Hypoxia triggers an antimicrobial pathway in human alveolar macrophages

Objective: A tuberculous granuloma is a specialized cellular microenvironment with low oxygen tension. Nevertheless immunological studies on the interaction of Mtb and host macrophages are almost exclusively performed under normoxic (20%) conditions. The aim of this study was to investigate whether hypoxia influences the immune response of human alveolar macrophages (AM). Methods: Human AM were purified from bronchoalveolar lavage cells and infected with virulent Mtb. Cytokine release and intracellular growth were compared at different oxygen levels using a hypoxia chamber. Results: The viability and phagocytic…