Second-Generation Polyamidoamine Dendrimer Conjugated with Oligopeptides Can Enhance Plasmid DNA Delivery In Vitro

Strategies for Improved pDNA Loading and Protection Using Cationic and Neutral LNPs with Industrial Scalability Potential Using Microfluidic Technology

Purpose

In recent years, microfluidic technologies have become mainstream in producing gene therapy nanomedicines (NMeds) following the Covid-19 vaccine; however, extensive optimizations are needed for each NMed type and genetic material. This article strives to improve LNPs for pDNA loading, protection, and delivery, while minimizing toxicity.

Methods

The microfluidic technique was optimized to form cationic or neutral LNPs to load pDNA. Classical "post-formulation" DNA addition vs "pre" addition in the aqueous phase were compared. All formulations were characterized (size, homogeneity, zeta potential, morphology, weight yield, and stability), then tested for loading efficiency, nuclease protection, toxicity, and cell uptake.

Results

Optimized LNPs formulated with DPPC: Chol:DOTAP 1:1:0.1 molar ratio and 10 µg of DOPE-Rhod, had a size of 160 nm and good homogeneity. The chemico-physical characteristics of cationic LNPs worsened when adding 15 µg/mL of pDNA with the "post" method, while maintaining their characteristics up to 100 µg/mL of pDNA with the "pre" addition remaining stable for 30 days. Interestingly, neutral LNPs formulated with the same method loaded up to 50% of the DNA. Both particles could protect the DNA from nucleases even after one month of storage, and low cell toxicity was found up to 40 µg/mL LNPs. Cell uptake occurred within 2 hours for both formulations with the DNA intact in the cytoplasm, outside of the lysosomes.

Conclusion

In this study, the upcoming microfluidic technique was applied to two strategies to generate pDNA-LNPs. Cationic LNPs could load 10x the amount of DNA as the classical approach, while neutral LNPs, which also loaded and protected DNA, showed lower toxicity and good DNA protection. This is a big step forward at minimizing doses and toxicity of LNP-based gene therapy.

Guanidinium-based Integrated Peptide Dendrimers: Pioneer Nanocarrier in Cancer Therapy

The landscape of cancer therapy has witnessed a paradigm shift with the emergence of innovative delivery systems, and Guanidinium-based Peptide Dendrimers have emerged as a vanguard in this transformative journey. With their unique molecular architecture and intrinsic biocompatibility, these dendrimers offer a promising avenue for the targeted delivery of therapeutic cargo in cancer treatment. This comprehensive review delves into the intricate world of Guanidinium- based Peptide Dendrimers, unraveling their structural intricacies, mechanisms of action, and advancements that have propelled them from laboratory curiosities to potential clinical champions. Exploiting the potent properties of guanidinium, these dendrimers exhibit unparalleled precision in encapsulating and transporting diverse cargo molecules, ranging from conventional chemotherapeutics to cutting-edge nucleic acids. The review navigates the depths of their design principles, investigating their prowess in traversing the complex terrain of cellular barriers for optimal cargo delivery. Moreover, it delves into emerging trends, such as personalized therapeutic approaches, multimodal imaging, and bioinformatics-driven design, highlighting their potential to redefine the future of cancer therapy. Crucially, the review addresses the pivotal concerns of biocompatibility and safety, examining cytotoxicity profiles, immune responses, and in vivo studies. It underscores the importance of aligning scientific marvels with the stringent demands of clinical applications. Through each section, the narrative underscores the promises and possibilities that Guanidinium-based Peptide Dendrimers hold and how they can potentially reshape the landscape of precision cancer therapy.

Silk Fibroin-Modified Liposome/Gene Editing System Knocks out the PLK1 Gene to Suppress the Growth of Lung Cancer Cells

Polo-like protein kinase 1 (PLK1) plays a key role in lung cancer cell mitosis. The knockout of PLK1 gene by the CRISPR-Cas9 system can effectively inhibit the proliferation of tumor cells, but there is no suitable vector for in vivo delivery. In this study, CRISPR-Cas9 gene knockout plasmids encoding sgRNA, Cas9 and green fluorescent protein were constructed. Then, the plasmids were packaged with liposome (Lip) and cholesterol-modified Antheraea pernyi silk fibroin (CASF) to obtain the CASF/Lip/pDNA ternary complex. The CASF/Lip/pDNA complex was transfected into lung cancer cells A549 to investigate the transfection efficiency, the PLK1 gene knockout effect and the inhibitory effect on lung cancer cells. The results showed that the transfection efficiency of the CASF/Lip/pDNA complex was significantly higher than that of the Lip/pDNA binary complex, and the expression of PLK1 in cells transfected with CASF/Lip/pDNA complexes was significantly lower than that in cells transfected with Lip/pDNA complexes. The CASF/Lip/pDNA complex significantly increased the apoptosis rate and decreased the proliferation activity of lung cancer cells compared with Lip/pDNA complexes. The cytotoxicity of the complexes was evaluated by coculture with the human bronchial epithelial cells BEAS2B. The results showed that CASF/Lip/pDNA complexes exhibited lower cytotoxicity than Lip/pDNA complexes. The fibroin-modified liposome/PLK1 gene knockout system not only effectively inhibited the growth of lung cancer cells but also showed no obvious toxicity to normal cells, showing potential for clinical application in lung cancer therapy.