Functional characterization studies of the human genome have delivered a tremendous amount of information through using genome-based loss-of-function screening in diverse models. RNA interference (RNAi) has been used as the predominant method for loss-of-function of genome screening, but it is limited by variable efficiency, frequent incompleteness of protein depletion and confounding off-target effects. CRISPR/Cas9 technology is ideally suited for genome‐wide screening applications due to the ease of generating guide RNAs (gRNAs) and the versatility of Cas9 or Cas9 derivatives to knockout, repress, or activate expression of target genes. However, certain types of mammalian cells are difficult to transfect using lipid reagents or electroporation. In order to circumvent these difficulties, lentiviral vectors are commonly used as another delivery method as they can be easily titrated to manipulate transgene copy number and are stably maintained by integration into the genomic DNA during subsequent cell replication.

As one of the pioneers in creating libraries, Creative Biogene has developed a proficiency in producing high-quality libraries expressing short genetic elements, such as peptides, shRNA, enzyme active site elements, and sgRNA. Our QVirus™ platform can offer the packaging of your CRISPR libraries into our lentiviral vectors. CRISPR lentiviral libraries are packaged into highly pure and concentrated lentiviral particles, either from an existing lentiviral plasmid library or from a custom plasmid library that we construct starting from a provided oligonucleotide pool, corresponding to your guide sequences.