Imaging of fungal infections

简介:

Summary: We have been pursuing three main approaches to developing radiolabeled fungal specific ligands for in vivo diagnosis: 1. Evaluation of existing ligands: we have tested 18F-fluorodeoxysorbitol which has been described as an appropriate ligand for gram negative bacteria. We found that there was mild uptake by aspergillus species however this was not high enough for accurate diagnosis. We published our results in J Fungi in 2022. 2. Evaluation of radiolabeled sugars: we are currently evaluating two potential ligands: 18F-Cellobiose and Trehalose. Results pending. 3. Using radiolabeled antibodies and nanobodies specific for chitin and laminarin: we are currently evaluating a full antibody against fungal cell component laminarin as well as Fab Fragment. Although we found uptake of labeled antibody in fungal infection, we also saw uptake of an isotype antibody to the same extent suggesting antibodies are too large and end up accumulating nonspecifically in areas of inflammation due to increased endothelial permeability. When we used Fab antibody fragments, we found uptake of the Fab in the infected animals but no uptake in uninfected animals. Isotype Fab did not accumulate neither in infected nor in uninfected animals. We are also evaluating single chain antibodies (nanobodies) to improve the specificity of targeting fungal infections. Results pending.