• Novel nano delivery for CRISPR/Cas system delivery instead of traditional methods
  • Helia Ramezani ,1,* Hanieh Ataollahi,2
    1. Faculty of Biological Science, Department of Biotechnology, Islamic Azad University Tehran North Branch, Tehran, Iran.
    2. Faculty of Biological Science, Department of Biotechnology, Islamic Azad University, North Tehran Branch, Tehran, Iran.


  • Introduction: Introduction: In recent years, clustered regularly interspaced short palindromic repeat (CRISPR) /CRISPR-associated (Cas) genome editing systems have become one of the most powerful platforms for basic biomedical research and therapeutic applications. CRISPR/Cas systems are adaptable immune mechanisms of many bacteria and archaea to protect themselves from invading nucleic acids. Since its first application in mammalian cells in 2013, the CRISPR / Cas system, based on RNA guided nucleases, has revolutionized the way genome editing is done. In previous decades, the generation of disease models was an extremely slow and expensive process, requiring complex manipulation of embryonic stem cells, as well as endless reproduction of mice to achieve the desired phenotype and genotype. However, following the emergence of the CRISPR / Cas9 system, new disease models have been developed with unprecedented speed and precision due to the simplicity and flexibility of these systems. Despite the aforementioned merits, efficient delivery may likely become the main hurdle in the eventual application and clinical translation of the CRISPR/Cas9 system. Currently, the strategies of CRISPR/Cas9 delivery are mainly based on physical approaches (electroporation, microinjection, hydrodynamic injection, etc.) and viral vectors (lentivirus, adenovirus (Ad), adeno-associated virus (AAV), etc.). have achieved successful therapeutic efficacy via precise modification of the genome and exceeded previous genome engineering methods owing to its versatility and simplicity. Rapid expansion in biomedical research has benefited from this newly emerged technique, such as genetic diseases treatment, cancer characterization, and plant improvement. However, the key challenge is the efficient delivery of CRISPR components in vivo and nanotechnology plays an indispensable role in nonviral gene delivery. Polymer polyethylenimine (PEI), a golden standard for gene delivery, was utilized to deliver large-sized plasmids with relatively high efficiency both in vitro and in vivo compared to virus carriers. Moreover, polymer polyethyleneimine-(PC)-cyclodextrin was synthesized to deliver CRISPR/Cas9 plasmid with much lower cytotoxicity compared to PEI 25K.
  • Methods: Method: This study is a review study that conducted in 2021. The data of this study using the keywords “CRISPER/Cas”; “Drug delivery system and CRISPER” at “ScienceDirect”; “PubMed”; “Springer” databases were collected and were analyzed. Articles were opted and were utilized based on their relevance owing to title and abstract.
  • Results: Result: Based on several new methods of CRISPR/Cas system delivery mentioned in the new research, instead of using common delivery systems, they are more operational. These nano-drug delivery systems include different types of polymer nanoparticles, liposomes, gold nanoparticles, conjugated cell-penetrating peptide (CPP) modified nanoparticles, and cell membrane-derived nanoparticles. In addition, it has recently been reported that a new CRISPR/Cas12b system has been developed that can significantly reduce the off-target effects of human genome editing. In addition, Cas9/sgRNA RNP is considered more advantageous because it has higher safety and fewer off-targets compared to the other two delivery methods (CRISPR/Cas9 plasmid or Cas9 mRNA/sgRNA hybrid). Controlling the activity of Cas9 ribonucleoprotein within a specific time window can effectively prevent Cas9 from being overactive, thereby reducing side effects and improving safety.
  • Conclusion: Conclusion: In the future, using new drug delivery systems rather than CRISPR/Cas9 delivery strategies that are mostly dependent on physical approaches will have a privileged role in clinical trhapetics. Furthermore, because of its versatility and simplicity, the genome-editing tool, clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 system, could achieve successful therapeutic efficacy through precise genome modification and outperformed previous genome engineering methods.
  • Keywords: Keywords: CRISPER/Cas9, Nano drug delivery, Genome editing