Two Monoclonal Antibodies That Specifically Recognize Aspergillus Cell Wall Antigens and Can Detect Circulating Antigens in Infected Mice

Invasive aspergillosis (IA) is a life-threatening disease mainly caused by and . Early diagnosis of this condition is crucial for patient treatment and survival. As current diagnostic techniques for IA lack sufficient accuracy, we have raised two monoclonal antibodies (1D2 and 4E4) against cell wall fragments that may provide a platform for a new diagnostic approach. The immunoreactivity of these antibodies was tested by immunofluorescence and ELISA against various and species in vitro and by immunohistochemistry in infected mouse tissues. Both monoclonal antibodies (mAbs) showed intensive fluorescence with the hyphae wall of and , but there was no staining with other species or species. Both mAbs also showed strong immunoreactivity to the cell wall of hyphae in the infected liver, spleen and kidney of mice with IA. The antigens identified by 1D2 and 4E4 might be glycoproteins and the epitopes are most likely a protein or peptide rather than a carbohydrate. An antibody-based antigen capture ELISA detected the extracellular antigens released by , , and , but not in species. The antigen could be detected in the plasma of mice after 48 h of infection by double-sandwich ELISA. In conclusion, both 1D2 and 4E4 mAbs are potentially promising diagnostic tools to investigate invasive aspergillosis.