Abstract
Biobanks containing formalin-fixed, paraffin-embedded (FFPE) tissues from animals and human atomic-bomb survivors exposed to radioactive particulates remain a vital resource for understanding the molecular effects of radiation exposure. These samples are often decades old and prepared using harsh fixation processes which limit sample imaging options. Optical imaging of hematoxylin and eosin (H&E) stained tissues may be the only feasible processing option, however, H&E images provide no information about radioactive microparticles or radioactive history. Synchrotron X-ray fluorescence microscopy (XFM) is a robust, non-destructive, semi-quantitative technique for elemental mapping and identifying candidate chemical element biomarkers in FFPE tissues. Still, XFM has never been used to uncover distribution of formerly radioactive micro-particulates in FFPE canine specimens collected more than 30 years ago. In this work, we demonstrate the first use of low-, medium-, and high-resolution XFM to generate 2D elemental maps of ~ 35-year-old, canine FFPE lung and lymph node specimens stored in the Northwestern University Radiobiology Archive documenting distribution of formerly radioactive micro-particulates. Additionally, we use XFM to identify individual microparticles and detect daughter products of radioactive decay. The results of this proof-of-principle study support the use of XFM to map chemical element composition in historic FFPE specimens and conduct radioactive micro-particulate forensics.
| Original language | English |
|---|---|
| Article number | 7806 |
| Journal | Scientific Reports |
| Volume | 13 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2023 |
Funding
Funding for this project is provided by grants from the Department of Defense (W81XWH-21–1-0984) and by National Institutes of Health, National Institute of Allergy and Infectious Diseases (1P01AI165380-01). Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science under contract No. DE-AC02-06CH11357. The BNP was obtained with an NIH ARRA S10 grant no. SP0007167. S.C. acknowledges the support of DOE grant no. PRJ1009594. This work was also supported by the Northwestern University Pathology Core Facility and a Cancer Center Support Grant (NCI CA060553). We would also like to thank Peter Zieba for help with elemental ROI analyses and acknowledge the work completed by Inhalation Toxicology Research Institute and National Radiobiology Archives researchers that made this study possible.