Signosis' EL-018 is a stable Ba/F3 cell line expressing EGFR with the M766_A767insAI insertion in the loop following the αC helix of the kinase domain. This exon 20 insertion is associated with variable sensitivity to EGFR TKIs. The line was generated using an MSCV-IRES-EGFP retroviral construct, with GFP for cell selection by FACS. EGFR expression was confirmed via PCR and Western blot.