Stealth Immune Properties of Graphene Oxide Enabled by Surface-Bound Complement Factor H.

Area of Science:

• Biomaterials Science
• Immunology
• Nanotechnology

Background:

• Nanomaterials can trigger adverse innate immune responses, particularly complement activation.
• Current methods like polymer coatings offer only moderate protection against complement activation.

Purpose of the Study:

• To investigate noncovalent protein adsorption strategies for mitigating complement activation on graphene-based nanomaterials.
• To evaluate the efficacy of different proteins in creating a "stealth effect" for nanomaterials.

Main Methods:

• Graphene-based nanomaterials were precoated with purified proteins: complement factor H, bovine serum albumin, human serum albumin, and immunoglobulin G.
• Complement activation levels were measured after protein precoating.

Main Results:

• Coating with complement factor H achieved nearly complete protection (>90% reduction) against complement activation.
• Bovine or human serum albumin provided moderate protection (∼40% reduction).
• Immunoglobulin G amplified complement activation.

Conclusions:

• Surface-bound factor H and serum albumins can effectively prevent graphene oxide-triggered complement activation.
• Noncovalent protein precoating offers a facile, biomimetic approach to achieve "stealth" nanomaterials by inhibiting complement activation to natural levels.