In Vivo MRI of Functionalized Iron Oxide Nanoparticles for Brain Inflammation.
Tang TangAnthony ValenzuelaFanny PetitSarah ChowKevin LeungFredric GorinAngelique Y LouieMarc DhenainPublished in: Contrast media & molecular imaging (2018)
Microglia are intrinsic components of the brain immune system and are activated in many central nervous system disorders. The ability to noninvasively image these cells would provide valuable information for both research and clinical applications. Today, most imaging probes for activated microglia are mainly designed for positron emission tomography (PET) and target translocator proteins that also reside on other cerebral cells. The PET images obtained are not specific for microglia-driven inflammation. Here, we describe a potential PET/MRI multimodal imaging probe that selectively targets the scavenger receptor class A (SR-A) expressed on activated microglia. These sulfated dextran-coated iron oxide (SDIO) nanoparticles are avidly taken up by microglia and appear to be nontoxic when administered intravenously in a mouse model. Intravenous administration of this SDIO demonstrated visualization by T2∗ -weighted MRI of microglia activated by intracerebral administration of tumor necrosis factor alpha (TNF-α). The contrast was significantly enhanced by SDIO, whereas there was little to no contrast change in animals treated with nontargeted nanoparticles or untreated controls. Thus, SR-A targeting represents a promising strategy to image activated microglia in the brain.
Keyphrases
- positron emission tomography
- inflammatory response
- contrast enhanced
- computed tomography
- neuropathic pain
- magnetic resonance imaging
- pet ct
- induced apoptosis
- mouse model
- oxidative stress
- magnetic resonance
- pet imaging
- white matter
- deep learning
- high resolution
- rheumatoid arthritis
- cerebral ischemia
- resting state
- diffusion weighted imaging
- spinal cord
- multiple sclerosis
- cell cycle arrest
- quantum dots
- iron oxide nanoparticles
- spinal cord injury
- endoplasmic reticulum stress
- high dose
- iron oxide
- small molecule
- optical coherence tomography
- risk assessment
- signaling pathway
- subarachnoid hemorrhage
- functional connectivity
- chronic pain
- healthcare
- cancer therapy
- pain management
- cell death
- fluorescence imaging
- blood brain barrier
- climate change
- drug delivery
- health information
- walled carbon nanotubes
- brain injury