FIGURE 1.

Cigarette smoke impairs interferon (IFN)-γ and virus-induced upregulation of the immunoproteasome in vitro and ex vivo. a) Immunoproteasome subunits low molecular weight protein (LMP)2 and LMP7 expression in MLE-12 treated with 10% or 25% cigarette smoke extract (CSE) and 75 IU·mL⁻¹ IFN-γ for 24 h. Densitometric analysis of LMP2 and LMP7 expression normalised to β-actin with control set to 1 in IFN-γ-treated cells. b) LMP2 and LMP7 expression in MLE-12 treated with 10% or 25% CSE for 24 h and then electroporated with 1 or 5 μg·mL⁻¹ PolyI:C for 24 h. Densitometric analysis of LMP2 and LMP7 expression normalised to β-actin with PolyI:C only group set to 1. c) LMP2 and LMP7 expression in MLE-12 treated with 10% or 25% CSE for 24 h and then infected with murine γ-herpesvirus (MHV)-68 (multiplicity of infection (MOI) 1) for 48 h. Densitometric analysis of LMP2 and LMP7 expression normalised to β-actin with MHV-68 infection group set to 1. d) LMP2 and LMP7 expression in mouse precision-cut lung slices (PCLS) treated with 10% or 25% CSE and co-cultured with 1 μg·mL⁻¹ PolyI:C for 24 h. Densitometric analysis of LMP2 and LMP7 expression normalised to β-actin with PolyI:C only group set to 1. Data are presented as mean±sem, one-sample t-test; *: p<0.05, **: p<0.01.