Optimization of a Liposomal DNase I Formulation with an Extended Circulating Half-Life

Physicochemical Design of Nanoparticles to Interface with and Degrade Neutrophil Extracellular Traps

Neutrophil extracellular traps (NETs) are networks of decondensed chromatin, histones, and antimicrobial proteins released by neutrophils in response to an infection. NET overproduction can cause an exacerbated hyperinflammatory response in a variety of diseases and can lead to host tissue damage without clearance of infection. Nanoparticle drug delivery is a promising avenue for creating materials that can both target NETs and deliver sustained amounts of NET-degrading drugs to alleviate hyperinflammation. Here, we study how particle physicochemical properties can influence NET interaction and leverage our findings to create NET-interfacing and NET-degrading particles. We fabricated a panel of particles of varying sizes (200 to 1000 nm) and charges (positive, neutral, negative) and found that positive charge is the main driver of NET-particle interaction, with smaller 200 nm positive particles having a 10-fold increase in binding compared to larger 1000 nm positive particles. Negative and neutral particles were mostly noninteracting, except for small negatively charged particles that exhibited very low levels of NET localization. Interaction strength of particles with NETs was quantified via shear flow assays and atomic force microscopy. This information was leveraged to create DNase-loaded particles that could adhere to NETs at varying degrees and therefore degrade NETs at different rates in vitro. Positively charged, 200 nm DNase-loaded particles showed the highest degree of interaction with NETs and therefore led to faster degradation compared with larger sizes, underscoring the importance of physicochemical design for NET-targeting drug delivery. Overall, this work provides fundamental knowledge of the drivers of particle-NET interaction and a basis for designing NET-targeting particles for various disease states.

Lung-homing nanoliposomes for early intervention in NETosis and inflammation during acute lung injury

Acute lung injury (ALI) is characterized by severe inflammation in lung tissue, excessive immune response and impaired lung function. In hospitalized high-risk patients and cases of secondary infection due to surgical contamination, it can lead to higher mortality rates and require immediate intervention. Currently, clinical treatments are limited in symptomatic therapy as mechanical ventilation and corticosteroids, having insufficient efficacy in mitigating the cause of progression to severe illness. Here we report a pulmonary targeting lung-homing nanoliposome (LHN) designed to attenuate excessive Neutrophil Extracellular Trap formation (NETosis) through sivelestat and DNase-1, coupled with an anti-inflammatory effect mediated by 25-hydroxycholesterol (25-HC), offering a promising intervention for the acute phase of ALI. Through intratracheal delivery, we intend prompt and constant action within the lungs to effectively prevent excessive NETosis. Isolated neutrophils from blood samples of severe ARDS patients demonstrated significant anti-NETosis effects, as well as reduced proinflammatory cytokine secretion. Furthermore, in a murine model of LPS-induced ALI, we confirmed improvements in lung histopathology, and early respiratory function. Also, attenuation of systemic inflammatory response syndrome (SIRS), with notable reductions in NETosis and neutrophil trafficking was investigated. This presents a targeted therapeutic approach that can be applied in early stages of high-risk patients to prevent severe pulmonary disease progression.

A biomimic anti-neuroinflammatory nanoplatform for active neutrophil extracellular traps targeting and spinal cord injury therapy

Traumatic spinal cord injury (SCI) always leads to severe neurological deficits and permanent damage. Neuroinflammation is a vital process of SCI and have become a promising target for SCI treatment. However, the neuroinflammation-targeted therapy would hinder the functional recovery of spinal cord and lead to the treatment failure. Herein, a biomimic anti-neuroinflammatory nanoplatform (DHCNPs) was developed for active neutrophil extracellular traps (NETs) targeting and SCI treatment. The curcumin-loaded liposome with the anti-inflammatory property acted as the core of the DHCNPs. Platelet membrane and neutrophil membrane were fused to form the biomimic hybrid membrane of the DHCNPs for hijacking neutrophils and neutralizing the elevated neutrophil-related proinflammatory cytokines, respectively. DNAse I modification on the hybrid membrane could achieve NETs degradation, blood spinal cord barrier, and neuron repair. Further studies proved that the DHCNPs could reprogram the multifaceted neuroinflammation and reverse the SCI process via nuclear factor kappa-B (NF-κB) pathway. We believe that the current study provides a new perspective for neuroinflammation inhibition and may shed new light on the treatment of SCI.

Neutrophil extracellular traps promote immune escape in hepatocellular carcinoma by up-regulating CD73 through Notch2

Immune escape is the main reason that immunotherapy is ineffective in hepatocellular carcinoma (HCC). Here, this study illustrates a pathway mediated by neutrophil extracellular traps (NETs) that can promote immune escape of HCC. Mechanistically, we demonstrated that NETs up-regulated CD73 expression through activating Notch2 mediated nuclear factor kappa B (NF-κB) pathway, promoting regulatory T cells (Tregs) infiltration to mediate immune escape of HCC. In addition, we found the similar results in mouse HCC models by hydrodynamic plasmid transfection. The treatment of deoxyribonuclease I (DNase I) could inhibit the action of NETs and improve the therapeutic effect of anti-programmed cell death protein 1 (PD-1). In summary, our results revealed that targeting of NETs was a promising treatment to improve the therapeutic effect of anti-PD-1.

Neutrophil Extracellular Traps in Tumors and Potential Use of Traditional Herbal Medicine Formulations for Its Regulation

Neutrophil extracellular traps (NETs) are extracellular fibers composed of deoxyribonucleic acid (DNA) and decorated proteins produced by neutrophils. Recently, NETs have been associated with the development of many diseases, including tumors. Herein, we reviewed the correlation between NETs and tumors. In addition, we detailed active compounds from traditional herbal medicine formulations that inhibit NETs, related nanodrug delivery systems, and antibodies that serve as "guiding moieties" to ensure targeted delivery to NETs. Furthermore, we discussed the strategies used by pathogenic microorganisms to evade NETs.

Genetically Engineered Cellular Nanovesicle as Targeted DNase I Delivery System for the Clearance of Neutrophil Extracellular Traps in Acute Lung Injury

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) are prevalent critical illnesses with a high mortality rate among patients in intensive care units. Neutrophil extracellular traps (NETs) are implicated in the pathogenesis of ALI/ARDS and represent a promising therapeutic target. However, the clinical application of deoxyribonuclease I (DNase I), the only drug currently available to clear NETs, is limited due to the lack of precise and efficient delivery strategies. Therefore, targeted delivery of DNase I to the inflamed lung remains a critical issue to be addressed. Herein, a novel biomimetic DNase I delivery system is developed (DCNV) that employs genetically and bioorthogonally engineered cellular nanovesicles for pulmonary NETs clearance. The CXC motif chemokine receptor 2 overexpressed cellular nanovesicles can mimic the inflammatory chemotaxis of neutrophils in ALI/ARDS, leading to enhanced lung accumulation. Furthermore, DNase I immobilized through bioorthogonal chemistry exhibits remarkable enzymatic activity in NETs degradation, thus restraining inflammation and safeguarding lung tissue in the lipopolysaccharide-induced ALI murine model. Collectively, the findings present a groundbreaking proof-of-concept in the utilization of biomimetic cellular nanovesicles to deliver DNase I for treating ALI/ARDS. This innovative strategy may usher in a new era in the development of pharmacological interventions for various inflammation-related diseases.

Fibronectin-targeted FUD and PEGylated FUD peptides for fibrotic diseases

Tissue fibrosis is characterized by excessive deposition of extracellular matrix (ECM) molecules. Fibronectin (FN) is a glycoprotein found in the blood and tissues, a key player in the assembly of ECM through interaction with cellular and extracellular components. Functional Upstream Domain (FUD), a peptide derived from an adhesin protein of bacteria, has a high binding affinity for the N-terminal 70-kDa domain of FN that plays a crucial role in FN polymerization. In this regard, FUD peptide has been characterized as a potent inhibitor of FN matrix assembly, reducing excessive ECM accumulation. Furthermore, PEGylated FUD was developed to prevent rapid elimination of FUD and enhance its systemic exposure in vivo. Herein, we summarize the development of FUD peptide as a potential anti-fibrotic agent and its application in experimental fibrotic diseases. In addition, we discuss how modification of the FUD peptide via PEGylation impacts pharmacokinetic profiles of the FUD peptide and can potentially contribute to anti-fibrosis therapy.