The immune system is the body’s best defense in fighting diseases like HIV and cancer. Now, an international team of researchers is harnessing the immune system to reveal new clues that may help in efforts to produce an HIV vaccine.
SFU professor Mark Brockman and co-authors from the University of KwaZulu-Natal in South Africa have identified a connection between infection control and how well antiviral T cells respond to diverse HIV sequences.
Brockman explains that HIV adapts to the human immune system by altering its sequence to evade helpful antiviral T cells.
“So to develop an effective HIV vaccine, we need to generate host immune responses that the virus cannot easily evade,” he says.
Brockman’s team has developed new laboratory-based methods for identifying antiviral T cells and assessing their ability to recognize diverse HIV sequences.
“T cells are white blood cells that can recognize foreign particles called peptide antigens,” says Brockman. “There are two major types of T cells-those that ‘help’ other cells of the immune system, and those that kill infected cells and tumours.”
Identifying the T cells that attack HIV antigens sounds simple, but Brockman says three biological factors are critical to a T cell-mediated immune response. And in HIV infection, all three are highly genetically diverse.
He explains that for a T cell to recognize a peptide antigen, the antigen must first be presented on the cell surface by human leukocyte antigen proteins (HLA), which are are inherited.