Fig. 8. DSP expression alters the cellular response to injury.

(A) Cells were plated in 2D and allowed to reach confluence before a scratch wound was made. Wound closure was calculated as a percentage of the initial wound over a 24-hour period. n = 3 experimental replicates of independent wells of a differentiation. (B) Cells were treated with TGF-β1 (1 ng/ml) for 48 hours before collecting RNA, and COL1A1 expression was measured by qRT-PCR. n = 3 experimental replicates of independent wells of a differentiation. (C) Cells were plated at ALI and then exposed to 5% cigarette smoke in a gas phase or humidified air. Cells were collected 2 hours after smoke exposure, and CLDN4, TJP1, and TJP3 were measured by qRT-PCR. n = 3 experimental replicates of independent ALIs of a differentiation. (D) Cells were exposed to 5% cigarette smoke in a gas phase or humidified air while plated at ALI and then replated in 3D Matrigel to reform alveolospheres over 2 weeks. Colony-forming efficiency was calculated relative to air-exposed cells. n = 3 experimental replicates of independent wells of two differentiations. All error bars represent SD. Statistical significance was determined using unpaired, two-tailed Student’s t test or a one-way ANOVA with a Tukey multiple comparison test; *P < 0.05, **P < 0.005, and ***P < 0.001.