Figure 8.
Genotoxicity
Vector insertions in tumors or tissues (A) and IVIM assay (B). (A) Vector genomic insertions were analyzed in BM, spleen, and thymus of mice bearing tumors containing EF1a-hArtemis-LV-transduced donor cells. The read counts are indicated in each sample analyzed, and the percentage of reads for each IS is represented by individual colors, with gray representing IS with less than 3% of relative abundance. Samples are identified by mouse number and tissue (BM=bone marrow), SPL (spleen) and THY (thymus). (B) Insertional mutagenesis leads to clonal outgrowth after low-density seeding in the IVIM assay. Non-immortalized cells do not grow (negative, below limit of detection [LOD]). The number of wells containing insertion mutants is used to calculate the replating frequency (RF) according to Poisson statistics. Assays with an RF ≥ 3.17 × 10−4 (Q1 level) are counted as positive. Each dot represents one assay. In the three experiments, we obtained immortalized clones from the cells transduced by the positive control vectors RSF91 or LV-SF, whereas all plates containing EF1a-Artemis transduced cells were below the Q1 level. Horizontal bars represent mean values.