Summary of clinical characteristics of patients
| COVID-19 | Controls# | Non-COVID-19 pneumonia#,¶ | |
| Participants | 11 | 25 | 18 |
| Male/female | 8/3 | 17/8 | 10/8 |
| Age (years) | 71±5 | 70±2 | 75±1 |
| Smokers (current or ex-smokers) | 3 | 25 | 18 |
| Acute pneumonia | 11 | 0 | 18 |
| Comorbidities | |||
| COPD | 4 | 14 | 0 |
| Cardiovascular disease+ | 7 | 9 | 18 |
| Diabetes | 4 | 2 | 8 |
| Chronic kidney disease | 2 | 0 | 1 |
| Malignancy | 2 (lymphoma, brain tumour) | 25 (lung cancer) | 0 |
Data are presented as n or mean±sem. COVID-19: coronavirus disease 2019. #: all non-COVID-19 samples were obtained from distal lung tissue to resected lung carcinoma (lobectomy or pneumonectomy); ¶: all non-COVID-19 acute pneumonia samples were from patients with aspiration pneumonia; +: includes ischaemic heart disease, hypertension, cardiomyopathy, pulmonary embolism, peripheral artery disease and stroke.