Nanomedicine Carriers Research Articles

Photothermally activatable PDA immune nanomedicine combined with PD-L1 checkpoint blockade for antimetastatic cancer photoimmunotherapy.

Photothermal therapy (PTT) has shown promising potential and bright prospects in damaging primary tumors; however, it is limited to metastatic and recrudescent tumors as PTT requires straightforward light irradiation. Moreover, metastatic and recrudescent tumor immunosuppression due to host T-cell antitumor activity is dramatically impeded because of programmed cell death 1 ligand (PD-L1) and programmed cell death receptor 1 (PD-1) pathways and immune checkpoint blockade (ICB) therapy. In this work, we demonstrate that PTT combined with ICB could not only eliminate primary tumors, but also prevent tumor metastasis to the lungs/liver. In particular, we have designed immunoadjuvant nanomedicine carriers on the basis of polydopamine (PDA) simultaneously loaded with resiquimod (R848)-a kind of toll-like receptor 7 (TLR7) agonist-and carbon dots (CDs)-a fluorescent agent. This nanomedicine is defined as PDA-PEG-R848-CD nanoparticle (NP). The multitasking PDA-PEG-R848-CD NPs can destroy 4T1 breast tumors by PTT under near-infrared laser irradiation in addition to generating tumor-associated antigens. Moreover, the PTT effect triggered the release of R848, thereby inducing a strong antitumor immune response. Meanwhile, this synergistic therapy also shows the abscopal effects by completely inhibiting the growth of untreated distant tumors by effectively triggering the tumors infiltrated by CD3/CD8. Such findings suggest that PDA-PEG-R848-CD NPs could significantly potentiate the systemic therapeutic efficiency of PD-L1 checkpoint blockade therapy by activating both innate and adaptive immune systems in the body.

Synthesis, Characterization and In Vitro Evaluation of Dual pH/Redox Sensitive Marine Laminarin-Based Nanomedicine Carrier Biomaterial for Cancer Therapy.

In order to improve the anti-cancer therapy efficiency of hydrophobic drugs such as curcumin (Cur), a novel dual pH/redox sensitive marine laminarin-based nanomedicine carrier biomaterial with photo-dynamic therapy (PDT) was synthesized in this study. The new synthetic chemical structure, named as Hematin-Laminarin-Dithiodipropionic Acid-MGK (HLDM), was characterized by 1H-NMR and IR. The Cur-loaded micelles were then prepared via dialysis method. The HLDM could self-assemble into micelles in water with hydrodynamic diameter of 135±15 nm. The particle size, zeta potential and morphology of micelles were detected by transmission electron microscope (TEM). Interestingly, the in vitro release experiment showed that the release amount of Cur-loaded HLDM micelles could reach 80% in the pH and redox sensitive environment. Furthermore, cell study showed that the Cur-loaded HLDM micelles had stronger cellular uptake and cytotoxicity to MCF-7 cells than that of HLDM. The multifunctional marine laminarin based nanomedicine carrier biomaterial can be used for new drug delivery systems with dual pH/redox sensitivity for cancer therapy.

Biological voyage of solid lipid nanoparticles: a proficient carrier in nanomedicine.

This review projects the prospects and issues faced by solid lipid nanoparticles (SLNs) in current scenarios, specially related to its clinical implementation and effectiveness. We re-examine the basic concept of biobehavior and movement of SLNs as a nanomedicine carrier. The extensive survey of the uptake and absorption mechanism from different routes, distribution pattern, targeting efficiency, effect of surface functionalization on biodistribution, elimination pathways and toxic effects have been documented. In general, the objective of this review is to boost our knowledge about the interaction of SLNs with the bioenvironment, their movement in, and effect on, a living system and future prospects.

Targeting Rapamycin to Podocytes Using a Vascular Cell Adhesion Molecule-1 (VCAM-1)-Harnessed SAINT-Based Lipid Carrier System.

Together with mesangial cells, glomerular endothelial cells and the basement membrane, podocytes constitute the glomerular filtration barrier (GFB) of the kidney. Podocytes play a pivotal role in the progression of various kidney-related diseases such as glomerular sclerosis and glomerulonephritis that finally lead to chronic end-stage renal disease. During podocytopathies, the slit-diaphragm connecting the adjacent podocytes are detached leading to severe loss of proteins in the urine. The pathophysiology of podocytopathies makes podocytes a potential and challenging target for nanomedicine development, though there is a lack of known molecular targets for cell selective drug delivery. To identify VCAM-1 as a cell-surface receptor that is suitable for binding and internalization of nanomedicine carrier systems by podocytes, we investigated its expression in the immortalized podocyte cell lines AB8/13 and MPC-5, and in primary podocytes. Gene and protein expression analyses revealed that VCAM-1 expression is increased by podocytes upon TNFα-activation for up to 24 h. This was paralleled by anti-VCAM-1 antibody binding to the TNFα-activated cells, which can be employed as a ligand to facilitate the uptake of nanocarriers under inflammatory conditions. Hence, we next explored the possibilities of using VCAM-1 as a cell-surface receptor to deliver the potent immunosuppressant rapamycin to TNFα-activated podocytes using the lipid-based nanocarrier system Saint-O-Somes. Anti-VCAM-1-rapamycin-SAINT-O-Somes more effectively inhibited the cell migration of AB8/13 cells than free rapamycin and non-targeted rapamycin-SAINT-O-Somes indicating the potential of VCAM-1 targeted drug delivery to podocytes.

Lung toxicity of biodegradable nanoparticles.

Biodegradable nanoparticles exhibit high potentialities for local or systemic drug delivery through lung administration making them attractive as nanomedicine carriers. However, since particulate matter or some inorganic manufactured nanoparticles exposed to lung cells have provoked cytotoxic effects, inflammatory and oxidative stress responses, it becomes important to investigate nanomedicine toxicity towards the lungs. This is the reason why, in the present review, the behavior of biodegradable nanoparticles towards the different parts of the respiratory tract as well as the toxicological consequences, measured on several models in vitro, ex vivo or in vivo, are described. Taken all together, the different studies carried out so far conclude on no or slight toxicity of biodegradable nanoparticles.

Drug release from nanomedicines: selection of appropriate encapsulation and release methodology

The characterization of encapsulation efficiency and in vitro drug release from nanoparticle-based formulations often requires the separation of nanoparticles from unencapsulated drug. Inefficient separation of nanoparticles from the medium in which they are dispersed can lead to inaccurate estimates of encapsulation efficiency and drug release. This study establishes dynamic light scattering as a simple method for substantiation of the effectiveness of the separation process. Colistin-loaded liposomes, as an exemplar nano-sized delivery particle, were diluted to construct a calibration curve relating the amount of light scattering to liposome concentration. Dynamic light scattering revealed that, in the case of ultracentrifugation and centrifugal ultrafiltration, approximately 2.9% of the total liposomes remained in supernatants or filtrates, respectively. In comparison, filtrates obtained using pressure ultrafiltration contained less than 0.002% of the total liposomes from the formulation. Subsequent release studies using dialysis misleadingly implied a slow release of colistin over >48 h. In contrast, pressure ultrafiltration revealed immediate equilibration to the equilibrium distribution of colistin between the liposome and aqueous phases upon dilution. Pressure ultrafiltration is therefore recommended as the optimal method of choice for studying release kinetics of drug from nanomedicine carriers.

Self-Assembled Nanostructures of Homopolymer and Diblock Copolymer Blends in a Selective Solvent

Self-assembled nanostructures of amphiphilic block copolymers hold great promise for applications in nanomedicine. Blending polymers provides an effective way to produce multifunctional drug delivery vesicles at micro- and nanoscales. Here we investigate the self-assembly of homopolymer and diblock copolymer blends in a selective solvent by using the self-consistent field method. It is found that self-assembled nanostructures of different sizes and shapes (e.g., vesicles, circle- and line-like micelles, and their mixtures) can be obtained by varying the concentration and composition of the diblock copolymer. As the chain length or concentration of the homopolymer changes, morphological transitions may occur among the different nanostructures. On the basis of a number of simulations under various conditions, a phase diagram of aggregate morphologies is constructed with respect to the mixture ratio and the homopolymer chain length. The theoretical method presented here could be used to design novel nanomedicine carriers and to optimize their sizes and shapes for specific biomedical applications.