Influenza, Dengue fever, and AIDS are caused by viruses which constantly mutate. And when these viruses mutate, vaccines become ineffective. Current vaccines can provide good protection against particular strains of the virus but fail to protect against new strains caused by genetic mutation. For this reason, tackling this problem is a priority for researchers.
In the latest discovery, scientists at the University of Exeter found that the immune system can deliver memory cells which can perceive distinctive strains of a similar infection, instead of only one. This could enable researchers to change the way antibodies are delivered and given.
The memory cells analyzed in this examination are youthful, or less created, which enables them to all the more effortlessly change and adjust to battle distinctive viral strains. The antibodies from these cells are less centered around the tainting infection, however, this is the favorable position if the infection has transformed.
Dr. Harry White, from the University of Exeter, who led the Wellcome Trust-funded research, said: “Trying to find vaccines which can protect people against different strains of the virus is a focus for scientists around the world. So far, despite a large global effort, there has been a limited success in the war against virus mutation.
“We have found the immune system is able to recognize threats from new strains of a virus. We have long known of the existence of different types of immune memory cells, and now we know what these differences mean.
“After exposure to one strain of a virus, these memory cells are then better able to recognize variants of the virus if they encounter them in the future. The immune system learns to protect against a whole group of related viruses, not just the one it experienced. It is this property that needs to be exploited to help make broadly protective vaccines.”
The research involved academics from the University of Exeter, the University of Bristol and University of Birmingham testing the reaction of mice vaccinated with proteins from different strains of the virus. Through painstakingly isolating hundreds of different individual cells and analyzing the different antibodies each one made they were able to detect the presence of the immature cells that made these less focused antibodies. The mice which were immunized sequentially with proteins from different strains of the same virus produced more of these less developed memory cells.
Professor Rick Titball, from the University of Exeter, said “The holy grail for many scientists is to find a way of developing vaccines which work against all strains of a microorganism. This work could bring us a step closer to this and avoid, for example, the need to develop a new flu vaccine each year.”
The study is published in the journal eLife.