Phosphatidylserine-mediated oral tolerance

Area of Science:

• Immunology
• Biochemistry
• Nanotechnology

Background:

• Phosphatidylserine (PS) is an anionic phospholipid on apoptotic cells, crucial for immune tolerance.
• PS exposure typically signals phagocytes for silent cell clearance, maintaining immunological ignorance.
• Emerging evidence shows PS actively promotes a tolerogenic environment, converting immunogens into tolerogens.

Purpose of the Study:

• To leverage PS-mediated immune regulation for developing an effective oral tolerance immunotherapy.
• To investigate the role of PS density and biophysical characteristics in engaging tolerogenic receptors like TIM-4.

Main Methods:

• Harnessing cellular and molecular mechanisms of PS-mediated immune regulation.
• Designing and utilizing PS-based nanoparticles for oral administration.
• Assessing the engagement of tolerogenic receptors (e.g., TIM-4) on antigen-presenting cells.

Main Results:

• PS exposure on cells/vesicles actively promotes a tolerogenic environment.
• PS density on vesicles is critical for engaging tolerogenic receptors like TIM-4.
• PS-based oral immunotherapy demonstrated efficacy in preventing/reducing immune responses against various antigens.

Conclusions:

• PS-based nanoparticles represent a novel and effective oral tolerance immunotherapy.
• This approach shows broad potential clinical applications, including protein therapies, food allergens, autoantigens, and gene therapy vectors.
• The favorable safety profile and ease of administration of PS enhance its therapeutic promise.