Cobalt-doped Ti surface promotes immunomodulation

Area of Science:

• Biomaterials Science
• Materials Engineering
• Immunology

Background:

• Titanium (Ti) implants are widely used in orthopedics and dentistry.
• Enhancing implant biocompatibility and reducing post-operative inflammation are critical challenges.
• Plasma electrolytic oxidation (PEO) is a surface modification technique to improve implant properties.

Purpose of the Study:

• To prepare cobalt-doped PEO coatings on Ti implants.
• To investigate the biocompatibility, cell adhesion, and immunomodulatory effects of these coatings.
• To evaluate the anti-inflammatory potential of cobalt-loaded Ti implants in vitro and in vivo.

Main Methods:

• Fabrication of cobalt-doped PEO coatings on Ti substrates with varying cobalt concentrations.
• In vitro assessment of ion release, biocompatibility, and cell adhesion.
• In vitro enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (PCR) to analyze macrophage responses (M1/M2 polarization).
• In vivo air pouch model to evaluate the anti-inflammatory effects.

Main Results:

• Cobalt-doped PEO coatings exhibited slow and sustainable release of cobalt ions.
• Enhanced cell adhesion and biocompatibility were observed compared to pure Ti.
• Cobalt-loaded Ti demonstrated immunomodulatory effects on macrophages, upregulating anti-inflammatory (M1) genes and downregulating pro-inflammatory (M2) genes.
• High cobalt content promoted M2 macrophage polarization.
• In vivo studies indicated that cobalt-loaded Ti mitigated inflammatory reactions.

Conclusions:

• Cobalt-doped PEO coatings represent a promising surface modification for Ti implants.
• These coatings enhance biocompatibility and possess significant immunomodulatory and anti-inflammatory properties.
• The findings suggest a novel strategy for developing advanced implant materials with improved clinical outcomes.