<p>In connection with the optimisation of prime editing with regard to the F508del mutation, it was necessary to compare different pegRNAs, as their optimal structure always depends on the application context. We therefore designed and cloned 14 variants of pegRNAs for the target of the reporter system and then tested them on the reporter system using the PE2 system. </p>
<p>For pegRNA screening, we co-transfected the HEK293 cells with our modified reporter plasmid, the pegRNA expressing plasmid and pCMV-PE2. We were then able to measure the fluorescence after 72 hours using FACS and evaluate which pegRNA showed the highest efficiency. </p>
<figcaption><b>Figure 9.</b>Percentage of fluorescent HEK293 cells 72 h after transfection with various pegRNAs (pegRNA1-14) normalized to pDAS12124 pre-edited as internal positive control as result of flow cytometry analysis.</figcaption>
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<p>We also co-transfected the CFBE41o- with our modified reporter plasmid, the plasmid expressing pegRNA04 as well as pCMV-PE6c. As a result, we observed fluorescence, indicating successful editing of the reporter plasmid. The negative controls transfected with only one of the plasmids each showed no fluorescence, routing out other factors. This gave us validation, that our pegRNAs work not only in HEK, but also in epithelial cells that express CFTR F508del. </p>
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description="Microscopy results after 24h or 48h. Transfection of pDAS12124-preedited with lipofectamine 3000 was successfully done in CFBE41o- cell line and visible after 48h. CFBE41o- cell line was transfected with pDAS-IDT with Lipofectamine 3000 and afterwards with LNPs including PE6c and pegRNA4 and was after 24h fluorescence visible."
