Phase IV Longitudinal Study of Gut Associated Lymphatic Tissue (GALT) in HIV (Human Immunodeficiency Virus)- Infected Patients Before and During Antiretroviral Therapy (ART)

The investigator proposes to evaluate the virological, immunological and clinical outcomes of ART in HIV-1 infected 'late presenters'. The investigator further wants to investigate the longitudinal dynamics of the innate and adaptive immunity restoration in the GALT and peripheral blood of HIV infected patients under ART. In particular the investigators want to longitudinally assess DCs, NK-cells, CD4+ T-cells und CD45RO+-T-cells as well as the levels of IFNγ, IFNα, TNFα, and IL-12 in the GALT and peripheral blood by flow cytometry and by real-time PCR and correlate these data with laboratory and clinical parameters. The investigators expect that this longitudinal study and experiments outlined in the protocol will provide valuable information about several important issues of the clinical outcome of patients under ART as well as understanding immunopathology during HIV-infection.