MRI Detection of Lymph Node Metastasis through Molecular Targeting of C-C Chemokine Receptor Type 2 and Monocyte Hitchhiking

Precision-Guided Stealth Missiles in Biomedicine: Biological Carrier-Mediated Nanomedicine Hitchhiking Strategy

Nanodrug delivery systems (NDDS) have demonstrated broad application prospects in disease treatment, prevention, and diagnosis due to several advantages, including functionalization capability, high drug-loading capacity, drug stability protection, and the enhanced permeability and retention (EPR) effect. However, their clinical translation still faces multiple challenges, including rapid clearance by the reticuloendothelial system (RES), poor targeting specificity, and insufficient efficiency in crossing biological barriers. To address these limitations, researchers have developed the biological carrier-mediated nanomedicine hitchhiking strategy (BCM-NHS), which leverages circulating cells, proteins, or bacteria as natural "mobile carriers" to enhance drug delivery. This approach enables nanocarriers to inherit the intrinsic biological properties, endowing them with immune evasion, prolonged circulation, dynamic targeting, biocompatibility, biodegradability, and naturally optimized biological interfaces. Here, a systematic overview of the BCM-NHS is provided. First, the review delves into the methods of nanoparticles (NPs) binding and immobilization, encompassing both the surface-attachment-mediated "backpack" strategy and the encapsulation-based "Trojan horse" strategy. Second, the classification of biological carriers, including both cell-based and non-cell-based carriers, is elucidated. Third, the physical properties and release mechanisms of these nanomaterials are thoroughly described. Finally, the latest applications of BCM-NHS in therapeutic and diagnostic contexts across various disease models including tumor, ischemic stroke, and pneumonia are highlighted.

Developing Therapeutically Enhanced Extracellular Vesicles for Atherosclerosis Therapy

Atherosclerosis is a chronic condition and the leading cause of death worldwide. While statin therapy is the clinical standard, many patients still experience acute cardiovascular events.  To develop better therapies, the group previously delivered microRNA-145 (miR-145) via micellar nanoparticles to vascular smooth muscle cells (VSMCs) to inhibit atherosclerosis. However, for chronic diseases requiring repeat dosing, synthetic nanoparticles have drawbacks such as immunogenic response and low delivery efficiency. To meet this challenge, therapeutically enhanced extracellular vesicles (EVs) are engineered as a biologically-derived nanoparticle modality to mitigate atherosclerosis. A novel strategy is employed to load miR-145 into EVs using ExoMotifs-short miRNA sequences that facilitate miR cargo loading. EVs are further functionalized with a monocyte chemoattractant 1 (MCP-1) peptide, which binds to C-C chemokine receptor 2 upregulated in pathogenic VSMCs. Mouse aortic smooth muscle cell MCP-1-miR-145 EVs restored VSMC gene expression and function in vitro. Moreover, compared to miR-145-loaded synthetic nanoparticles, MCP-1-miR-145 EVs exerted similar therapeutic effects but with 25,000x less miR-145 cargo. Lastly, MCP-1-miR-145 EVs inhibited plaque growth in mid-stage ApoE-/- atherosclerotic mice at a miR-145 dose 5000x less than synthetic nanoparticles. Collectively, it is demonstrated that genetic engineering of VSMCs with miR-145 produces therapeutically boosted EVs that reduce atherosclerosis plaque burden.

Endothelial-targeting miR-145 micelles restore barrier function and exhibit atheroprotective effects

Atherosclerosis remains the leading cause of death worldwide and is characterized by the accumulation of plaque beneath the endothelium. MicroRNA-145-5p (miR-145), which is downregulated in atherosclerosis, has been shown to mitigate plaque development by promoting the contractile vascular smooth muscle cell (VSMC) phenotype. Previously, our lab found that miR-145 micelles conjugated with MCP-1 peptides were able to inhibit atherosclerosis by targeting diseased VSMC via C-C chemokine receptor 2 (CCR2). Diseased endothelial cells similarly express CCR2; however, the impact of miR-145 micelles on endothelial cell function has not been explored. Thus, in this study, the in vitro therapeutic effects of miR-145 micelles in modulating the endothelium during atherosclerosis are evaluated. To that end, the MCP-1 peptide density on the micelle surface was first optimized for activated endothelial cell binding, followed by loading miR-145 into micelles with the optimal MCP-1 ratio. Following characterization, miR-145 micelle treatment of activated endothelial cells resulted in efficient miR-145 transfection, upregulation of atheroprotective genes, and suppression of atherogenic genes. Furthermore, the treatment enhanced the integrity of endothelial tight junctions and reduced monocyte migration. This work establishes miR-145 micelles as an effective nanotherapeutic for restoring endothelial cell health in cardiovascular disease for the first time.

Macrophage membrane enveloped on double-locked nanoplatform with right-side-out orientation to improving precise theranostic for atherosclerosis

A right-side-out orientated self-assembly of cell membrane-camouflaged theranostic nanoplatform is crucial for ensuring their biological functionality inherited from the source cells. However, the low specificity and fluorescence background interference hampered reliable assessment of lipids content in plaques. In this work, a spontaneous right-side-out coupling-driven ROS-responsive theranostic nanoplatform has been developed to enhance accumulation within atherosclerotic plaques, target lipids imaging in plaques, reduce the interference from background fluorescence and inhibit the progression of atherosclerosis (AS). A ROS-responsive lipid-unlocked fluorescent probe is constructed, followed by loading rapamycin (RAP) for safe and efficient AS therapy. Moreover, the theranostic nanoplatform is functionalized with PS-targeted peptide for binding to phosphatidylserine located on the inner leaflet of the macrophage membrane, harvesting a right-side-out-orientated coating theranostics formulation (M-TPCR) for the reliable imaging of lipids in lipids-sufficient Hela cells, foam cells and atherosclerotic plaques while keeping in fluorescence off in lipid-deficient environments, such as M0 macrophages, M1 macrophages and blood. Most importantly, the FL signals of M-TPCR are positively correlated with lipid content across foam cells, isolated aorta or aortic root sections, confirming its reliability in indicating plaques. Hence, M-TPCR provides a powerful approach for developing the biomimetic cell membrane camouflaged nanotechnology and delivers an impressive potential on the therapeutic efficacy monitoring.

The evolution of immune profiling: will there be a role for nanoparticles?

Immune profiling provides insights into the functioning of the immune system, including the distribution, abundance, and activity of immune cells. This understanding is essential for deciphering how the immune system responds to pathogens, vaccines, tumors, and other stimuli. Analyzing diverse immune cell types facilitates the development of personalized medicine approaches by characterizing individual variations in immune responses. With detailed immune profiles, clinicians can tailor treatment strategies to the specific immune status and needs of each patient, maximizing therapeutic efficacy while minimizing adverse effects. In this review, we discuss the evolution of immune profiling, from interrogating bulk cell samples in solution to evaluating the spatially-rich molecular profiles across intact preserved tissue sections. We also review various multiplexed imaging platforms recently developed, based on immunofluorescence and imaging mass spectrometry, and their impact on the field of immune profiling. Identifying and localizing various immune cell types across a patient's sample has already provided important insights into understanding disease progression, the development of novel targeted therapies, and predicting treatment response. We also offer a new perspective by highlighting the unprecedented potential of nanoparticles (NPs) that can open new horizons in immune profiling. NPs are known to provide enhanced detection sensitivity, targeting specificity, biocompatibility, stability, multimodal imaging features, and multiplexing capabilities. Therefore, we summarize the recent developments and advantages of NPs, which can contribute to advancing our understanding of immune function to facilitate precision medicine. Overall, NPs have the potential to offer a versatile and robust approach to profile the immune system with improved efficiency and multiplexed imaging power.

Porphyrin-Based Self-Assembled Nanoparticles for PET/MR Imaging of Sentinel Lymph Node Metastasis

Diagnosing of lymph node metastasis is challenging sometimes, and multimodal imaging offers a promising method to improve the accuracy. This work developed porphyrin-based nanoparticles (68Ga-F127-TAPP/TCPP(Mn) NPs) as PET/MR dual-modal probes for lymph node metastasis imaging by a simple self-assembly method. Compared with F127-TCPP(Mn) NPs, F127-TAPP/TCPP(Mn) NPs synthesized by amino-porphyrins (TAPP) doping can not only construct PET/MR bimodal probes but also improve the T1 relaxivity (up to 456%). Moreover, T1 relaxivity can be adjusted by altering the molar ratio of TAPP/TCPP(Mn) and the concentration of F127. However, a similar increase in T1 relaxivity was not observed in the F127-TCPP/TCPP(Mn) NPs, which were synthesized using carboxy-porphyrins (TCPP) doping. In a breast cancer lymph node metastasis mice model, subcutaneous injection of 68Ga-F127-TAPP/TCPP(Mn) NPs through the hind foot pad, the normal lymph nodes and metastatic lymph nodes were successfully distinguished based on the difference of PET standard uptake values and MR signal intensities. Furthermore, the dark brown F127-TAPP/TCPP(Mn) NPs demonstrated the potential for staining and mapping lymph nodes. This study provides valuable insights into developing and applying PET/MR probes for lymph node metastasis imaging.

Investigation of Basolateral Targeting Micelles for Drug Delivery Applications in Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease (ADPKD) is a complex disorder characterized by uncontrolled renal cyst growth, leading to kidney function decline. The multifaceted nature of ADPKD suggests that single-pathway interventions using individual small molecule drugs may not be optimally effective. As such, a strategy encompassing combination therapy that addresses multiple ADPKD-associated signaling pathways could offer synergistic therapeutic results. However, severe off-targeting side effects of small molecule drugs pose a major hurdle to their clinical transition. To address this, we identified four drug candidates from ADPKD clinical trials, bardoxolone methyl (Bar), octreotide (Oct), salsalate (Sal), and pravastatin (Pra), and incorporated them into peptide amphiphile micelles containing the RGD peptide (GRGDSP), which binds to the basolateral surface of renal tubules via integrin receptors on the extracellular matrix. We hypothesized that encapsulating drug combinations into RGD micelles would enable targeting to the basolateral side of renal tubules, which is the site of disease, via renal secretion, leading to superior therapeutic benefits compared to free drugs. To test this, we first evaluated the synergistic effect of drug combinations using the 20% inhibitory concentration for each drug (IC20) on renal proximal tubule cells derived from Pkd1flox/-:TSLargeT mice. Next, we synthesized and characterized the RGD micelles encapsulated with drug combinations and measured their in vitro therapeutic effects via a 3D PKD growth model. Upon both IV and IP injections in vivo, RGD micelles showed a significantly higher accumulation in the kidneys compared to NT micelles, and the renal access of RGD micelles was significantly reduced after the inhibition of renal secretion. Specifically, both Bar+Oct and Bar+Sal in the RGD micelle treatment showed enhanced therapeutic efficacy in ADPKD mice (Pkd1fl/fl;Pax8-rtTA;Tet-O-Cre) with a significantly lower KW/BW ratio and cyst index as compared to PBS and free drug-treated controls, while other combinations did not show a significant difference. Hence, we demonstrate that renal targeting through basolateral targeting micelles enhances the therapeutic potential of combination therapy in genetic kidney disease.

Oral delivery of nanomedicine for genetic kidney disease

Chronic and genetic kidney diseases such as autosomal dominant polycystic kidney disease (ADPKD) have few therapeutic options, and clinical trials testing small molecule drugs have been unfavorable due to low kidney bioavailability and adverse side effects. Although nanoparticles can be designed to deliver drugs directly to the diseased site, there are no kidney-targeted nanomedicines clinically available, and most FDA-approved nanoparticles are administered intravenously which is not ideal for chronic diseases. To meet these challenges of chronic diseases, we developed a biomaterials-based strategy using chitosan particles (CP) for oral delivery of therapeutic, kidney-targeting peptide amphiphile micelles (KMs). We hypothesized that encapsuling KMs into CP would enhance the bioavailability of KMs upon oral administration given the high stability of chitosan in acidic conditions and mucoadhesive properties enabling absorption within the intestines. To test this, we evaluated the mechanism of KM access to the kidneys via intravital imaging and investigated the KM biodistribution in a porcine model. Next, we loaded KMs carrying the ADPKD drug metformin into CP (KM-CP-met) and measured in vitro therapeutic effect. Upon oral administration in vivo, KM-CP-met showed significantly greater bioavailability and accumulation in the kidneys as compared to KM only or free drug. As such, KM-CP-met treatment in ADPKD mice (Pkd1fl/fl;Pax8-rtTA;Tet-O-Cre which develops the disease over 120 days and mimics the slow development of ADPKD) showed enhanced therapeutic efficacy without affecting safety despite repeated treatment. Herein, we demonstrate the potential of KM-CP as a nanomedicine strategy for oral delivery for the long-term treatment of chronic kidney diseases.