Effect of Anti-HIV Therapy (HAART) on HIV Levels in the Lungs and on Lung Cell Inflammation in HIV-Infected Patients

Overview

The purpose of this study is to see: (1) how the amount of HIV in the lungs compares to that in the blood; (2) if HAART reduces the amount of HIV in the lungs; and (3) if HAART reduces lung inflammation in HIV-infected patients. Lung-cell inflammation in HIV-infected patients is probably caused by HIV infection of these cells. The amount of inflammation may correspond to the amount of HIV (viral load) in the lungs (i.e., mild inflammation indicates a low amount of HIV; severe inflammation indicates a high amount of HIV). HAART is used to decrease the amount of HIV in the body. If HAART is able to decrease viral load in the lungs, it should also be able to decrease lung-cell inflammation in these patients.

Lymphocytic alveolitis in HIV-infected patients probably represents a local immune response to HIV-infected cells in the lung. The intensity of lymphocytic alveolitis may therefore reflect the viral load in the lung. If so, treatment that reduces viral load in the lung (e.g., HAART) should also decrease the number of cytotoxic T lymphocytes (CTLs) in the alveolar space and should return pulmonary immune responses toward normal. Patients are stratified by CD4 count: less than 200 cells/mm3 or 200 - 500 cells/mm3. BAL is performed and blood samples are collected prior to initiation of HAART and after 1 and 6 months of HAART. If a patient has detectable HIV in the lung after 6 months of HAART, the patient is asked to submit to an optional fourth BAL after 12 months of HAART. BAL fluid and cells are analyzed for HIV viral load, percent lymphocytes, and lymphocyte subsets. Responses in the lung are compared to simultaneous changes in these variables found in the peripheral blood. Each patient serves as his/her own control.

Conditions