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Updated: Jul 11, 2026
Using Luciferase to Image Bacterial Infections in Mice
Published on: February 18, 2011
Optical imaging of bacterial infection in living mice using a fluorescent near-infrared molecular probe
W Matthew Leevy1, Seth T Gammon, Hua Jiang
1Department of Chemistry and Biochemistry, 251 Nieuwland Science Hall, University of Notre Dame, Notre Dame, IN 46556, USA.
Abstract:
An optical imaging probe was synthesized by attaching a near-infrared carbocyanine fluorophore to an affinity group containing two zinc(II) dipicolylamine (Zn-DPA) units. The probe has a strong and selective affinity for the surfaces of bacteria, and it was used to image infections of Gram-positive S. aureus and Gram-negative E. coli bacteria in living nude mice. After intravenous injection, the probe selectively accumulates at the sites of localized bacterial infections in the thigh muscles of the mice.
Insights
A novel optical imaging probe targets bacterial surfaces, enabling selective visualization of Gram-positive and Gram-negative infections in mice. This advancement aids in precisely locating bacterial infections for potential therapeutic interventions.
Area of Science:
- Biomedical Imaging
- Infectious Disease Research
- Nanotechnology
Background:
- Bacterial infections pose a significant global health challenge.
- Accurate and early detection of bacterial infections is crucial for effective treatment.
- Current imaging techniques may lack specificity for bacterial targets.
Purpose of the Study:
- To develop and evaluate a novel optical imaging probe for bacterial infections.
- To assess the probe's affinity and selectivity for bacterial surfaces.
- To demonstrate the probe's efficacy in visualizing bacterial infections in vivo.
Main Methods:
- Synthesis of an optical imaging probe by conjugating a near-infrared carbocyanine fluorophore to a zinc(II) dipicolylamine (Zn-DPA) affinity group.
- In vitro assessment of probe affinity and selectivity for bacterial surfaces.
- In vivo imaging studies in living nude mice with localized Gram-positive (S. aureus) and Gram-negative (E. coli) bacterial infections.
Main Results:
- The synthesized probe exhibited strong and selective binding to bacterial surfaces.
- The probe successfully visualized localized S. aureus and E. coli infections in the thigh muscles of mice.
- Intravenous injection led to selective accumulation of the probe at infection sites, demonstrating in vivo targeting capability.
Conclusions:
- The developed optical imaging probe shows promise for targeted bacterial infection detection.
- The probe's ability to selectively image both Gram-positive and Gram-negative bacteria in vivo is a significant advancement.
- This technology could potentially improve the diagnosis and management of bacterial infections.
