Scientists have found that the human immunodeficiency virus (HIV) can adapt to the body's defense system, thereby AIDS vaccine must consider the ever-changing immunological profile of the virus.
Researchers at the University of Alabama at Birmingham (UAB) and the University of Oxford in England conducted a study that showed HIV adapts by spelling out at least 14 different "escape mutations" that help keep it alive after it interacts genetically with immunity molecules that normally attack the virus.
The researchers revealed that they analysed genetic data from more than 2,800 HIV-infected patients on five continents.
"Key genetic regions of HIV introduced into individuals of different ancestry in different places have been evolving to a greater or lesser degree according to inherited factors controlling immune response," Nature magazine quoted Dr. Richard Kaslow, a professor in the UAB School of Public Health and a co-author of the study, as saying.
"If HIV adapts differently in genetically distinct hosts, the challenge ahead in vaccine design is formidable," he added.
The team focused on different DNA variations of HIV in conjunction with different forms of human leukocyte antigen (HLA), a group of molecules that orchestrate immune response.
HLA molecules generally present fragments of HIV proteins on the surface of infected cells to the immune system, acting as a signal for HIV destruction.
Kaslow said that his team's work showed how efficiently the virus evolves escape mutations that help infected cells avoid destruction.
Study's senior author Dr. Philip Goulder, a professor of immunology at the University of Oxford, said that the future of vaccine exploration would need to address the escape mutation capacity, and identify new drug targets that work against an ever-changing HIV immunology landscape.