicobacter pylori infection promotes stomach ulcers and cancer, although the ways in which the bacteria initially interacts with and irritates gastric tissue is not well understood. Marshall Montrose and colleagues studied H. pylori infection, measuring the accumulation of bacteria at the site of injury, discovering that the bacteria rapidly detects and navigates towards the injury site, colonizing the stomach tissue at injured sites and slowing repair.
Retroviruses have been infecting mammals for at least 100 million years, leaving descendants in host genomes known as endogenous retroviruses (ERVs). Aris Katzourakis, Gkikas Magiorkinis and colleagues built a mathematical model showing that ERV abundance in genomes decreases with larger body size and increases with horizontal transmission, suggesting that larger bodied animals have evolved mechanisms to limit ERV activity.
The Importance of Implementation Strategy in Scaling Up Xpert MTB/RIF for Diagnosis of Tuberculosis in the Indian Health-Care System: A Transmission Model by David Dowdy and colleagues investigate how different implementation strategies for Xpert MTB/RIF, a recently implemented tuberculosis (TB) test, may affect tuberculosis control within the complex fragmented healthcare system of India.
Image credit: Vall d'Hebron Institut de Recerca VHIR, Flickr
Meet Editor-in-Chief Grant McFadden and the PLOS Pathogens team at the International Union of Microbiological Societies Congress in Montréal, Canada July 27- August 1. If you are at the conference, come visit the PLOS booth. Stay tuned @PLOSPathogens on twitter for live updates from PLOS Pathogens and PLOS NTDs editors' talks.
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