The study found that a natural antimicrobial protein called LL‑37 is higher in the fluid around the gums of people with aggressive gum disease, but its level in the blood doesn’t change. This suggests LL‑37 is a local marker of gum damage rather than a systemic factor you can tweak with supplements or drugs.

hCAP18/LL-37 is an endogenous antibiotic having a role in innate immunity. The aim of the present study was to evaluate serum and gingival crevicular fluid (GCF) hCAP18/LL-37 levels in patients with generalized aggressive periodontitis (G-AgP). Twenty-six G-AgP patients, 24 gingivitis patients, and 25 healthy subjects were included in this study. Periodontal parameters including probing depth, clinical attachment level, plaque index, and papilla bleeding index were recorded. GCF and serum hCAP18/LL-37 levels were analyzed by enzyme-linked immunosorbent assay. GCF hCAP18/LL-37 level was significantly higher in G-AgP compared to others (p = 0.038, p < 0.001). Gingivitis patients had significantly higher GCF hCAP18/LL-37 levels than controls (p < 0.001). No significant differences were observed in serum hCAP18/LL-37 levels among the study groups (p = 0.524). While there were positive correlations between GCF hCAP18/LL-37 levels and periodontal parameters of sampling sites (p < 0.005), no significant correlation was observed between serum hCAP18/LL-37 levels and whole-mouth periodontal parameters (p > 0.05). Increased levels of GCF hCAP18/LL-37 in G-AgP might show that it is abundantly expressed in the presence of periodontal tissue destruction. Serum hCAP18/LL-37 levels do not seem to be related with the presence of G-AgP. hCAP18/LL-37 antimicrobial peptide might be associated with periodontal tissue destruction in the presence of aggressive periodontitis.