Osteoimmunomodulatory Nanoparticles for Bone Regeneration

Abstract

Treatment of large bone fractures remains a challenge for orthopedists. Bone regeneration is a complex process that includes skeletal cells such as osteoblasts, osteoclasts, and immune cells to regulate bone formation and resorption. Osteoimmunology, studying this complicated process, has recently been used to develop biomaterials for advanced bone regeneration. Ideally, a biomaterial shall enable a timely switch from early stage inflammatory (to recruit osteogenic progenitor cells) to later-stage anti-inflammatory (to promote differentiation and terminal osteogenic mineralization and model the microstructure of bone tissue) in immune cells, especially the M1-to-M2 phenotype switch in macrophage populations, for bone regeneration. Nanoparticle (NP)-based advanced drug delivery systems can enable the controlled release of therapeutic reagents and the delivery of therapeutics into specific cell types, thereby benefiting bone regeneration through osteoimmunomodulation. In this review, we briefly describe the significance of osteoimmunology in bone regeneration, the advancement of NP-based approaches for bone regeneration, and the application of NPs in macrophage-targeting drug delivery for advanced osteoimmunomodulation.

Review of recent progress in the development of electrolytes for Cd/Pb-based quantum dot-sensitized solar cells: performance and stability

“…In addition they have high ion conductivity, therefore they are ideal solid electrolytes for QDSSCs. 92 Moreover perovskite materials can be used in conjunction with other components of the devices, such as counter electrodes and photoanodes. 93 The synthesis method can affect the optical properties of perovskite-based solid-state electrolytes.…”

Two‐dimensional materials for bone‐tissue engineering

“…Bone is an essential organ in human bodies because not only provides structural support, load-bearing for moving, and physical protection of the interior organs but also serves as a foundation for hematopoiesis and tissue regeneration because the bone marrow contains a large number of hematopoietic stem cells and bone marrow-derived mesenchymal stem cells (BMSCs) that can differentiate into different types of blood cells and osteocytes. 7,8,9 Bone is made up of living bone cells organized in a biomineral media based on calcium phosphate (CaP). 10 Bone is made up of a variety of cell types, such as osteocytes, osteoblasts, and osteoclasts that are all entrenched in an intricate microenvironment.…”

“…Bone is an essential organ in human bodies because not only provides structural support, load‐bearing for moving, and physical protection of the interior organs but also serves as a foundation for hematopoiesis and tissue regeneration because the bone marrow contains a large number of hematopoietic stem cells and bone marrow‐derived mesenchymal stem cells (BMSCs) that can differentiate into different types of blood cells and osteocytes 7,8,9 …”

Harnessing osteoimmunity to treat peri-implant inflammatory osteolysis

“…It is essential to modulate the host's immune microenvironment in response to the biomaterial and harness it toward an ideal, favorable, and stable bone microenvironment, which is also called ''osteoimmunomodulation'' of bone regeneration. 15 Bioactive materials such as polymers, ceramics, metals, monolithic architected composites, microporous nanoparticles, fibrous hydrogel networks, and 3D printed scaffolds directly recruit endogenous immune cells and stem cells for tissue healing and regeneration. 16 In addition, bioactive materials that mediate bioelectricity also have a modulating effect on osteoimmunity due to the active bioelectrical properties of the bone tissue, such as the piezoelectric, pyroelectric, and ferroelectric charges mediated by collagen fibrils as well as the electro-osmosis and streaming potential present in bone tubules and laminae.…”