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Updated: Jul 19, 2025
Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring
Published on: December 9, 2010
A Ratiometric SERS Probe for Imaging the Macrophage Phenotypes in Live Mice with Epilepsy and Brain Tumor
Wenjia Duan1,2, Cong Wang1,3, Yiqing Jiang1
1Key Laboratory of Smart Drug Delivery, Ministry of Education; Innovative Center for New Drug Development of Immune Inflammatory Diseases, Ministry of Education, School of Pharmacy, Fudan University, Shanghai, 201203, China.
Abstract:
Macrophage performs multiple functions such as pathogen phagocytosis, antigen presentation, and tissue remodeling by polarizing toward a spectrum of phenotypes. Dynamic imaging of macrophage phenotypes is critical for evaluating disease progression and the therapeutic response of drug candidates. However, current technologies cannot identify macrophage phenotypes in vivo. Herein, a surface-enhanced Raman scattering nanoprobe, AH1, which enables the accurate determination of physiological pH with high sensitivity and tissue penetration depth through ratiometric Raman signals is developed. Due to the phenotype-dependent metabolic reprogramming, AH1 can effectively identify macrophage subpopulations by measuring the acidity levels in phagosomes. After intravenous administration, AH1 not only visualizes the spatial distribution of macrophage phenotypes in brain tumors and epileptic regions of mouse models, but also reveals the repolarization of macrophages in brain lesions after drug intervention. This work provides a new tool for dynamically monitoring the disease-associated immune microenvironment and evaluating the efficacy of immune-therapeutics in vivo.
Insights
Researchers developed a novel nanoprobe (AH1) to visualize macrophage phenotypes in vivo. This tool tracks immune cell changes in diseases and after drug treatment, aiding therapeutic evaluation.
Area of Science:
- Immunology
- Nanotechnology
- Biomedical Imaging
Background:
- Macrophages exhibit diverse phenotypes crucial for immune responses and tissue homeostasis.
- Dynamic monitoring of macrophage phenotypes in vivo is essential for understanding disease progression and therapeutic efficacy.
- Current in vivo imaging technologies lack the capability to differentiate macrophage phenotypes.
Purpose of the Study:
- To develop a novel nanoprobe for in vivo identification and dynamic imaging of macrophage phenotypes.
- To assess the utility of the nanoprobe in disease models and in response to drug intervention.
Main Methods:
- Development of a surface-enhanced Raman scattering (SERS) nanoprobe (AH1) for sensitive and accurate physiological pH determination.
- Utilizing ratiometric Raman signals for pH measurement, enabling high tissue penetration depth.
- Leveraging phenotype-dependent metabolic reprogramming and phagosomal acidity for macrophage subpopulation identification.
Main Results:
- The AH1 nanoprobe accurately determined physiological pH with high sensitivity and tissue penetration.
- AH1 effectively identified macrophage subpopulations based on phagosomal acidity levels.
- In vivo imaging revealed the spatial distribution of macrophage phenotypes in brain tumors and epileptic regions.
- The nanoprobe visualized macrophage repolarization in brain lesions following drug intervention.
Conclusions:
- The developed AH1 nanoprobe offers a new tool for dynamic in vivo monitoring of the disease-associated immune microenvironment.
- This technology enables effective evaluation of immune-therapeutic efficacy in vivo.
- AH1 facilitates a deeper understanding of macrophage dynamics in pathological conditions and treatment responses.
