Table 2 Some current delivery systems for the CRISPR-Cas system
Delivery system | Type of CRISPR-Cas system | Experimental model | Effects and comments | Ref. |
|---|---|---|---|---|
AAVs | Cpf1 | Primary human hepatocytes | The mutation rates were estimated at around 12% of insertion/deletion (indel), with transduced human hepatocytes at 2 weeks after transduction | [111] |
Baculovirus | dCas9-VPR and gRNA | Rat adipose stem cells | Successfully induced gene transfection and achieved efficient gene editing | [112] |
Dendrimers | Cas9 mRNA, sgRNA, and donor DNA | HEK293 B/GFP cells | By optimizing the system for simultaneous delivery of Cas9 mRNA, sgRNA, and donor DNA, the delivery system via dendritic lipid nanoparticles enables editing of more than 91% of cells, achieving integrated, concise, and efficient gene editing | [113] |
Cas9 RNP | 293 T cells | Owing to the presence of boric acid, the vectors can bind to differently charged proteins simultaneously, effectively maintaining the activity of the delivered Cas9 and enabling efficient CRISPR-Cas9 editing | [114] | |
Lipid nanoparticles | Cas9 mRNA and sgRNAs | HEK293/GFP cells | The LNPs enabled up to ~ 80% gene editing in vivo | [115] |
Cas9 mRNA and sgRNA | Duchenne muscular dystrophy mice model | The LNPs induces stable genomic exon skipping and have shown promising therapeutic effects in mice. In addition, LNPs can target multiple muscle groups and are characterized by repeated administration and low immunogenicity | [116] | |
Micelles | Cas9 mRNA and sgRNA | Parenchymal cells in the mouse brain | Co-encapsulation of sgRNA with Cas9 mRNA in micelles prevents release of sgRNA upon dilution, thereby increasing the tolerance of sgRNA to enzymatic degradation | [117] |