Antimicrobial peptides in lung inflammation.
Beisswenger. Christoph C; Bals. Robert R
Key Findings
- LL‑37 is produced by epithelial cells, neutrophils, lymphocytes, and macrophages in the lung
- Beyond killing microbes, LL‑37 binds to receptors and activates many immune and structural cells
- Levels of LL‑37 in airway secretions change in various pulmonary diseases, indicating a role in disease processes
Practical Outcomes
- Knowing LL‑37’s dual antimicrobial and immune‑modulating actions suggests that strategies to support its natural production (e.g., adequate vitamin D, gut‑lung axis health) might improve lung defenses. However, the abstract does not provide specific dosing or protocols, so biohackers should view this as background knowledge rather than a direct intervention guide.
Summary
LL‑37 is a natural protein made by many cells in the lungs that not only kills germs directly but also talks to other immune cells to shape inflammation. Its levels go up or down in different lung diseases, showing it plays a key role in lung health.
Abstract
Antimicrobial peptides (AMPs) are expressed in the respiratory tract and act as effector substances of the innate immune system. A variety of cells synthesize and secrete AMPs including epithelial and professional host defense cells such as neutrophils, macrophages, and NK cells. In the human lung, beta-defensins originate from epithelial cells, macrophages and lymphocytes. alpha-defensins are synthesized by neutrophils. LL-37/hCAP-18 is produced by epithelial cells, neutrophils, lymphocytes, and macrophages. AMPs act as endogenous antibiotics by direct destruction of microorganisms. Recently, it became clear that AMPs bind to cellular receptors and activate a variety of cell types such as airway epithelial cells, endothelial cells, mast cells, macrophages, dendritic cells, and neutrophils amongst others. Concentrations of AMPs in lung secretions are altered in several pulmonary diseases. This chapter describes the basic and applied biology of AMPs in the human lung and their potential role in pulmonary disease.
Study Information
pubmed
2005
10.1159/000086651
63
112