Advancing bone repair through immunoengineering: current strategies and future directions

Osteogenesis and bone tissue regeneration represent complex physiological processes characterized by the orchestrated interactions between immune cells, signaling molecules, and osteoprogenitor lineages. Recent advances in immunoengineering offer innovative approaches for modulating the immune microenvironment, thereby optimizing desired regenerative outcomes in bone repair. Dysregulated immune responses, often precipitated by trauma, senescence, or pathological conditions, create inflammatory environments that can inhibit osteogenesis. This review focuses on emerging strategies in immunoengineering designed to adjust immune responses, augment osteoinductive potential, and facilitate bone tissue regeneration. Key methodologies include the functional application of biomaterial scaffolds to modulate immune cell recruitment and polarization, optimization of cytokine and chemokine delivery systems tailored for controlled release kinetics, and establishment of a pro-regenerative niche with balanced pro- and anti-inflammatory cues through scaffold engineering. Innovative methods range from immune cell reprogramming to adoptive immunotherapy, both concentrating on their capacities to modulate immune dynamics in alignment with the temporal phases of bone regeneration. By integrating principles from immunology and regenerative biology, immunoengineering offers a robust framework for advancing osteogenic strategies and holds significant translational potential for clinical applications in skeletal tissue regeneration. This review discusses in detail key immunoengineering strategies, charting a course for future advancements in osteogenic regenerative therapies.