Scientists have discovered that the Lassa virus, which is endemic to West Africa, uses an unexpected two-step process to enter cells. The results, published in today's edition of the journal Science, suggest that the mechanism by which Lassa virus causes infection is more complicated than previously known.
An international team of scientists from the Netherlands Cancer Institute, Harvard Medical School, the University of Kiel in Germany, and the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) collaborated on the study, which could lead to new approaches for preventing the disease.
"This research indicates that viruses may require multiple receptors for delivering their viral cargo for productive infection, which is a fresh way of looking at classical viral entry," said John M. Dye, Jr., Ph.D, of USAMRIID.
According to the authors, it has been known for more than three decades that while Lassa virus can infect a broad range of cells from different species, it does not infect chickensdespite the fact that bird cells have the necessary receptor, or protein, that the virus uses to enter cells. Thus, some additional mechanism appeared to be at work.
Scientists at the Netherlands Cancer Institute and Harvard Medical School discovered that when Lassa virus latches on to its receptor on the cell surface, it is first transported to a structure inside the cell called a lysosome. Lysosomes have been dubbed the "garbage cans" of cells because they break down a variety of molecules. Therefore, in order to infect the cell, Lassa virus needs to escape the lysosome. It does so by hooking onto a protein called LAMP1a previously undiscovered interior cell receptor for the virus.
"From a virology point of view, this second part of our discovery is the most interesting," said first author Lucas Jae of the Netherlands Cancer Institute. "The identity of the receptor on the cell surface has been known for
|Contact: Caree Vander Linden|
US Army Medical Research Institute of Infectious Diseases