Group comparison of telomere length and DNA damage in lung tissue
| Controls | TERT-PF | IPF | fHP | |
| Average TL (T/S ratio) of whole biopsy by MMqPCR (IQR) | 0.932# (0.909–0.947) | 0.772¶ (0.734–0.803) | 0.862 (0.810–0.959) | 0.849 (0.778–0.884) |
| AT2 cell | ||||
| γH2AX signal (IQR) | 1005 (246–3354) | 4253+ (3019–6390) | 3923 (2005–5364) | 3661 (2028–4749) |
| FISH TL (IQR) | 1764# (999–2484) | 464¶ (226–703) | 729§ (342–1101) | 1049 (679–1605) |
| Club cell | ||||
| γH2AX signal (IQR) | 1303 (248–3782) | 1879 (902–4624) | 1745 (487–3407) | 6769+ (4025–8827) |
| FISH TL (IQR) | 1650# (769–2600) | 813¶ (467–1147) | 1405 (821–1949) | 1155 (847–1864) |
| Myofibroblast | ||||
| γH2AX signal (IQR) | NA | 752 (0–1637) | 388 (9.2–2691) | 2080 (681–7381) |
| FISH TL (IQR) | NA | 924¶ (646–1345) | 1518 (1139–2105) | 1513 (1055–2069) |
Numbers describe median telomere length or DNA damage signal. TERT-PF: patients with pulmonary fibrosis and a telomerase reverse transcriptase mutation; IPF: idiopathic pulmonary fibrosis; fHP: fibrotic hypersensitivity pneumonitis; AT2: alveolar type 2; TL: telomere length; NA: not applicable. #: telomeres were significantly longer than in the other study groups (p<0.05); ¶: telomeres were significantly shorter than in the other study groups (p<0.05); +: DNA damage signal was significantly higher than in the other study groups (p<0.05); §: telomeres in AT2 cells of IPF lungs were significantly shorter than in AT2 cells of fHP lungs (p<0.0001).