Shiloh
Editor, Senior Moderator
Source: http://www.physorg.com/news192371871.html
New understanding of dengue fever could help with vaccine
May 6, 2010
Some of the human immune system's defences against the virus that causes dengue fever actually help the virus to infect more cells, according to new research published today in the journal Science.
The researchers behind the work, from Imperial College London, hope their new findings could help with the design of a vaccine against the dengue virus. The study also brings scientists closer to understanding why people who contract dengue fever more than once usually experience more severe and dangerous symptoms the second time around...
...The researchers behind today's study have identified a set of antibodies, produced by the human immune system to fight off the dengue virus, that they believe scientists should avoid including in any new vaccine to prevent dengue fever.
The new research shows that these precursor membrane protein (prM) antibodies do not do a very effective job of neutralising the virus. Moreover, these antibodies actually help the virus to infect more cells.
The study suggests that when a person who has already been infected with one strain of dengue virus encounters a different strain of dengue virus, the prM antibodies awakened during the first infection spring into action again. However, rather than protecting the body from the second infection, these prM antibodies help the virus to establish itself.
This activity of the prM antibodies could explain why a second infection with a different strain of the virus can cause more harm than the first infection. The researchers believe that if a dengue virus vaccine contained prM antibodies, this could cause similar problems...
..."Our new research gives us some key information about what is and what is not likely to work when trying to combat the dengue virus. We hope that our findings will bring scientists one step closer to creating an effective vaccine," he added.
The researchers reached their conclusions after analysing individual antibodies to the dengue virus extracted from blood samples donated by infected volunteers.
More information: "Cross-reacting Antibodies Enhance Dengue Virus Infection in Humans" Science, Thursday 6 May 2010.
New understanding of dengue fever could help with vaccine
May 6, 2010
Some of the human immune system's defences against the virus that causes dengue fever actually help the virus to infect more cells, according to new research published today in the journal Science.
The researchers behind the work, from Imperial College London, hope their new findings could help with the design of a vaccine against the dengue virus. The study also brings scientists closer to understanding why people who contract dengue fever more than once usually experience more severe and dangerous symptoms the second time around...
...The researchers behind today's study have identified a set of antibodies, produced by the human immune system to fight off the dengue virus, that they believe scientists should avoid including in any new vaccine to prevent dengue fever.
The new research shows that these precursor membrane protein (prM) antibodies do not do a very effective job of neutralising the virus. Moreover, these antibodies actually help the virus to infect more cells.
The study suggests that when a person who has already been infected with one strain of dengue virus encounters a different strain of dengue virus, the prM antibodies awakened during the first infection spring into action again. However, rather than protecting the body from the second infection, these prM antibodies help the virus to establish itself.
This activity of the prM antibodies could explain why a second infection with a different strain of the virus can cause more harm than the first infection. The researchers believe that if a dengue virus vaccine contained prM antibodies, this could cause similar problems...
..."Our new research gives us some key information about what is and what is not likely to work when trying to combat the dengue virus. We hope that our findings will bring scientists one step closer to creating an effective vaccine," he added.
The researchers reached their conclusions after analysing individual antibodies to the dengue virus extracted from blood samples donated by infected volunteers.
More information: "Cross-reacting Antibodies Enhance Dengue Virus Infection in Humans" Science, Thursday 6 May 2010.