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Studying key points on the H.I.V. virus that are weak to immune system attacks could lead to new treatments or H.I.V. vaccines
by applewood

    The Ragon research team tapped into the Protein Data Bank, a database of the three-dimensional structures of protein molecules, for information on 12 of the 15 proteins that make up H.I.V. Using mathematical modeling they identified nodes where the greatest numbers of proteins linked together to form the virus. The complexity of these physical juncture points meant that any changes to the links of these nodes would have the most significant effects on how the virus functions. H.I.V. could mutate at other points to thwart an immune system attack without seriously affecting the virus’s function—but not at these key nodes.

    Then the research team looked at where CD8 T cells, a key part of the immune system, target H.I.V. It turns out that the CD8 T cells of most people take random shots at H.I.V., often hitting parts of the virus that can easily mutate to block the attack.

    But the CD8 T cells of viremic and elite controllers concentrate their attack on the linked nodes where the virus is least capable of mutating to blunt the attack. Ranking the nodes by their connections of proteins and the specific cells on the virus targeted by the immune system produced a network score. The higher the network score, the more successful the CD8 T cells were at controlling the H.I.V. infection—HLA structure did not seem to matter.