The effect of biomass fuel smoke on pulmonary defence in a population at risk from HIV-related pneumonia. (360G-Wellcome-080065_Z_06_Z)

One third of the world s population uses biomass fuel (burned animal or plant material) for cooking and heating and many of these people are also infected with HIV. Smoke from biomass fuel use is associated with an increased incidence of respiratory infections among adults and children, as is HIV infection. Smoke exposure alters pulmonary defence mechanisms, including macrophage function, cytokine production and epithelial inflammation. The precise mechanism by which BMF smoke increases suscep tibility to respiratory infection and the interaction of these effects with HIV infection, which also causes pulmonary inflammation, are unknown. This study will test the hypothesis that biomass fuel use has an adverse effect on pulmonary defence in HIV infected adults by causing altered macrophage function, lung inflammation and increased HIV replication in pulmonary cells. The effects of BMF particulate exposure on human alveolar macrophages will first be defined in vitro using normal ce lls and then studied in alveolar macrophages from HIV infected and uninfected adults environmentally exposed to BMF in Malawi. HIV viral loads in lung lavage samples obtained from BMF exposed and unexposed HIV infected adults will be compared and the effect of in vitro BMF particulate challenge on viral replication determined.