Drug Development

Area of Science:

• Neuroscience
• Immunology
• Biotechnology

Background:

• Programmed death ligand 1 (PD-L1) dysregulation contributes to neuroinflammation and impaired amyloid-beta (Aβ) clearance in Alzheimer's disease (AD).
• Upregulated PD-L1 in AD brains hinders microglial function, exacerbating disease pathology.

Purpose of the Study:

• To develop a brain-targeted system for regulating PD-L1 in the central nervous system (CNS).
• To investigate the therapeutic potential of this system in an AD mouse model.

Main Methods:

• Development of a brain-targeted Nano-ERASER system (BTN-PDL1) to target PD-L1.
• Assessment of BTN-PDL1's ability to cross the blood-brain barrier (BBB).
• Evaluation of PD-L1 depletion via Trim21-mediated proteasomal degradation in microglia and astrocytes.

Main Results:

• BTN-PDL1 successfully crossed the BBB and depleted PD-L1, restoring microglial and astrocyte functions.
• Treatment with BTN-PDL1 led to clearance of toxic Aβ fibrils and reduced neuroinflammation.
• Animal behavior assays demonstrated that BTN-PDL1 halted AD progression and improved cognitive function in 5XFAD mice.

Conclusions:

• The BTN-PDL1 system offers a novel strategy for treating AD by modulating PD-L1.
• This approach holds potential for treating various CNS diseases characterized by protein malfunction and neuroinflammation, including Parkinson's disease, Huntington's disease, ALS, stroke, and TBI.