 (A) GSK716 was added to CHO-TET-ON-Z-A1AT cells (Ordóñez et al., 2013) with simultaneous induction of Z α1-antitrypsin expression using doxycycline, and polymer load was quantified with the 2C1 monoclonal antibody that is specific to pathological polymers of α1-antitrypsin (Miranda et al., 2010). The parent cell line that did not express Z α1-antitrypsin provided a negative control. GSK716 completely prevented intracellular polymer formation. Scale bar: 50 µm. (B) Quantification of immunostained CHO-TET-ON-Z-A1AT cells showed that GSK716 reduced intracellular polymer formation and increased the secretion of Z α1-antitrypsin in a dose-dependent manner with similar potencies. Data were normalised to vehicle and a control compound from the GSK716 series at saturating concentration. Data presented as mean ± SD, n = 61 (secretion) and n = 67 (polymer inhibition) 