Monocytic Cell Responses to Aspergillus Fumigatus: Investigation of Phagocytosis, Gene Expression andPeptide Presentation

Aspergillus fumigatus is a member of a large genus offilamentous fungi found in the environment. It ispathogenic to humans, causing life-threateninginfections in immunocompromised patients, likeleukemia and bone-marrow transplant patients. Thisstudy was initiated to investigate a stilllittle-researched field in immune response againstthis pathogenic fungus: the role of monocytes. We therefore analyzed the interaction of Aspergillusfumigatus with human monocytes on different levels.We investigated Phagocytosis of fungal spores andperformed gene expression analysis using microarraygene chips. In a second effort we analyzed peptidespresented on monocytes upon interaction with the fungus. We could show monocytes to play a major role inphagocytosing fungal spores and that Asp. fumigatusinduces inflammatory response in monocytes, which maylead to lung injury, a phenomenon observed often inpatients with invasive aspergillosis.