RESUMO
Chitosan-based nanoparticles (NPs) are widely used in drug delivery, device-based therapy, tissue engineering, and medical imaging. In this aspect, a clear understanding of how physicochemical properties of these NPs affect the cytological response is in high demand. The objective of this study is to evaluate the effect of surface charge on cellular uptake profiles (rate and amount) and intracellular trafficking. We fabricate three kinds of NPs (â¼ 215 nm) with different surface charge via SPG membrane emulsification technique and deposition method. They possess uniform size as well as identical other physicochemical properties, minimizing any differences between the NPs except for surface charge. Moreover, we extend our research to eight cell lines, which could help to obtain a representative conclusion. Results show that the cellular uptake rate and amount are both positively correlated with the surface charge in all cell line. Subsequent intracellular trafficking indicates that some of positively charged NPs could escape from lysosome after being internalized and exhibit perinuclear localization, whereas the negatively and neutrally charged NPs prefer to colocalize with lysosome. These results are critical in building the knowledge base required to design chitosan-based NPs to be used efficiently and specifically.
Assuntos
Quitosana/química , Lisossomos/química , Nanopartículas/química , Transporte Biológico , Células Cultivadas , Físico-Química , Quitosana/metabolismo , Humanos , Lisossomos/metabolismo , Tamanho da Partícula , Eletricidade Estática , Propriedades de SuperfícieRESUMO
Aiming to enhance the immunogenicity of H5N1 split vaccine, the development of a novel antigen delivery system based on quaternized chitosan hydrogel microparticles (Gel MPs) with multiple mechanisms of immunity enhancement is attempted. Gel MPs based on ionic cross-linking are prepared in a simple and mild way. Gel MPs are superior as a vaccine delivery system due to their ability to: 1) enhance cellular uptake and endosomal escape of antigens in dendritic cells (DCs); 2) significantly activate DCs; 3) form an antigen depot and recruit immunity cells to improve antigen capture. Further in vivo investigation shows that Gel MPs, in comparison to aluminum salts (Alum), LPS, and covalent cross-linking quaternized chitosan MPs (GC MPs), induce higher humoral and cellular immune responses with a mixed Th1/Th2 immunity. In conclusion, these results demonstrate that Gel MPs are efficient antigen delivery vehicles based on multiple mechanisms to enhance both humoral and cellular immune responses against H5N1 split antigen.
Assuntos
Sistemas de Liberação de Medicamentos , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Quitosana/química , Eritrócitos/patologia , Hemólise , Humanos , Hidrogéis/química , Vacinas contra Influenza/química , Vacinas contra Influenza/farmacocinética , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , OvinosRESUMO
Clinical applications of siRNA are being hindered by poor intracellular uptake and enzymatic degradation. To address these problems, we devised an oral delivery system for telomerase reverse transcriptase siRNA using N-((2-hydroxy-3-trimethylammonium) propyl) chitosan chloride (HTCC) nanoparticles (HNP). Both the porous structure and the positive charge of HNP facilitated siRNA encapsulation. The outer coating of HTCC not only protected siRNA from enzymatic degradation, but also improved siRNA permeability in intestine tract. In vivo and in vitro experiments proved that HNP could effectively deliver siRNA to lesion site and further into tumor cells. On the basis of confirming the antitumor activity of HNP:siRNA, we continued to encapsulate a hydrophobic chemotherapeutic drug-paclitaxel (PTX) into HNP to form a "two-in-one" nano-complex (HNP:siRNA/PTX). We demonstrated that HNP:siRNA/PTX could simultaneously ferry siRNA and PTX into tumor cells and increase drug concentration, which, in particular, was much more effective in tumor suppression than that of traditional cocktail therapy. These results suggested that the HNP, as a powerful delivery system for both siRNA and chemotherapeutic drug, would have a far-reaching application in human cancer therapy.
Assuntos
Quitosana/análogos & derivados , Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Nanopartículas/química , Neoplasias/tratamento farmacológico , Paclitaxel/uso terapêutico , Compostos de Amônio Quaternário/química , RNA Interferente Pequeno/administração & dosagem , Absorção/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Células CACO-2 , Carbocianinas , Carcinoma Pulmonar de Lewis , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quitosana/química , Endocitose/efeitos dos fármacos , Citometria de Fluxo , Inativação Gênica/efeitos dos fármacos , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Masculino , Camundongos , Nanopartículas/ultraestrutura , Neoplasias/patologia , Paclitaxel/administração & dosagem , Paclitaxel/farmacologia , Permeabilidade/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Telomerase/metabolismo , Distribuição Tecidual/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Whole cell tumor vaccine (WCTV), as a potential treatment modality, elicits limited immune responses because of the poor immunogenicity. To address this issue, researchers have attempted to transduce a cytokine adjuvant into tumor cells, but these single-adjuvant WCTVs curtail the high expectations. In present study, we constructed a multi-adjuvant WCTV based on the nanoparticles modified with cell penetrating peptide, which could facilitate the transportation of granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin 2 (IL-2) into tumor cells. After inactivation, as-designed multi-adjuvant WCTV exhibited programmed promotions on DC recruitment, antigen presentation, and T-cell activation. In vivo evaluations demonstrated the satisfactory effects on tumor growth suppression, metastasis inhibition, and recurrence prevention. Therefore, the nanoparticles-based multi-adjuvant WCTV may serve as a high-performance treatment for anti-tumor immunotherapy.
Assuntos
Vacinas Anticâncer/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Imunoterapia/métodos , Interleucina-2/uso terapêutico , Nanopartículas/química , Animais , Linhagem Celular Tumoral , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Humanos , Interleucina-2/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/administração & dosagem , Distribuição AleatóriaRESUMO
AIM: Low solubility in water has become an intrinsic property of many anticancer drugs, which poses a hurdle in the translation from the bench to the clinic. In this study, we developed a facile method to prepare 10-hydroxycamptothecin (HCPT) nanocrystallites and testified their feasibility for liver-targeting therapy. MATERIALS & METHODS: HCPT nanocrystallites were prepared under the soft template effect of galactosylated chitosan. The internalization profile, intracellular trafficking, drug activity and cell viability were evaluated by exposing these nanocrystallites to human hepatocellular carcinoma HepG2 cells. RESULTS: Galactosylated chitosan located on the HCPT nanocrystallites not only stabilized the formulation in aqueous medium, but also enhanced the cellular internalization through an asialoglycoprotein receptor-mediated pathway. These nanocrystallites also exhibited the advantages of nuclear entry and active HCPT delivery, and consequently better anticancer cytotoxicity could be achieved. CONCLUSION: These data strongly support the superior properties of galactosylated HCPT nanocrystallites on liver-targeting therapy.