Precision treatment of viral pneumonia through macrophage-targeted lipid nanoparticle delivery
Gan Zhao1,2,3, Lulu Xue4, Hannah C Geisler4
1Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104.
Abstract:
Macrophages are integral components of the innate immune system, playing a dual role in host defense during infection and pathophysiological states. Macrophages contribute to immune responses and aid in combatting various infections, yet their production of abundant proinflammatory cytokines can lead to uncontrolled inflammation and worsened tissue damage. Therefore, reducing macrophage-derived proinflammatory cytokine release represents a promising approach for treating various acute and chronic inflammatory disorders. However, limited macrophage-specific delivery vehicles have hindered the development of macrophage-targeted therapies. In this study, we screened a pool of 112 lipid nanoparticles (LNPs) to identify an optimal LNP formulation for efficient siRNA delivery. Subsequently, by conjugating the macrophage-specific antibody F4/80 to the LNP surface, we constructed MacLNP, an enhanced LNP formulation designed for targeted macrophage delivery. In both in vitro and in vivo experiments, MacLNP demonstrated a significant enhancement in targeting macrophages. Specifically, delivery of siRNA targeting TAK1, a critical kinase upstream of multiple inflammatory pathways, effectively suppressed the phosphorylation/activation of NF-kB. LNP-mediated inhibition of NF-kB, a key upstream regulator in the classic inflammatory signaling pathway, in the murine macrophage cell line RAW264.7 significantly reduced the release of proinflammatory cytokines after stimulation with the viral RNA mimic Poly(I:C). Finally, intranasal administration of MacLNP-encapsulated TAK1 siRNA markedly ameliorated lung injury induced by influenza infection. In conclusion, our findings validate the potential of targeted macrophage interventions in attenuating inflammatory responses, reinforcing the potential of LNP-mediated macrophage targeting to treat pulmonary inflammatory disorders.
Insights
Targeted lipid nanoparticles (LNPs) effectively deliver siRNA to macrophages, reducing inflammatory cytokine release and ameliorating lung injury in influenza infection models. This approach shows promise for treating inflammatory disorders.
Area of Science:
- Immunology
- Nanotechnology
- Molecular Biology
Background:
- Macrophages play a critical role in innate immunity but can exacerbate inflammation.
- Uncontrolled inflammation driven by macrophages contributes to various diseases.
- Targeted therapies are needed to modulate macrophage activity effectively.
Purpose of the Study:
- To develop and evaluate macrophage-specific lipid nanoparticles (LNPs) for targeted siRNA delivery.
- To assess the efficacy of these targeted LNPs in suppressing inflammatory pathways.
- To investigate the therapeutic potential in a murine model of lung injury.
Main Methods:
- Screening of 112 lipid nanoparticles (LNPs) for optimal siRNA delivery.
- Conjugation of the F4/80 antibody to LNPs to create macrophage-targeted MacLNPs.
- In vitro studies using RAW264.7 cells to assess NF-kB inhibition and cytokine release.
- In vivo studies involving intranasal administration of MacLNP-encapsulated TAK1 siRNA in a murine influenza infection model.
Main Results:
- MacLNP demonstrated enhanced targeting of macrophages in vitro and in vivo.
- siRNA targeting TAK1 via MacLNP effectively suppressed NF-kB activation.
- Inhibition of NF-kB significantly reduced proinflammatory cytokine release in macrophages.
- Intranasal MacLNP delivery of TAK1 siRNA ameliorated influenza-induced lung injury.
Conclusions:
- Targeted macrophage intervention using MacLNP is a viable strategy to attenuate inflammatory responses.
- Lipid nanoparticle-mediated macrophage targeting holds potential for treating pulmonary inflammatory disorders.
- This study validates MacLNP as an effective platform for macrophage-specific therapeutic delivery.
