Humoral immune factors have been individually studied in the context of host-Aspergillus fumigatus interaction. However, a global view of the multitude and complex nature of humoral factors is needed to bring new insight into the pathobiology of aspergillosis. Therefore, we undertook proteomic analysis of A. fumigatus-infected or colonized bronchoalveolar lavage fluid versus controls, to identify alveolar humoral factors affected upon A. fumigatus infection. Complement proteins C1q, C8 beta chain, factor-H, surfactant protein-D, ficolin-1, ficolin-2, mannan binding lectin serine peptidase 2 and pentraxin-3 were identified as the major candidates. We hypothesize that crosstalk between these factors is essential during host-Aspergillus interaction.