Scheme of the procedure followed to generate F27-RL and F11-DL.

<p>The general structure of the genomic RNAs used for retrovolution is given at the top, on the left for the F16 population and on the right for the population containing only the G12 variant. The procedure has been previously described [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0140741#pone.0140741.ref034" target="_blank">34</a>] and consists in the repeated transduction of HEK 293T cells with the lentiviral vectors followed by the selection, with puromycin, of cell populations that have stably integrated the proviral DNA that has been produced by reverse transcription. Transfection of this population with the transcomplementation plasmids pHCMV-G and pCMV∆8.91 (see main text) allows the production of the next vector generation that is then used to transduce fresh HEK 293T cells during repeated cycles of selection, transfection and transduction. For screening purposes, target cells are transduced by less than one lentivector particle per cell, and individual clones were isolated in the presence of puromycin. Screening for sensitisation to various compounds is carried out as described in the main text.