Tumor‐associated macrophages (TAMs) are a complex and heterogeneous population of cells within the tumor microenvironment. In many tumor types, TAMs contribute toward tumor malignancy and are therefore a therapeutic target of interest. Here, three major strategies for regulating TAMs are highlighted, emphasizing the role of biomaterials in these approaches. First, systemic methods for targeting tumor‐associated macrophage are summarized and limitations to both passive and active targeting approaches considered. Second, lessons learned from the significant literature on wound healing and macrophage response to implanted biomaterials are discussed with the vision of applying these principles to localized, biomaterial‐based modulation of tumor‐associated macrophage. Finally, the developing field of engineered macrophages, including genetic engineering and integration with biomaterials or drug delivery systems, is examined. Analysis of major challenges in the field along with exciting opportunities for the future of macrophage‐based therapies in oncology are included.
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.
more » « less- NSF-PAR ID:
- 10376235
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 30
- Issue:
- 44
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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