Highly selective organ distribution and cellular uptake of inorganic-organic hybrid nanoparticles customized for the targeted delivery of glucocorticoids

Characterizing Extracellular Vesicles Generated from the Integra CELLine Culture System and Their Endocytic Pathways for Intracellular Drug Delivery

Extracellular vesicles (EVs) have attracted great attention as promising intracellular drug delivery carriers. While the endocytic pathways of small EVs (sEVs, <200 nm) have been reported, there is limited understanding of large EVs (lEVs, >200 nm), despite their potential applications for drug delivery. Additionally, the low yield of EVs during isolation remains a major challenge in their application. Herein, we aimed to compare the endocytic pathways of sEVs and lEVs using MIA PaCa-2 pancreatic cancer cell-derived EVs as models and to explore the efficiency of their production. The cellular uptake of EVs by MIA PaCa-2 cells was assessed and the pathways were investigated with the aid of endocytic inhibitors. The yield and protein content of sEVs and lEVs from the Integra CELLine culture system and the conventional flasks were compared. Our findings revealed that both sEVs and lEVs produced by the Integra CELLine system entered their parental cells via multiple routes, including caveolin-mediated endocytosis, clathrin-mediated endocytosis, and actin-dependent phagocytosis or macropinocytosis. Notably, caveolin- and clathrin-mediated endocytosis were more prominent in the uptake of sEVs, while actin-dependent phagocytosis and macropinocytosis were significant for both sEVs and lEVs. Compared with conventional flasks, the Integra CELLine system demonstrated a 9-fold increase in sEVs yield and a 6.5-fold increase in lEVs yield, along with 3- to 4-fold higher protein content per 1010 EVs. Given that different endocytic pathways led to distinct intracellular trafficking routes, this study highlights the unique potentials of sEVs and lEVs for intracellular cargo delivery. The Integra CELLine proves to be a highly productive and cost-effective system for generating EVs with favourable properties for drug delivery.

Glucocorticoid Nanoparticles Show Full Therapeutic Efficacy in a Mouse Model of Acute Lung Injury and Concomitantly Reduce Adverse Effects

Glucocorticoids (GCs) are widely used to treat inflammatory disorders such as acute lung injury (ALI). Here, we explored inorganic-organic hybrid nanoparticles (IOH-NPs) as a new delivery vehicle for GCs in a mouse model of ALI. Betamethasone (BMZ) encapsulated into IOH-NPs (BNPs) ameliorated the massive infiltration of neutrophils into the airways with a similar efficacy as the free drug. This was accompanied by a potent inhibition of pulmonary gene expression and secretion of pro-inflammatory mediators, whereas the alveolar-capillary barrier integrity was only restored by BMZ in its traditional form. Experiments with genetically engineered mice identified myeloid cells and alveolar type II (AT II) cells as essential targets of BNPs in ALI therapy, confirming their high cell-type specificity. Consequently, adverse effects were reduced when using IOH-NPs for GC delivery. BNPs did not alter T and B cell numbers in the blood and also prevented the induction of muscle atrophy after three days of treatment. Collectively, our data suggest that IOH-NPs target GCs to myeloid and AT II cells, resulting in full therapeutic efficacy in the treatment of ALI while being associated with reduced adverse effects.

High-Throughput Single-Cell Analysis of Nanoparticle-Cell Interactions

Understanding nanoparticle-cell interactions at single-nanoparticle and single-cell resolutions is crucial to improving the design of next-generation nanoparticles for safer, more effective, and more efficient applications in nanomedicine. This review focuses on recent advances in the continuous high-throughput analysis of nanoparticle-cell interactions at the single-cell level. We highlight and discuss the current trends in continual flow high-throughput methods for analyzing single cells, such as advanced flow cytometry techniques and inductively coupled plasma mass spectrometry methods, as well as their intersection in the form of mass cytometry. This review further discusses the challenges and opportunities with current single-cell analysis approaches and provides proposed directions for innovation in the high-throughput analysis of nanoparticle-cell interactions.

Effects of morphology and size of nanoscale drug carriers on cellular uptake and internalization process: a review

In the field of targeted drug delivery, the effects of size and morphology of drug nanocarriers are of great importance and need to be discussed in depth. To be concise, among all the various shapes of nanocarriers, rods and tubes with a narrow cross-section are the most preferred shapes for the penetration of a cell membrane. In this regard, several studies have focused on methods to produce nanorods and nanotubes with controlled optimized size and aspect ratio (AR). Additionally, a non-spherical orientation could affect the cellular uptake process while a tangent angle of less than 45° is better at penetrating the membrane, and Ω = 90° is beneficial. Moreover, these nanocarriers show different behaviors when confronting diverse cells whose fields should be investigated in future studies. In this survey, a comprehensive classification based on carrier shape is first submitted. Then, the most commonly used methods for control over the size and shape of the carriers are reviewed. Finally, influential factors on the cellular uptake and internalization processes and related analytical methods for evaluating this process are discussed.

A carrier-free metal-organic hybrid nanoassembly with combination anti-viral and hepato-protective activity for hepatitis B treatment

Hepatitis B represents a major global public health burden, which is caused by the hepatitis B virus (HBV) with a high infection rate. Although several anti-HBV drugs have been developed for clinical treatment of hepatitis B, the current therapeutic strategies still suffer from undeniable adverse effects, insufficient efficacy after systemic administration and chronic inflammation. Here, we develop a carrier-free metal-organic hybrid nanoassembly that is co-loaded with tenofovir (TFV), an anti-viral agent and phosphorylated glycyrrhetinic acid (GAP), an anti-inflammatory compound (TFV/GAP/NA) to enhance the anti-HBV effect and alleviate the inflammatory response for hepatitis B treatment. The nanoassembly is easily prepared through the ionic interactions between the anionic phosphonate/phosphate groups from TFV/GAP and the zirconium cation, which has a stable nanostructure and a high drug-loading capacity. The nanoassembly prolongs the circulation time with reduced drug leakage in the blood and elevates drug accumulation in the liver after intravascular administration. After internalization mediated by the GAP ligand-GA receptor interaction, TFV/GAP/NA disassembles by the phosphatase-triggered degradation of the phosphate ester bonds in GAP and releases TFV, GAP and GA within the HBV-positive hepatocytes. The released TFV interferes with the HBV polymerase to inhibit the viral DNA replication, while the released GAP and GA suppress the pro-inflammatory protein expression. In mouse models, treatment with TFV/GAP/NA inhibits HBV production and alleviates inflammation-mediated liver injury.

Foscarnet-Type Inorganic-Organic Hybrid Nanoparticles for Effective Antiviral Therapy

[ZrO]²⁺[(FCN)_0.4(OH)_0.8]^2- and Gd³⁺[FCN]^3- inorganic-organic hybrid nanoparticles (IOH-NPs) are novel saline antiviral nanocarriers with foscarnet (FCN) as a drug anion. FCN as a pyrophosphate analogue serves as a prototype of a viral DNA polymerase inhibitor. FCN is used for the treatment of herpesvirus infections, including the drug-resistant cytomegalovirus (CMV) and herpes simplex viruses, HSV-1 and HSV-2. The novel [ZrO]²⁺[(FCN)_0.4(OH)_0.8]^2- and Gd³⁺[FCN]^3- IOH-NPs are characterized by aqueous synthesis, small size (20-30 nm), low material complexity, high biocompatibility, and high drug load (up to 44 wt % FCN per nanoparticle). The antiviral activity of the FCN-type IOH-NPs is probed for the human cytomegalovirus (HCMV). Moreover, the uptake of FCN-type IOH-NPs into vesicles, cytoplasm, and nuclei of nonphagocytic lung epithelial cells is evaluated. As a result, a promising antiviral activity of the FCN-type IOH-NPs that significantly outperforms freely dissolved FCN at the level of clinical formulations is observed, encouraging a future use of FCN-type IOH-NPs for the delivery of antivirals against respiratory viruses.

The Role of Glucocorticoids in Inflammatory Diseases

For more than 70 years, glucocorticoids (GCs) have been a powerful and affordable treatment option for inflammatory diseases. However, their benefits do not come without a cost, since GCs also cause side effects. Therefore, strong efforts are being made to improve their therapeutic index. In this review, we illustrate the mechanisms and target cells of GCs in the pathogenesis and treatment of some of the most frequent inflammatory disorders affecting the central nervous system, the gastrointestinal tract, the lung, and the joints, as well as graft-versus-host disease, which often develops after hematopoietic stem cell transplantation. In addition, an overview is provided of novel approaches aimed at improving GC therapy based on chemical modifications or GC delivery using nanoformulations. GCs remain a topic of highly active scientific research despite being one of the oldest class of drugs in medical use.

Influence of Cell Membrane Wrapping on the Cell-Porous Silicon Nanoparticle Interactions

Biohybrid nanosystems represent the cutting-edge research in biofunctionalization of micro- and nano-systems. Their physicochemical properties bring along advantages in the circulation time, camouflaging from the phagocytes, and novel antigens. This is partially a result of the qualitative differences in the protein corona, and the preferential targeting and uptake in homologous cells. However, the effect of the cell membrane on the cellular endocytosis mechanisms and time has not been fully evaluated yet. Here, the effect is assessed by quantitative flow cytometry analysis on the endocytosis of hydrophilic, negatively charged porous silicon nanoparticles and on their membrane-coated counterparts, in the presence of chemical inhibitors of different uptake pathways. Principal component analysis is used to analyze all the data and extrapolate patterns to highlight the cell-specific differences in the endocytosis mechanisms. Furthermore, the differences in the composition of static protein corona between naked and coated particles are investigated together with how these differences affect the interaction with human macrophages. Overall, the presence of the cell membrane only influences the speed and the entity of nanoparticles association with the cells, while there is no direct effect on the endocytosis pathways, composition of protein corona, or any reduction in macrophage-mediated uptake.

Glucocorticoids delivered by inorganic-organic hybrid nanoparticles mitigate acute graft-versus-host disease and sustain graft-versus-leukemia activity

Glucocorticoids (GCs) are widely used to treat acute graft-versus-host disease (aGvHD) due to their immunosuppressive activity, but they also reduce the beneficial graft-versus-leukemia (GvL) effect of the allogeneic T cells contained in the graft. Here, we tested whether aGvHD therapy could be improved by delivering GCs with the help of inorganic-organic hybrid nanoparticles (IOH-NPs) that preferentially target myeloid cells. IOH-NPs containing the GC betamethasone (BMP-NPs) efficiently reduced morbidity, mortality, and tissue damage in a totally MHC mismatched mouse model of aGvHD. Therapeutic activity was lost in mice lacking the GC receptor (GR) in myeloid cells, confirming the cell type specificity of our approach. BMP-NPs had no relevant systemic activity but suppressed cytokine and chemokine gene expression locally in the small intestine, which presumably explains their mode of action. Most importantly, BMP-NPs delayed the development of an adoptively transferred B cell lymphoma better than the free drug, although the overall incidence was unaffected. Our findings thus suggest that employing IOH-NPs could diminish the risk of relapse associated with GC therapy of aGvHD patients while still allowing to efficiently ameliorate the disease.