68Ga-Triacetylfusarinine C and 68Ga-Ferrioxamine E for Aspergillus Infection Imaging: Uptake Specificity in Various Microorganisms

Ga-68-triacetylfusarinine C (Ga-68-TAFC) and Ga-68-ferrioxamine E (Ga-68-FOXE) showed excellent targeting properties in Aspergillus fumigatus rat infection model. Here, we report on the comparison of specificity towards different microorganisms and human lung cancer cells (H1299). The in vitro uptake of Ga-68-TAFC and Ga-68-FOXE was studied in various fungal, bacterial and yeast cultures as well as in H1299 cells. The in vivo imaging was studied in fungal and bacterial rat infection and inflammation models. Ga-68-TAFC and Ga-68-FOXE showed rapid uptake in A. fumigatus cultures, significantly lower in other fungal species and almost no uptake in other microorganisms and H1299 cells, except for Ga-68-FOXE in Staphylococcus aureus. Ga-68-TAFC and Ga-68-FOXE revealed rapid uptake in the lungs of A. fumigatus-infected rats, low accumulation in sterile inflammation and no uptake in bacterial abscess. We have shown that Ga-68-FOXE and Ga-68-TAFC have high uptake in A. fumigatus both in vitro and in vivo. Ga-68-TAFC showed higher specificity, while Ga-68-FOXE showed higher sensitivity.