Scintigraphic detection of pulmonary aspergillosis in rabbits with a radiolabeled leukotriene b4 antagonist.

Abstract

UNLABELLED:

Radiolabeled chemotactic peptides have been studied for their applicability to the visualization of infectious and inflammatory foci. Because a radiolabeled leukotriene B4 (LTB4) antagonist allowed visualization of intramuscular E. coli abscesses in rabbits within a few hours after injection, we decided to test the imaging characteristics of this agent in a more clinically relevant model of pulmonary aspergillosis. The pharmacokinetics and imaging characteristics of the 111In-labeled LTB4 antagonist DPC11870 were studied in New Zealand White rabbits with experimental pulmonary aspergillosis infection. The imaging characteristics of 111In-DPC11870 were compared with those of 67Ga-citrate, a radiopharmaceutical commonly used to detect pulmonary infections in patients.

METHODS:

Pulmonary aspergillosis was induced in the left lung of rabbits by intratracheal inoculation of 1 x 10(8) conidia of Aspergillus fumigatus. Three days after the inoculation, the rabbits received 111In-DPC11870 or 67Ga-citrate intravenously. Images were acquired at several time points up to 24 h after injection.

RESULTS:

Pulmonary aspergillosis was visualized with both agents. Images acquired after injection of 111In-DPC11870 showed uptake in the pulmonary lesions from 6 h after injection. Because of accumulation at the site of infection and clearance from the background, the images improved with time. Region-of-interest analysis at 24 h after injection revealed infected lung-to-normal lung ratios of 5.0 +/- 1.5 for 111In-DPC11870 and 2.9 +/- 0.6 for 67Ga-citrate.

CONCLUSION:

The radiolabeled LTB4 antagonist DPC11870 clearly delineated experimentally induced pulmonary aspergillosis in rabbits. Images acquired at 24 h after injection of 111In-DPC11870 were superior to those obtained after injection of 67Ga-citrate.

• Authors: Julliëtte E M van Eerd, Huub J J M Rennen, Wim J G Oyen, Thomas D Harris, D Scott Edwards, Frans H M Corstens, Otto C Boerman
• Journal: Journal of nuclear medicine : official publication, Society of Nuclear Medicine (J Nucl Med) Vol. 45 Issue 10 Pg. 1747-53 (Oct 2004) ISSN: 0161-5505 [Print] United States
• PMID: 15471844 (Publication Type: Comparative Study, Evaluation Study, Journal Article, Validation Study)

Chemical References

• Biphenyl Compounds
• Citrates
• DPC11870-11
• Indium Radioisotopes
• Oligopeptides
• Pyridines
• Radiopharmaceuticals
• Tetrazoles
• Leukotriene B4
• Gallium
• gallium citrate

Topics

• Animals
• Aspergillosis (diagnostic imaging, metabolism)
• Biphenyl Compounds (pharmacokinetics)
• Citrates (pharmacokinetics)
• Female
• Gallium (pharmacokinetics)
• Indium Radioisotopes (pharmacokinetics)
• Leukotriene B4 (antagonists & inhibitors, metabolism)
• Lung Diseases, Fungal (diagnostic imaging, metabolism)
• Metabolic Clearance Rate
• Oligopeptides (pharmacokinetics)
• Organ Specificity
• Pyridines (pharmacokinetics)
• Rabbits
• Radionuclide Imaging
• Radiopharmaceuticals (pharmacokinetics)
• Reproducibility of Results
• Sensitivity and Specificity
• Tetrazoles (pharmacokinetics)
• Tissue Distribution