<p>Evidence Supporting the Safety of Pegylated Diethylaminoethyl-Chitosan Polymer as a Nanovector for Gene Therapy Applications</p>

Abstract

Purpose: Diethylaminoethyl-chitosan (DEAE-CH) is a derivative with excellent potential as a delivery vector for gene therapy applications. The aim of this study is to evaluate its toxicological profile for potential future clinical applications. Methods: An endotoxin-free chitosan (CH) modified with DEAE, folic acid (FA) and polyethylene glycol (PEG) was used to complex small interfering RNA (siRNA) and form nanoparticles (DEAE 12-CH-PEG-FA 2 /siRNA). Based on the guidelines from the International Organization for Standardization (ISO), the American Society for Testing and Materials (ASTM), and the Nanotechnology Characterization Laboratory (NCL), we evaluated the effects of the interaction between these nanoparticles and blood components. In vitro screening assays such as hemolysis, hemagglutination, complement activation, platelet aggregation, coagulation times, cytokine production, and reactive species, such as nitric oxide (NO) and reactive oxygen species (ROS), were performed on erythrocytes, plasma, platelets, peripheral blood mononuclear cells (PBMC) and Raw 264.7 macrophages. Moreover, MTS and LDH assays on Raw 264.7 macrophages, PBMC and MG-63 cells were performed. Results: Our results show that a targeted theoretical plasma concentration (TPC) of DEAE 12-CH-PEG-FA 2 /siRNA nanoparticles falls within the guidelines' thresholds: <1% hemolysis, 2.9% platelet aggregation, no complement activation, and no effect on coagulation times. ROS and NO production levels were comparable to controls. Cytokine secretion (TNF-α, IL-6, IL-4, and IL-10) was not affected by nanoparticles except for IL-1β and IL-8. Nanoparticles showed a slight agglutination. Cell viability was >70% for TPC in all cell types, although LDH levels were statistically significant in Raw 264.7 macrophages and PBMC after 24 and 48 h of incubation. Conclusion: These DEAE 12-CH-PEG-FA 2 /siRNA nanoparticles fulfill the existing ISO, ASTM and NCL guidelines' threshold criteria, and their low toxicity and blood biocompatibility warrant further investigation for potential clinical applications.

Visualizing the Potential Impairment of Polymyxin B to Central Nervous System Through MR Susceptibility-Weighted Imaging

“…As shown in Figure 2D , the pure water and the 1 × PBS solutions were set as the positive control and negative controls with 100 and 0% hemolysis rate, respectively. With respect to the Fe 3 O 4 nanoparticles 1 × PBS solution, the calculated hemolysis rates were less than 1% at the Fe concentration of particles ranging from 0.01 to 10 mM, which significantly lower than the threshold that the hemolysis rate should be lower than 5% specified in the International Organization for Standardization (ISO) and the American Society for Testing and Materials (ASTM) ( Rondon et al, 2020 ). These results further showed the biosafety and the blood compatibility of Fe 3 O 4 nanoparticles in the blood stream, providing a prerequisite for the intravenous injection of the nanoparticles.…”

An inflammation-targeted nanoparticle with bacteria forced release of polymyxin B for pneumonia therapy

“…These rates are lower than the threshold hemolysis rate of 5% set by the International Organization for Standardization and the American Society for Testing and Materials. 43 In significant contrast, free PMB exhibited a considerable hemolytic toxicity even at the low concentration of 32 µg mL −1 , with the hemolysis rates of 7.55%. These results provided a prerequisite indication of safety for the further intravenous injection of the nanoparticles.…”

Improving Polysaccharide-Based Chitin/Chitosan-Aerogel Materials by Learning from Genetics and Molecular Biology

“…In summary, films, beads, fibers, intragastric floating tablets, microspheres, and chitin/chitosan nanoparticles and their derivatives have been formulated for use in the pharmaceutical field. Recent findings even support their potential for gene therapy applications [ 7 , 40 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 ].…”

“…This increases the solubility of chitosan and usually occurs in acidic environments [ 38 ]. Because of the positive charge, chitosan can form complexes with numerous negatively charged molecules, such as growth factors, nucleic acids, and cytokines [ 39 , 40 , 41 ]. Thus, chitin/chitosan matrices recruit bioactive factors from the environment, protect their degradation and increase local efficacy [ 36 ].…”