Grant: Catalyst Grant: HIV/AIDS and Co-morbidities - Biomedical/Clinical

Infection with cytomegalovirus has recently been associated with a phenomenon called immunosenescence in elderly individuals. Our hypothesis is that this relationship is more prominent and develops at an earlier stage in human immunodeficiency virus (HIV)-infected individuals. Immunosenescence is impaired immune system function, which is reflected in inceased susceptibility to infection and poor response to vaccination. Immunosenescence is associated with accumulation of T lymphocytes with certain cell surface markings and most T lymphocytes that react with cytomegalovirus bear these markings. The number of these cells, called end stage cells, increases with age such that the T cell population of elderly individuals becomes dominated by them. It appears that this age-related process is greatly accelerated in HIV infection. We are investigating the relationship between cytomegalovirus infection and accelerated aging of the immune system in HIV infection by characterizing cytomegalovirus-specific T cells and responses to H1N1 influenza vaccination in a group of 80 HIV-infected individuals who received the H1N1 vaccine in 2009.