Distinct temporal profiles of AMPs and cytokines in pleural fluids from open and closed thoracic surgeries and exploration of synergy with antibiotics and wound healing effects.

Antimicrobial peptides (AMPs) play a crucial role in immune defense and wound healing. Their expression and function in pleural fluids following different thoracic surgeries remain underexplored. This study aims to compare AMP and cytokine profiles in pleural fluids from patients undergoing open and closed thoracic surgeries and assess their antimicrobial efficacy and wound healing potential. Pleural fluid and blood samples were collected from 24 patients at multiple time points post-surgery. Levels of four AMPs (DEF-1β, Angiogenin, RNase7, LL-37) and five cytokines (IL-1β, IL-2, IL-6, IL-8, TNF-α) were measured. Antimicrobial activity against E. coli and S. aureus was tested, including combinations with cefazolin. Wound healing was assessed using an in vitro scratch assay. DEF-1β was significantly higher in open surgeries, while Angiogenin was elevated in closed surgeries. Pleural fluids exhibited strong antimicrobial activity, enhanced when combined with cefazolin. Wound healing was rapid but transient with open surgery fluids and more sustained with closed surgery fluids. The distinct AMP profiles and synergistic effects with antibiotics suggest that pleural fluid-derived AMPs could enhance postoperative care. Further studies are needed to explore their therapeutic potential.