Diatom-Based Artificial Antigen-Presenting Cells: A Novel Approach for Adaptive Immune Modulation.

Area of Science:

• Biomaterials Science
• Immunology
• Nanotechnology

Background:

• Artificial antigen-presenting cells (aAPCs) are crucial for immunotherapy, but challenges like unintended effects persist.
• Diatoms offer unique surface properties suitable for biomaterial development, mimicking cellular structures.

Purpose of the Study:

• To create calcium-modified diatoms as functional artificial antigen-presenting cells (aAPCs).
• To enhance immunological interactions and replicate natural antigen-presenting cell functions.

Main Methods:

• Calcium modification of diatoms followed by amine polymerization.
• Immobilization of immunomodulatory proteins (anti-CD3 and anti-CD28) onto diatom surfaces.
• Co-culture with human T cells to assess immunological synapse formation and T cell activation.

Main Results:

• Amine polymerization enhanced protein attachment, promoting T cell-specific interactions and immunological synapse formation.
• Diatom-based aAPCs induced robust expression of T cell activation markers (CD69, CD25) and increased T cell proliferation.
• Metabolic analysis revealed a shift towards glycolysis to support T cell activation energy demands.

Conclusions:

• Immunofunctionalization of calcium-modified diatoms provides a viable strategy for bioinspired aAPCs.
• These functional aAPCs represent adaptive immunomodulatory systems with potential in cancer and autoimmunity immunotherapy.