Pathogen-specific T cell depletion and reactivation of opportunistic pathogens in HIV infection

Division of Infectious Diseases and Tropical Medicine, Medical Center of University of Munich (LMU), Munich, Germany.
Trends in Immunology (Impact Factor: 12.03). 03/2012; 33(5):207-14. DOI: 10.1016/
Source: PubMed

ABSTRACT During HIV infection, it is unclear why different opportunistic pathogens cause disease at different CD4 T cell count thresholds. Early work has shown that CD4 T cell depletion is influenced both by cellular activation status and expression of viral entry receptors. More recently, functional characteristics of the CD4 T cells, such as cytokine and chemokine production, have also been shown to influence cellular susceptibility to HIV. Here, we examine how functional differences in pathogen-specific CD4 T cells could lead to their differential loss during HIV infection. This may have implications for when different opportunistic infections occur, and a better understanding of the mechanisms for functional imprinting of antigen-specific T cells may lead to improvements in design of vaccines against HIV and opportunistic pathogens.

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