CX3CR1: a potential microglia-specific PET imaging target in Alzheimer's and Parkinson's diseases

Hongzhi Yang1, Yanli Wang2, Yulong Xu2

  • 1Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States.

Frontiers in Pharmacology
|December 22, 2025
PubMed

Insights

Microglia

Area of Science:

  • Neuroimmunology
  • Central Nervous System (CNS) research
  • Microglial biology

Background:

  • Microglia are key CNS immune cells regulating brain homeostasis.
  • CX3CR1 receptor on microglia interacts with CX3CL1, influencing neuroimmune responses.
  • CX3CR1-CX3CL1 signaling has complex, context-dependent roles in neurodegenerative diseases like Alzheimer's and Parkinson's.

Purpose of the Study:

  • To highlight the complex and incompletely understood role of CX3CR1 in microglial dynamics.
  • To emphasize the need for novel Positron Emission Tomography (PET) tracers targeting CX3CR1.
  • To explore opportunities for diagnosing and treating neuroinflammation-associated neurodegenerative diseases.

Main Methods:

  • Review of existing literature on CX3CR1 function in neurodegeneration models.
  • Discussion of the potential of Positron Emission Tomography (PET) for in vivo imaging of microglial CX3CR1.
  • Identification of the need for developing and validating new PET tracers.

Main Results:

  • CX3CR1 deficiency yields paradoxical outcomes in Alzheimer's and Parkinson's disease models.
  • CX3CR1 is a promising, yet complex, therapeutic and diagnostic target.
  • PET imaging offers a noninvasive approach to study in vivo microglial CX3CR1 dynamics.

Conclusions:

  • Developing novel PET tracers for microglial CX3CR1 is crucial.
  • Such tracers could advance diagnosis and treatment strategies for neuroinflammatory diseases.
  • Further research into CX3CR1's role is essential for understanding and combating neurodegeneration.