Biomaterial scaffolds regulate macrophage activity to accelerate bone regeneration

Abstract

Bones are important for maintaining motor function and providing support for internal organs. Bone diseases can impose a heavy burden on individuals and society. Although bone has a certain ability to repair itself, it is often difficult to repair itself alone when faced with critical-sized defects, such as severe trauma, surgery, or tumors. There is still a heavy reliance on metal implants and autologous or allogeneic bone grafts for bone defects that are difficult to self-heal. However, these grafts still have problems that are difficult to circumvent, such as metal implants that may require secondary surgical removal, lack of bone graft donors, and immune rejection. The rapid advance in tissue engineering and a better comprehension of the physiological mechanisms of bone regeneration have led to a new focus on promoting endogenous bone self-regeneration through the use of biomaterials as the medium. Although bone regeneration involves a variety of cells and signaling factors, and these complex signaling pathways and mechanisms of interaction have not been fully understood, macrophages undoubtedly play an essential role in bone regeneration. This review summarizes the design strategies that need to be considered for biomaterials to regulate macrophage function in bone regeneration. Subsequently, this review provides an overview of therapeutic strategies for biomaterials to intervene in all stages of bone regeneration by regulating macrophages.

A sequential macrophage activation strategy for bone regeneration: A micro/nano strontium-releasing composite scaffold loaded with lipopolysaccharide

“…Macrophage polarization can be influenced by the chemical composition and physical properties of the scaffold [ 1 , 3 , 39 ]. As shown by the in vitro degradation results in Section 3.3 , the overall degradation trends of n-HA/PCL/PLGA and n-SrHA/PCL/PLGA were similar, and the difference was in the release of Sr and Ca ions.…”

Unveiling the Potential of Single‐Cell Encapsulation in Biomedical Applications: Current Advances and Future Perspectives

“…Jian Wang et al [79] AC-pulse-modulated E-jet 3D printing system Gelatin, hyaluronic acid, glycerol and alginate NIH3T3 and HCT116 Tumor spheroids production Yujie Zhang et al [82] Emulsification (water-water) Alginate MSC Bone regeneration Haoyue Zhang et al [157] Emulsification (water-water) Alginate MSC Cell encapsulation platform Liyuan Zhang et al [158] Emulsification (water-water) Alginate NIH3T3, HUVECs and MSC Cell encapsulation platform Tian kun Liu et al [86] Integration of extrusion printing and AVIFJ Alginate HeLa, HepG2, and HUVECs Construction of artificial tissues Venkatesh Selvam et al [159] Automated photopolymerization system GelMA HeLa Cell analysis Dan Liu et al [160] Emulsification (water-oil) Alginate MCF-7 Cell encapsulation platform Chuanfeng An et al [161] Emulsification (water-oil) GelMA, methacrylated hyaluronic acid, nitrobenzenefunctionalized hyaluronic acid MSC Bone regeneration required that the shell possesses the ability to disintegrate as needed in response to stimuli or through controlled degradation.…”

Modulation of macrophages by biophysical cues in health and beyond

“…How these biophysical properties influence macrophages for this have been outlined above and the reader is also referred to [ 77 ]. The biophysical properties of scaffolds are often combined with chemical modification to induce the greatest effects on healing, for example, modified traditional collagen membranes with epigallocatechin-3-gallate achieve better M2 phenotypic macrophage recruitment [ 78 ].…”