The antimicrobial peptide LL-37 is anti-inflammatory and proapoptotic in human periodontal ligament cells.

Research output: Contribution to journalArticle


The antimicrobial peptide LL-37 is anti-inflammatory and proapoptotic in human periodontal ligament cells. J Periodont Res 2011; doi: 10.1111/j.1600-0765.2011.01436.x. © 2011 John Wiley & Sons A/S Background and Objective: The antimicrobial peptide LL-37 is expressed in periodontal tissue, and variations in LL-37 levels have been associated with periodontal disease. The effects of LL-37 on periodontal ligament cell function have not been described before. Here, we assess anti-inflammatory properties of LL-37 and investigate the effects of LL-37 on cell differentiation, cell proliferation and apoptosis in human periodontal ligament cells. Material and Methods: Periodontal ligament cells were obtained from teeth extracted for orthodontic reasons. Cytokine (interleukin-6) and chemokine (monocyte chemoattractant protein-1) expression was determined by quantitative PCR, cell differentiation by alkaline phosphatase activity, cell proliferation by counting cells in a Bürker chamber, DNA synthesis by incorporation of radiolabeled thymidine and apoptosis by cell morphology and activated caspase 3 quantities. Results: Treatment with 0.1 and 1 μm of LL-37 totally reversed lipopolysaccharide-induced monocyte chemoattractant protein-1 expression and suppressed lipopolysaccharide-induced interleukin-6 expression by 50-70%. LL-37 had no effect on alkaline phosphatase activity. Incubation with 8 μm LL-37 strongly reduced cell number. DNA synthesis was attenuated by about 90% in response to 8 μm LL-37, confirming its antiproliferative effect. Cell morphology was altered in an apoptosis-like fashion in cells treated with 8 μm LL-37. Furthermore, the quantity of activated caspase 3 was increased in cells treated with 1 and 8 μm of LL-37, suggesting apoptosis. Conclusion: LL-37 strongly attenuates lipopolysaccharide-induced cytokine and chemokine expression and, in high concentrations, reduces cell proliferation through inhibition of DNA synthesis and by promoting apoptosis in human periodontal ligament cells.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Dentistry
Original languageEnglish
Pages (from-to)330-335
JournalJournal of Periodontal Research
Publication statusPublished - 2012
Publication categoryResearch