Fig. 6.

Organoid modeling identifies that IRE1α signaling mediates the reprogrammed cell state. (A) Schematic for organoid experiments using uninduced Sftpc^C121G AEC2s and Sftpc^WT mouse lung fibroblasts with ex vivo induction of the Sftpc mutation using 1 μM 40H-TMX (vehicle = 0.1% EtOH) and treatment with 200 nM OPK-711 or vehicle (0.1% DMSO) for final 96 h of culture. (B) Representative immunostaining of day 14 organoids for SP-C shows presence of proSP-C in 4OH-TMX-treated culture (60× magnification scale bars = 20 μM). (C–G) Sftpc (C), Xbp1 splicing ratio (D), Chop (E), Krt8 (F), and Cldn4 (G) expression measured by qRT-PCR of day 14 organoid culture cells 96 h comparing combined vehicle (0.05% EtOH + 0.1% DMSO) and 4OH-TMX (in 0.05% EtOH) with 0.1% DMSO added to media and 4OH-TMX (0.05% EtOH) + OPK-711 (0.1% DMSO). n = 4 biological replicates. *p < 0.05, **p < 0.005, ***p < 0.0005 by one-way ANOVA with Tukey’s multiple comparisons test.