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In Situ Sustained Macrophage-Targeted Nanomicelle-Hydrogel Microspheres for Inhibiting Osteoarthritis
XiaoXiao Li1, Xingchen Li1, Jielai Yang1
1Department of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, Shanghai 200025, P. R. China.
Abstract:
There are still challenges in applying drug nanocarriers for in situ sustained macrophage targeting and regulation, due to the rapid clearance of nanocarriers and burst drug release in vivo. Herein, a nanomicelle-hydrogel microsphere, characterized by its macrophage-targeted nanosized secondary structure that allows it to accurately bind to M1 macrophages through active endocytosis, is employed for in situ sustained macrophage targeting and regulation, and addresses the insufficient osteoarthritis therapeutic efficacy caused by rapid clearance of drug nanocarriers. The 3-dimensional structure of a microsphere can prevent the rapid escape and clearance of a nanomicelle, thus keeping it in joints, while the ligand-guided secondary structure can carry drugs to accurately target and enter M1 macrophages, and release drugs via the transition from hydrophobicity to hydrophilicity of nanomicelles under inflammatory stimulation inside the macrophages. The experiments show that the nanomicelle-hydrogel microsphere can in situ sustainably target and regulate M1 macrophages for more than 14 days in joints, and attenuate local "cytokine storm" by continuous M1 macrophage apoptosis promotion and polarization inhibition. This micro/nano-hydrogel system shows excellent ability to sustainably target and regulate macrophage, realizes the improvement of drug utilization and efficacy inside the macrophage, and thereby can be a potential platform for treating macrophage-related diseases.
Insights
New micro/nano-hydrogel microspheres effectively target M1 macrophages in joints for over 14 days. This sustained drug delivery system improves osteoarthritis treatment by regulating macrophage activity and reducing inflammation.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Immunology
Background:
- Drug nanocarriers face challenges like rapid clearance and burst release, limiting in situ sustained targeting and regulation of macrophages.
- Osteoarthritis treatment efficacy is often insufficient due to these limitations in drug delivery systems.
Purpose of the Study:
- To develop a nanomicelle-hydrogel microsphere for in situ sustained macrophage targeting and regulation.
- To address the limitations of current nanocarriers for improved osteoarthritis therapy.
Main Methods:
- Fabrication of a micro/nano-hydrogel system with macrophage-targeted nanosized secondary structures.
- Utilizing the microsphere's 3D structure to prevent nanomicelle escape and clearance.
- Employing ligand-guided targeting for M1 macrophage entry and intracellular drug release triggered by inflammatory stimuli.
Main Results:
- The nanomicelle-hydrogel microsphere achieved sustained in situ targeting and regulation of M1 macrophages for over 14 days in joints.
- The system effectively attenuated local "cytokine storm" by promoting M1 macrophage apoptosis and inhibiting polarization.
- Demonstrated improved drug utilization and efficacy within macrophages.
Conclusions:
- The developed micro/nano-hydrogel system shows significant potential for sustained macrophage targeting and regulation.
- This platform offers improved drug delivery and efficacy for treating macrophage-related diseases, including osteoarthritis.
- The system provides a promising approach for managing inflammatory conditions driven by macrophage activity.
