We assessed the levels of S100A8/A9 (526,600 ± 727,038 pg ml−1, range: 0–3.2 × 106 pg ml−1 in SSc, 42.6 ± 117.5 pg ml−1, range: 0–409.6 pg m−1 in HD) and LL37 (1507 ± 1737 pg ml−1, range: 0–8437 pg ml−1 in SSc, 866.5 ± 666.5 pg ml−1, range: 0–2022 pg ml−1 in HD), as in Supplementary Fig. 3a, c, because both are potential biomarkers in SSc19–21. The gene discussed is S100A8; the disease is systemic sclerosis.