CRISPR/Cas9-mediated site-specific insertion of exogenous genes holds potential for clinical applications.However,it is still infeasible because homologous recombination(HR)is inefficient,especially for nondividing ce...CRISPR/Cas9-mediated site-specific insertion of exogenous genes holds potential for clinical applications.However,it is still infeasible because homologous recombination(HR)is inefficient,especially for nondividing cells.To overcome the challenge,we report that a homology-independent targeted integration(HITI)strategy is used for permanent integration of high-specificity-activity Factor IX variant(F9 Padua,R338L)at the albumin(Alb)locus in a novel hemophilia B(HB)rat model.The knock-in efficiency reaches 3.66%,as determined by droplet digital PCR(dd PCR).The clotting time is reduced to a normal level four weeks after treatment,and the circulating factor IX(FIX)level is gradually increased up to 52%of the normal level over nine months even after partial hepatectomy,demonstrating the amelioration of hemophilia.Through primer-extension-mediated sequencing(PEM-seq),no significant off-target effect is detected.This study not only provides a novel model for HB but also identifies a promising therapeutic approach for rare inherited diseases.展开更多
基金supported by grants from National Key R&D Program of China(2019YFA0110802 and 2019YFA0802800)the National Natural Science Foundation of China(32025023,31971366)+1 种基金grants from the Shanghai Municipal Commission for Science and Technology(21CJ1402200,20140900200)the Innovation Program of Shanghai Municipal Education Commission(2019-01-07-00-05-E00054)。
文摘CRISPR/Cas9-mediated site-specific insertion of exogenous genes holds potential for clinical applications.However,it is still infeasible because homologous recombination(HR)is inefficient,especially for nondividing cells.To overcome the challenge,we report that a homology-independent targeted integration(HITI)strategy is used for permanent integration of high-specificity-activity Factor IX variant(F9 Padua,R338L)at the albumin(Alb)locus in a novel hemophilia B(HB)rat model.The knock-in efficiency reaches 3.66%,as determined by droplet digital PCR(dd PCR).The clotting time is reduced to a normal level four weeks after treatment,and the circulating factor IX(FIX)level is gradually increased up to 52%of the normal level over nine months even after partial hepatectomy,demonstrating the amelioration of hemophilia.Through primer-extension-mediated sequencing(PEM-seq),no significant off-target effect is detected.This study not only provides a novel model for HB but also identifies a promising therapeutic approach for rare inherited diseases.
