Polymer-Encapsulated Aβ Peptide Fragments as an Oligomeric-Specific Vaccine for Alzheimer's Disease

Nanomedicine and versatile therapies for cancer treatment

The higher prevalence of cancer is related to high rates of mortality and morbidity worldwide. By virtue of the properties of matter at the nanoscale, nanomedicine is proven to be a powerful tool to develop innovative drug carriers with greater efficacies and fewer side effects than conventional therapies. In this review, different nanocarriers for controlled drug release and their routes of administration have been discussed in detail, especially for cancer treatment. Special emphasis has been given on the design of drug delivery vehicles for sustained release and specific application methods for targeted delivery to the affected areas. Different polymeric vehicles designed for the delivery of chemotherapeutics have been discussed, including graft copolymers, liposomes, hydrogels, dendrimers, micelles, and nanoparticles. Furthermore, the effect of dimensional properties on chemotherapy is vividly described. Another integral section of the review focuses on the modes of administration of nanomedicines and emerging therapies, such as photothermal, photodynamic, immunotherapy, chemodynamic, and gas therapy, for cancer treatment. The properties, therapeutic value, advantages, and limitations of these nanomedicines are highlighted, with a focus on their increased performance versus conventional molecular anticancer therapies.

Directing the nanoparticle formation by the combination with small molecular assembly and polymeric assembly for topical suppression of ocular inflammation

In this paper, we presented a simple yet versatile strategy to generate a high drug payload nanoparticles by the combination with small molecular assembly and polymeric assembly for topical suppression of ocular inflammation. Upon physical mixing of the succinated triamcinolone acetonide (TA-SA) supramolecular hydrogel with the poly (ethylene glycol)-poly (ɛ-caprolactone)-poly (ethylene glycol) (PECE) aqueous solution at 37 °C, TA-SA/PECE nanoparticles formed spontaneously and characterized thoroughly by transmission electron microscopy (TEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The formed TA-SA/PECE nanoparticles displayed a comparable in vitro anti-inflammatory efficacy to that of native triamcinolone acetonide (TA), through a significant downregulation of various proinflammatory cytokines levels (e.g., NO, TNF-α) in a lipopolysaccharide (LPS) actived RAW264.7 macrophage. Meanwhile, the enhanced transcorneal drug permeability of TA-SA/PECE nanoparticles over that of TA suspension was clearly observed in an isolated rabbit cornea. Intraocular biocompatibility test demonstrated that TA-SA/PECE nanoparticles presented good biocompatibility after topical instillation during entire study period. More importantly, the TA-SA/PECE nanoparticles displayed superior therapeutic efficacy over that of the TA suspension in the endotoxin-induced uveitis (EIU) rabbit model via decreasing neutrophil infiltration in anterior chamber. Overall, the proposed TA-SA/PECE nanoparticles might be a promising candidate for uveitis therapy.

Vaccination with a Novel Antigen-Specific Tolerizing DNA Vaccine Encoding CCOL2A1 Protects Rats from Experimental Rheumatoid Arthritis

Antigen-specific tolerizing DNA vaccines are one of the most promising strategies for rheumatoid arthritis (RA) treatment. They act by inducing potent immune tolerance instead of generalized immunosuppression. Recently, we developed a novel antigen-specific tolerizing DNA vaccine pcDNA-CCOL2A1 coding for chicken type II collagen (CCII) and confirmed its potent therapeutic efficacy in an established rat model of collagen-induced arthritis (CIA). Here we report the prophylactic vaccination efficacy of a single 300 μg/kg dose of pcDNA-CCOL2A1 against CIA incidence, severity, and onset. CCOL2A1 transcripts were detected in the blood of CIA rats 14-42 days after intramuscular injection by 300 μg/kg pcDNA-CCOL2A1. The expression of CCOL2A1 transcripts increased quickly on day 21, peaked at day 28, and then gradually decreased thereafter. Importantly, a single prophylactic vaccination of pcDNA-CCOL2A1 14 days before CIA establishment significantly reduced CIA incidence and severity, deferred its onset, and was as efficacious as the current gold standard drug, methotrexate. The marked effects on CIA incidence and severity closely corresponded to the expression of CCOL2A1. Furthermore, prophylactic vaccination with pcDNA-CCOL2A1 markedly decreased serum content of anti-type II collagen (CII) immunoglobulin G (IgG) antibodies, induced Th1-to-Th2 and Tc1-to-Tc2 shifts, and decreased the percentages of CD4⁺CD29⁺ and Th17 T cells. Prophylactic vaccination with pcDNA-CCOL2A1 also downregulated various Th1 cytokines, while upregulating both the Th2-type cytokine interleukin-10 and the Th3-type cytokine transforming growth factor β. Our results indicate that the pcDNA-CCOL2A1 DNA vaccine acts as a highly efficient inducer of specific immunotolerance that could be a promising option for RA treatment in the near future.

Size-dependent penetration of nanoemulsions into epidermis and hair follicles: implications for transdermal delivery and immunization

Nanoemulsions have been widely applied to dermal and transdermal drug delivery. However, whether and to what depth the integral nanoemulsions can permeate into the skin is not fully understood. In this study, an environment-responsive dye, P4, was loaded into nanoemulsions to track the transdermal translocation of the nanocarriers, while coumarin-6 was embedded to represent the cargoes. Particle size has great effects on the transdermal transportation of nanoemulsions. Integral nanoemulsions with particle size of 80 nm can diffuse into but not penetrate the viable epidermis. Instead, these nanoemulsions can efficiently fill the whole hair follicle canals and reach as deep as 588 μm underneath the dermal surfaces. The cargos are released from the nanoemulsions and diffuse into the surrounding dermal tissues. On the contrary, big nanoemulsions, with mean particle size of 500 nm, cannot penetrate the stratum corneum and can only migrate along the hair follicle canals. Nanoemulsions with median size, e.g. 200 nm, show moderate transdermal permeation effects among the three-size nanoemulsions. In addition, colocalization between nanoemulsions and immunofluorescence labeled antigen-presenting cells was observed in the epidermis and the hair follicles, implying possible capture of nanoemulsions by these cells. In conclusion, nanoemulsions are advantageous for transdermal delivery and potential in transcutaneous immunization.