Rapid HIV evolution evades immune responses
26 Feb 2009
HIV is evolving rapidly to escape the human immune system, an international study has shown. The research was led by scientists at Oxford University, including the James Martin Institute for Emerging Infections and partly funded by the 21st Century School. The findings demonstrate the challenges involved in developing a vaccine capable of keeping pace with the changing nature of the virus.
HIV has already killed 25 million people. However, the virus does not kill all people at the same rate. 'HLA' genes, (which help determine the progress of the HIV virus, and enable the recognition and killing of infected cells) are critically important. Small differences in the type of HLA gene that a patient has can make the difference in how long HIV takes to progress to AIDS.
The study found that HIV is able to mutate when facing the more successful variants of these HLA genes. This "escape mutation" is then transmitted on when another person becomes infected. ‘The implication is that once we have found an effective vaccine, it would need to be changed on a frequent basis to catch up with the evolving virus, much like we do today with the flu vaccine,’ explains lead researcher Professor Philip Goulder.
The James Martin 21st Century School partly funded this collaboration. Professor Rodney Phillips, co-director of the Institute for Emerging Infections, said that his team's contribution was a vindication of the cross disciplinary support received from the 21st Century School, which enables such collaborative and innovative research to take place.
Kawashima Y, Pfafferott K, Frater J, Matthews P, Payne R et al. "Adaptation of HIV-1 to HLA I". is published in Nature, 25 February 2009.