Kupffer Cell Isolation for Nanoparticle Toxicity Testing

The large majority of in vitro nanotoxicological studies have used immortalized cell lines for their practicality. However, results from nanoparticle ...

King's College London

We characterized a method to conjugate functional silver nanoparticles with vasoactive intestinal peptide (VIP), which could be used as a working model for further tailor-made applications based on VIP surface functionality. Despite sustained interest in the therapeutic applications of VIP, and the fact that its drugability could be largely improved by the attachament to functionalized metal nanoparticles, no methods have been described so far to obtain them.

Chemical synthesis and characterization of silver-protected vasoactive intestinal peptide nanoparticles.

Dendritic cells (DCs) are potent antigen-presenting cells capable of initiating a primary immune response and possess the ability to activate T cells and stimulate the growth and differentiation of B cells. DCs provide a direct connection between innate and adaptive immune response, and arise from bone marrow precursors that are present in immature forms in peripheral tissues, where they are prepared to capture antigens. DCs migrate from the peripheral tissues to the closest lymph nodes through afferent lymphatic vessels to present the foreign antigens, stimulating T-cell activation and initiating a cellular immune response. Moreover, it is known that DCs have an important role in various diseases and conditions involving the immune system, particularly in cancer and autoimmune disorders. For these reasons, targeting nanoparticles (NPs) to DCs provides a promising strategy for developing an efficient balanced and protective immune response. NPs can modulate the immune response and might be potentially useful as effective vaccine adjuvants for infectious disease and cancer therapy. The objective of this review is to present the latest advances in NP delivery methods targeting DCs, the mechanisms of action, potential effects, and therapeutic results of these systems and their future applications, such as improved vaccination strategies, cancer immunotherapy, and immunomodulatory treatments. From the clinical editor: Dendritic cells (DCs) are potent antigen-presenting cells capable of initiating a primary immune response and activating T and B cells. The role of DC-s can be considered as a bridge between innate and adaptive immunity. Targeting nanoparticles (NPs) to DCs can modulate the immune response and might be useful as vaccine adjuvants in infectious disease and cancer therapy.

Nanotechnology-based manipulation of dendritic cells for enhanced immunotherapy strategies.

In this work we describe the formulation and characterization of chemically modified polymeric nanocapsules incorporating the anticancer drug, quercetin, for the passive and active targeting to tumors. Folic acid was conjugated to poly(lactide-co-glycolide) (PLGA) polymer to facilitate active targeting to cancer cells. Two different methods for the conjugation of PLGA to folic acid were employed utilizing polyethylene glycol (PEG) as a spacer. Characterization of the conjugates was performed using FTIR and (1)H NMR studies. The PEG and folic acid content was independent of the conjugation methodology employed. PEGylation has shown to reduce the size of the nanocapsule; moreover, zeta-potential was shown to be polymer-type dependent. Comparative studies on the cytotoxicity and cellular uptake of the different formulations by HeLa cells, in the presence and absence of excess folic acid, were carried out using MTT assay and Confocal Laser Scanning Microscopy, respectively. Both results confirmed the selective uptake and cytotoxicity of the folic acid targeted nanocapsules to the folate enriched cancer cells in a folate-dependent manner. Finally, the passive tumor accumulation and the active targeting of the nanocapsules to folate-expressing cells were confirmed upon intravenous administration in HeLa or IGROV-1 tumor-bearing mice. The developed nanocapsules provide a system for targeted delivery of a range of hydrophobic anticancer drugs in vivo.

Polyethylene glycol conjugated polymeric nanocapsules for targeted delivery of quercetin to folate-expressing cancer cells in vitro and in vivo.

Neuropeptides are potentially valuable tools for clinical applications as they offer many distinct advantages over other bioactive molecules like proteins and monoclonal antibodies due to their reduced side effects and simple chemical modifications. Despite such advantages, the difficulty with neuropeptides often relies on their poor metabolic stability and reduced biological activity intervals. Among the neuropeptides, VIP has been identified as a potentially bioactive agent for inflammatory, neurodegenerative, and cancer-related diseases. However, the effective translation of preclinical studies related to VIP to clinical realities faces several major challenges, most of which are commonplace for other neuropeptides. Here, we present recent studies aimed at developing nanostructured organic and inorganic systems either for the appropriate delivery of VIP or for VIP targeting. These technologies stand as an alternative starting point for chemical manipulations of the neuropeptides in order to improve potency, selectivity, or pharmacokinetic parameters.

Vasoactive Intestinal Peptide (VIP) Nanoparticles for Diagnostics and for Controlled and Targeted Drug Delivery.

α-Synuclein (αSyn) is a 140-residue amyloid-forming protein whose aggregation is linked to Parkinson's disease (PD). It has also been found to play a critical role in the immune imbalance that accompanies disease progression, a characteristic that has prompted the search for an effective αSyn-based immunotherapy. In this study, we have simultaneously exploited two important features of certain heat-shock proteins (HSPs): their classical "chaperone" activities and their recently discovered and diverse "immunoactive" properties. In particular, we have explored the immune response elicited by immunization of C57BL/6 mice with an αSyn/Hsp70 protein combination in the absence of added adjuvant. Our results show differential effects for mice immunized with the αSyn/Hsp70 complex, including a restrained αSyn-specific (IgM and IgG) humoral response as well as minimized alterations in the Treg (CD4(+)CD25(+)Foxp3(+)) and Teff (CD4(+)Foxp3(-)) cell populations, as opposed to significant changes in mice immunized with αSyn and Hsp70 alone. Furthermore, in vitro-stimulated splenocytes from immunized mice showed the lowest relative response against αSyn challenge for the "αSyn/Hsp70" experimental group as measured by IFN-γ and IL-17 secretion, and higher IL-10 levels when stimulated with LPS. Finally, serum levels of Th1-cytokine IFN-γ and immunomodulatory IL-10 indicated a unique shift toward an immunomodulatory/immunoprotective phenotype in mice immunized with the αSyn/Hsp70 complex. Overall, we propose the use of functional "HSP-chaperoned amyloid/aggregating proteins" generated with appropriate HSP-substrate protein combinations, such as the αSyn/Hsp70 complex, as a novel strategy for immune-based intervention against synucleinopathies and other amyloid or "misfolding" neurodegenerative disorders.

Chaperoned amyloid proteins for immune manipulation: α-Synuclein/Hsp70 shifts immunity toward a modulatory phenotype.

To formulate f-MWNTs-cationic liposome hybrids for the simultaneous delivery of siPLK1 and doxorubicin to cancer cells.

Cationic Liposome- Multi-Walled Carbon Nanotubes Hybrids for Dual siPLK1 and Doxorubicin Delivery In Vitro.

Clinical applications of curcumin for the treatment of cancer and other chronic diseases have been mainly hindered by its short biological half-life and poor water solubility. Nanotechnology-based drug delivery systems have the potential to enhance the efficacy of poorly soluble drugs for systemic delivery. This study proposes the use of poly(lactic-co-glycolic acid) (PLGA)-based polymeric oil-cored nanocapsules (NCs) for curcumin loading and delivery to colon cancer in mice after systemic injection. Formulations of different oil compositions are prepared and characterized for their curcumin loading, physico-chemical properties, and shelf-life stability. The results indicate that castor oil-cored PLGA-based NC achieves high drug loading efficiency (≈18% w(drug)/w(polymer)%) compared to previously reported NCs. Curcumin-loaded NCs internalize more efficiently in CT26 cells than the free drug, and exert therapeutic activity in vitro, leading to apoptosis and blocking the cell cycle. In addition, the formulated NC exhibits an extended blood circulation profile compared to the non-PEGylated NC, and accumulates in the subcutaneous CT26-tumors in mice, after systemic administration. The results are confirmed by optical and single photon emission computed tomography/computed tomography (SPECT/CT) imaging. In vivo growth delay studies are performed, and significantly smaller tumor volumes are achieved compared to empty NC injected animals. This study shows the great potential of the formulated NC for treating colon cancer.

Rebecca Klippstein

Institute of Pharmaceutical Science

King's College London

Kupffer Cell Isolation for Nanoparticle Toxicity Testing

Rebecca Klippstein

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Institute of Pharmaceutical Science

King's College London

Kupffer Cell Isolation for Nanoparticle Toxicity Testing

Institute of Pharmaceutical Science