Multiscale Hybrid Surface Topographies Orchestrate Immune Regulation, Antibacterial Defense, and Tissue Regeneration

Area of Science:

• Biomaterials Science
• Surface Engineering
• Regenerative Medicine

Background:

• Implant complications like infection and poor integration necessitate advanced solutions beyond current chemical strategies.
• Existing surface topographies often fail to address the complex multicellular interactions at the implant-host interface.

Purpose of the Study:

• To develop a multifunctional platform using nano-micro hybrid wrinkled topographies for simultaneous modulation of bacteria, immune cells, and tissue progenitors.
• To evaluate the platform's efficacy in reducing bacterial adhesion, regulating immune responses, and promoting tissue regeneration.

Main Methods:

• Fabrication of nano-micro hybrid wrinkled topographies using layer-by-layer (LbL) self-assembly and mechanical nanomanufacturing.
• Assessment of bacterial adhesion and biofilm formation on the hybrid surfaces.
• Evaluation of macrophage polarization and osteogenic differentiation in response to the surface topography.

Main Results:

• Nanoscale features significantly reduced bacterial adhesion and biofilm formation (>50% reduction).
• Microscale features enhanced macrophage M2 polarization (≈3-fold increase) and osteogenic differentiation (>8-fold increase in ALP activity).
• Macrophages demonstrated context-dependent behavior, balancing inflammation and repair for improved implant integration.

Conclusions:

• The developed nano-micro hybrid surface topography offers a multifunctional approach to address key challenges in implant biomaterials.
• This platform enables antibacterial activity, immune regulation, and enhanced tissue regeneration, paving the way for next-generation implantable devices.
• The modular design allows for broad applicability across different cell types and disease contexts.