Not to be confused with group presentation. Representation theory is a branch of mathematics that studies abstract algebraic structures by representing their elements as linear transformations of vector spaces, and studies modules over these abstract algebraic structures.
The signature effect of HIV infection, and the cause of AIDS, is disruption of the T-lymphocyte branch of the immune system and in particular the destruction of CD4+ T-helper cells.
HIV is a unique human RNA virus, capable of infecting cells of the immune system. Specifically, HIV targets T helper cells (CD4 cells), leading to the eventual death of the cell. CD4 cells are vital players in the regulation of immune responses to invading microorganisms.