Fluorocellobiose PET tracer shows strongest signal in live Aspergillus fumigatus infection

A head-to-head comparison of four carbohydrate-based PET tracers has identified 2-deoxy-2-[18F]fluorocellobiose (FCB) as the most promising candidate for imaging live Aspergillus fumigatus infection, according to an open-access original research article published in EJNMMI Research on 15 October 2026. In the study, FCB showed the highest uptake of the four tested tracers in A. fumigatus in vitro and delivered the highest target-to-non-target ratios in PET imaging of a murine A. fumigatus myositis model.

Invasive fungal infections remain a major health concern in immunocompromised patients, largely because diagnosis is often late and unspecific. Pathogen-specific PET radiotracers such as 2-deoxy-2-[18F]fluorocellobiose and 2-deoxy-2-[18F]fluorosorbitol (FDS) have previously shown potential to distinguish between different types of infection. Building on promising in vitro results with L-Rhamnose, the research team developed 2-deoxy-2-[18F]fluoro-L-Rhamnose (F-Rham) as a potential fungus-specific ligand. However, the authors note that direct comparisons across tracers have been limited because different institutions have used inconsistent experimental conditions, which is why the new study evaluated FCB, FDS, F-Rham and 2-deoxy-2-[18F]fluoro-D-glucose (FDG) in identical A. fumigatus animal models, and additionally compared FCB and FDS performance in identical bacterial animal models.

The comparison produced a clear separation between the tracers. Unlike FDG, FCB distinguished live infection from heat-killed inoculations in the murine model, a property the authors link to its potential for detecting metabolically active fungal infection. F-Rham, despite its promising in vitro origins, did not show specific accumulation at either the live or the heat-killed inoculation sites, meaning the newly developed candidate did not perform as hoped in vivo. When FDS and FCB were compared directly, FCB uptake was higher in A. fumigatus than in bacterial infections caused by Escherichia coli and Staphylococcus aureus, whereas FDS preferentially accumulated in E. coli, a pattern observed both in vitro and in vivo.

The authors conclude that FCB shows the highest accumulation in live A. fumigatus infection, while FDS was preferably taken up by E. coli, and that among the tested tracers FCB showed the most promise for successful detection of live A. fumigatus infection when translated to humans. The findings are limited to the preclinical models and tracer set described in the study, and the article is being shared early as a peer-reviewed, accepted version that is citable and carries a permanent DOI, subject to further edits before the final Version of Record. Within those boundaries, the work offers a standardized benchmark for carbohydrate-based fungal PET imaging, suggesting that FCB warrants further evaluation as a pathogen-specific imaging agent for invasive aspergillosis.

Subject of Research: Comparative evaluation of carbohydrate-based PET tracers for imaging Aspergillus fumigatus infection

Article Title: Comparative evaluation of carbohydrate-based PET tracers for Aspergillus fumigatus imaging

Article References: Lai, J., Shah, S., Martinez-Orengo, N., Peiravi, M., Conrad, B., Khan, A. M. A. M., Jones, P. M., Shi, J., Basuli, F., Swenson, R. E., & Hammoud, D. A. (2026). Comparative evaluation of carbohydrate-based PET tracers for Aspergillus fumigatus imaging. EJNMMI Research. https://doi.org/10.1186/s13550-026-01524-7

Image Credits: AI Generated

DOI: 10.1186/s13550-026-01524-7

Keywords: PET imaging, Aspergillus fumigatus, fluorocellobiose, fluorosorbitol, F-Rham, FDG, invasive fungal infection, radiotracers, murine myositis model, E. coli, Staphylococcus aureus, molecular imaging