Related Experiment Video
Updated: Jan 12, 2026
Detection of Inflammasome Activation and Pyroptotic Cell Death in Murine Bone Marrow-derived Macrophages
Published on: May 21, 2018
Bone marrow mesenchymal stem cell exosome-derived miR-223 regulated cellular pyroptosis of macrophage in
Ting Zhou1,2,3, Jie Zhu1, Feng Shan1
1Children's hospital of Soochow University, Suzhou, Jiangsu Province, China.
Abstract:
Osteomyelitis (OM) is a severe bone infection characterized by inflammation and tissue damage. Macrophages play a crucial role in the inflammatory response during OM, and exosomes derived from bone marrow mesenchymal stem cells (BMSCs) have been proposed as potential therapeutic agents. Previous studies suggest that miR-223, a microRNA involved in inflammatory processes, is dysregulated in OM. This study investigates the role of BMSCs-derived exosomes carrying miR-223 in regulating macrophage pyroptosis, a form of programmed cell death triggered by inflammation. Blood samples were collected from OM patients and control subjects to assess miR-223 expression. BMSCs were treated with LPS to simulate the OM environment. Exosomes were extracted from miR-223 overexpressing BMSCs and characterized. The effects of these exosomes on macrophage survival, apoptosis, and pyroptosis were assessed through CCK-8 assays, flow cytometry, TUNEL staining, ELISA, and western blotting. The miR-223-mediated regulation of Caspase-1 and LACC1 expression was evaluated using specific inhibitors and gene expression analysis. miR-223 expression was significantly reduced in OM patients and in LPS-treated BMSCs. BMSCs-derived exosomes carrying miR-223 (miR-223 exo) enhanced macrophage viability, reduced apoptosis, and mitigated LPS-induced pyroptosis by targeting the NLRP3 inflammasome and Caspase-1 expression. Co-treatment with miR-223 inhibitors and Caspase-1 inhibitors showed that miR-223 regulated macrophage survival and inflammation through Caspase-1 modulation. Further investigation revealed that miR-223 targeted LACC1 to alleviate macrophage pyroptosis, with LACC1 overexpression reversing the protective effects of miR-223. BMSCs-derived exosomes carrying miR-223 play a protective role in OM by regulating macrophage pyroptosis and inflammation. This effect is mediated through the modulation of Caspase-1 and LACC1 expression, highlighting the potential of miR-223-based therapies for OM treatment.
Insights
Bone infection (osteomyelitis) involves inflammation. Bone marrow mesenchymal stem cell (BMSC)-derived exosomes carrying miR-223 protect against this by reducing macrophage pyroptosis via Caspase-1 and LACC1 regulation.
Area of Science:
- Biomedical research
- Cellular and Molecular Biology
- Immunology
Background:
- Osteomyelitis (OM) is a severe bone infection with significant inflammation.
- Macrophages are key players in OM-related inflammation.
- MicroRNA-223 (miR-223) is implicated in inflammatory processes and dysregulated in OM.
Purpose of the Study:
- To investigate the therapeutic potential of bone marrow mesenchymal stem cell (BMSC)-derived exosomes carrying miR-223 in osteomyelitis.
- To elucidate the role of these exosomes in regulating macrophage pyroptosis and inflammation.
Main Methods:
- Collected blood samples from OM patients and controls to measure miR-223 levels.
- Isolated and characterized exosomes from miR-223 overexpressing BMSCs.
- Assessed exosome effects on macrophage viability, apoptosis, and pyroptosis using various assays (CCK-8, flow cytometry, ELISA, Western blotting).
- Investigated miR-223's regulatory role in Caspase-1 and LACC1 expression.
Main Results:
- miR-223 expression was decreased in OM patients and LPS-treated BMSCs.
- BMSC-derived exosomes with miR-223 (miR-223 exo) improved macrophage viability, reduced apoptosis, and suppressed LPS-induced pyroptosis.
- miR-223 targeted the NLRP3 inflammasome and Caspase-1, modulating macrophage inflammation.
- miR-223 regulated macrophage survival and inflammation via Caspase-1, and targeted LACC1 to alleviate pyroptosis.
Conclusions:
- BMSC-derived exosomes carrying miR-223 exert a protective effect in osteomyelitis.
- This protection is achieved by regulating macrophage pyroptosis and inflammation through Caspase-1 and LACC1 pathways.
- miR-223-loaded exosomes represent a promising therapeutic strategy for osteomyelitis treatment.
