FIGURE 1.

In vivo efficacy of ND-L02-s0201 in bleomycin (BLM)-induced chronic lung fibrosis model in rats. a) Model illustration. Male Sprague-Dawley rats were treated with BLM eight times at 3 mg·kg⁻¹ (Day 0, 14) and 1 mg·kg⁻¹ (Day 1 to Day 6) (0.5 mL·kg⁻¹) to induce chronic lung damage. ND-L02-s0201 was dosed i.v. with initial dose of 2 mg·kg⁻¹ on Day 18 and weekly follow-up doses at 0.5, 1,1.5, 2 mg·kg⁻¹ for another 4 weeks. Two control groups were included for comparisons: 1) animals not treated with BLM or siRNA formulation (Sham, n=8); 2) animals induced with BLM but not treated with siRNA formulation (Vehicle, n=12). b) Relative lung weight. Three days after last dose of siRNA treatment, lungs were harvested and weighed during necropsy and relative lung weights were calculated based on the body weight of each animal on necropsy day. c) Lung hydroxyproline content. A section of the right lung lobe from each animal was collected and stored at −80°C until tissue lysis for hydroxyproline quantification. d and e) Histopathology evaluation. The left lung was perfused and inflated and fixed for tissue section and haematoxylin and eosin (H&E) and trichrome staining. Histological findings were assigned a semiquantitative severity score based on the following system: minimal=1, mild=2, moderate=3 and marked=4, either independent score of trichrome stain (d) or sum of a panel of parameters of H&E stain (e) (refer to Materials and Methods, Histopathology section for details). f) Representative images (trichrome stain) following ND-L02-s0201 treatment (2 mg·kg⁻¹·week⁻¹, 4 weeks) in BLM rat lung. g) Downregulation of target gene HSP47 following ND-L02-s0201 treatment. h) Representative Q-PCR results from rat Fibrosis RT2 Profiler PCR Arrays (Qiagen) consisting of a panel of 84 key genes involved in fibrosis. 2 × 5: 2 mg·kg⁻¹ for 5 weeks; 2 + 1.5 × 4: 2 mg·kg⁻¹ initial then 1.5 mg·kg⁻¹ for 4 weeks; 2 + 1 × 4: 2 mg·kg⁻¹ initial then 1 mg·kg⁻¹ for 4 weeks; 2 + 0.5 × 4: 2 mg·kg⁻¹ initial then 0.5 mg·kg⁻¹ for 4 weeks. **: p<0.01; ***: p<0.001.