Biomaterials are becoming increasingly crucial for healthcare solutions, with extensive use in the field of tissue engineering and drug delivery. After implantation, biomaterials trigger an immune response characterized by the recruitment of bone‐marrow‐derived proinflammatory macrophages that develop as the most abundant cell type surrounding the biomaterial. Chronic activation of this recruited macrophage population induces a foreign body reaction response and consequent biomaterial rejection. However, transition toward a proreparative phenotype is associated with biomaterial integration and tissue homeostasis restoration. In this review, the most relevant strategies that modulate biomaterial immune response are discussed, including mechanical properties, surface coatings, release of anti‐inflammatory molecules and cytokines, antibacterial features, origin and inner moieties of biomaterials, and cell crosstalk. Moreover, the role of tissue resident macrophages, an embryo‐derived macrophage population with a strong reparative potential, in promoting biomaterial tolerance will be reviewed. This provides new insights to better tune the reaction of the host immune system to implanted biomaterials in order to favor integration and increase the knowledge of macrophages as key players in tissue homeostasis.
While inflammation can be problematic, it is nonetheless necessary for proper tissue regeneration. However, it remains unclear how the magnitude and duration of the inflammatory response impacts regenerative outcome. This is partially due to the difficulty in temporally regulating macrophage phenotype at wound sites. Here, a magnetically responsive biomaterial system potentially capable of temporally regulating macrophage phenotypes through sequential, on‐demand cytokine deliveries is presented. This material system is designed to (i) rapidly recruit proinflammatory macrophages (M1) through initial cytokine deliveries and (ii) subsequently transition macrophages toward anti‐inflammatory phenotypes (M2s) through delayed, magnetically triggered cytokine release. Here, the ability of this system to initially deliver proinflammatory cytokines (i.e., monocyte chemoattractant protein‐1 and interferon gamma), recruit, and harbor an expanding macrophage population, and delay deliveries of anti‐inflammatory cytokines (i.e., IL‐4 and IL‐10) until the application of magnetic fields from simple hand‐held magnets is demonstrated. Critically, the timing and rate of these delayed deliveries can be remotely/magnetically controlled. This biomaterial system can provide a powerful tool in (i) understanding the relationship between inflammation and regenerative outcome, (ii) developing optimized cytokine delivery strategies, and (iii) clinically implementing those optimized delivery strategies with the on‐demand versatility needed to alter the course of therapies in real time.
more » « less- PAR ID:
- 10056673
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- Volume:
- 7
- Issue:
- 12
- ISSN:
- 2192-2640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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