A team of researchers led by the University of California, Berkeley and the University of Michigan has discovered an antibody that blocks the spread of dengue virus, a mosquito-borne pathogen that infects between 50 and 100 million people annually. The virus causes what is known as dengue fever, symptoms of which include fever, vomiting, and muscle pain, and can lead to more serious illness and even death.
There are currently no effective treatments or vaccines for the dengue virus. Because there are four different strains of the virus, building up antibodies to one strain can actually make people more susceptible to subsequent infection by another strain, making it harder to find an effective therapeutic. Scientists using the Advanced Photon Source (APS), a US Department of Energy (DOE) user facility at the DOE's Argonne National Laboratory, have reported success.
Dengue virus uses a specific protein called nonstructural protein 1 (NS1) to attach to the protective cells around organs. It weakens the protective barrier, which allows the virus to infect the cell, and can break blood vessels. The research team's antibody, called 2B7, physically blocks the NS1 protein, preventing it from attaching to cells, and slowing the spread of the virus. In addition, 2B7 is effective against all four strains of dengue virus because it attacks the protein directly and not the virus particle itself.
The research team used X-ray diffraction techniques to determine structures of the NS1 protein with a bound antibody (2B7) and showed how the antibody provides protection against the virus. These diffraction images were recorded at the Structural Biology Facility for General Medicine and Cancer Institutes (GM / CA) of the APS.
The researchers showed that the 2B7 antibody was effective in blocking the spread of dengue virus in living mice. They reported their results in science. The paper suggests that the same antibody could offer new treatments for other flaviviruses like dengue, a group that includes Zika and West Nile.
"Flaviviruses infect hundreds of millions of people and tens of thousands die from related diseases annually," said Bob Fischetti of Argonne, group leader, X-ray science department and life sciences advisor to the APS director. "The protein structures identified at the APS have played a critical role in the development of drugs and vaccines against various diseases. These new results are key to developing a potentially effective treatment against flaviviruses."