Recent developments of polymeric delivery systems in gene therapeutics

Gene therapy has achieved remarkable results in treating diseases by transmitting exogenous functional genes to target cells, inducing gene silencing, gene expression, and gene editing. However, nucleic acids are susceptible to degradation by nucleic acid endonucleases and clearance by the immune system. Therefore, safe and efficient gene delivery vectors are needed to facilitate gene therapy's clinical implementation further. Although viral vectors exhibit high transfection efficiency, their safety issues limit their further application. Despite their promising clinical performance, lipid nanoparticles suffer from poor stability and difficult storage. Polymer cationic vectors (PCVs) with low cost, low immunogenicity, and tunability have attracted the attention of scientists. This article reviews the main strategies to improve the gene transfection efficiency of polymeric delivery systems in recent years and their applications in certain diseases. However, there are still challenges in gene delivery with polymer vectors. Hence, the paper concludes with an outlook on the future development of PCVs, which will hopefully help in the design of PCVs. A brief overview of main strategies to improve the gene transfection efficiency of PCVs recently and their applications in certain diseases.