Near-Infrared Switch-Driven Macrophage Dynamically Reprogramming for Anti-Infection and Tissue Healing on Polyetheretherketone Implants.

High infection risk and poor tissue integration are major causes of percutaneous implant failure. Immune reprogramming is a promising strategy, but current implants rely predominantly on passive and static modulation of macrophages. Dynamically reprogramming macrophages based on physiological states to switch between antibacterial and tissue-healing functions remains a challenge. Here, a novel polyetheretherketone (PEEK) surface is developed sequentially modified through sulfonation, hydrogen plasma immersion ion implantation (H-PIII), and magnesium plasma immersion ion implantation (Mg-PIII) to fabricate a Mg-H-SPEEK composite with a graphene-like matrix embedded with MgO. This film simultaneously enables sustained Mg2⁺ release with near-infrared (NIR) photothermal responsiveness for on-demand immunomodulation. Under normal conditions, Mg2⁺ released from Mg-H-SPEEK can promote macrophage reprogramming toward the M2 phenotype through the TNF, JAK-STAT, NF-κB, and IL-17 pathways to accelerate soft tissue repair. Upon NIR light exposure, photothermal stimulation enhances the expression of the Traf1 in macrophages via the TNF, FoxO, and JAK-STAT signaling pathways to drive M1 reprogramming for bacterial phagocytosis. The dual-mode system synergizes hyperthermia and immune phagocytosis for infection resistance while preserving pro-healing functions, offering a smart strategy for percutaneous implants.