Differential DAMP release was observed in the sputum of COPD, asthma and asthma-COPD overlap (ACO) patients.
Huang. Xiaolin X; Tan. Xiaoyu X; Liang. Yue Y; Hou. Changchun C; Qu. Dongming D; Li. Mengze M; Huang. Qinghua Q
Key Findings
- LL‑37 levels in sputum are elevated in ACO compared to healthy smokers and never‑smokers.
- LL‑37 is higher in ACO than in asthma, but lower than in COPD.
- Sputum LL‑37 shows good ability (high AUC) to differentiate asthma from COPD in ROC analysis.
Practical Outcomes
- For biohackers, the main takeaway is that LL‑37 is currently useful as a biomarker for distinguishing lung disease subtypes, not as a direct intervention. There is no evidence here that taking LL‑37 will improve lung health, so it doesn’t suggest a new supplement protocol or dosage. The findings may inform future diagnostic tools, but they have limited immediate actionable value for self‑directed health optimization.
Summary
The study measured several immune‑activating proteins (including the antimicrobial peptide LL‑37) in the sputum of people with asthma, COPD, and the mixed condition asthma‑COPD overlap (ACO). It found that LL‑37 levels are higher in ACO than in asthma but lower than in COPD, and that LL‑37 can help tell asthma from COPD in a lab test. The work is mainly about using LL‑37 as a diagnostic marker, not about taking it as a supplement or therapy.
Abstract
Asthma-COPD overlap (ACO) has been under intensive focus; however, the levels of damage-associated molecular patterns (DAMPs) that can activate the innate and adaptive immune responses of ACO are unknown. The present study aimed to examine the levels of some DAMPs in asthma, COPD, and ACO and to identify the associations between clinical characteristics and DAMPs in ACO. Sputum from subjects with asthma (n = 87) or COPD (n = 73) and ACO (n = 68) or from smokers (n = 62) and never-smokers (n = 62) was analyzed for high mobility group protein B1 (HMGB1), heat shock protein 70 (HSP70), LL-37, S100A8, and galectin-3 (Gal-3). The concentration of HMGB1, HSP70, LL-37, and S100A8 proteins in sputum from ACO patients was significantly elevated, whereas that of Gal-3 was reduced, compared to that of smokers and never-smokers. The levels of HMGB1 and Gal-3 proteins in ACO patients were elevated compared to those in asthma patients. The sputum from ACO patients showed an increase in the levels of LL-37 and S100A8 proteins compared to that of asthma patients, whereas the levels decreased compared to those of COPD patients. The concentrations of HMGB1, HSP70, LL-37, and S100A8 proteins in the sputum of 352 participants were negatively correlated, whereas the levels of Gal-3 were positively correlated, with FEV1, FEV1%pred, and FEV1/FVC. Sputum HMGB1 had a high AUC of the ROC curve while distinguishing ACO patients from asthma patients. Meanwhile, sputum LL-37 had a high AUC of the ROC curve in differentiating asthma and COPD. The release of sputum DAMPs in ACO may be involved in chronic airway inflammation in ACO; the sputum HMGB1 level might serve as a valuable biomarker for distinguishing ACO from asthma, and the sputum LL-37 level might be a biomarker for differentiating asthma and COPD.
Study Information
pubmed
2019
2019-12-17T00:00:00.000Z
10.1038/s41598-019-55502-2
31
37