Effects of LFchimera on Multispecies Oral Biofilm Formation In Vitro

Objectives: The purpose of this study was to determine the inhibitory effects of lactoferrin chimera (LFchimera), a heterodimeric peptide containing lactoferrampin (LFampin265–284) and a part of lactoferricin (LFcin17–30), on subgingival biofilm formation compared to chlorhexidine digluconate (CHX) and minocycline hydrochloride (MH) using an in vitro model.
Methods: Subgingival plaque samples from 5 periodontitis patients were cultivated in saliva-coated 96-well microtiter plates under anaerobic atmosphere at 37 °C for 24 h. Then LFchimera, CHX or MH were added and allowed to contact with adherent microorganisms for 15 min. Sonication was performed to dislodge adherent microorganisms. The bacterial suspension was transferred to the new 96-well microtiter plates and cultivated under anaerobic atmosphere at 37 °C for 24 h. Biofilm formation was determined quantitatively by crystal violet staining. The ratio of live/dead bacteria in biofilm was tested by fluorescence method using LIVE/DEAD BacLight Bacterial Viability kit.
Results: The results revealed that the inhibitory effect of LFchimera and CHX on biofilm formation appeared to be dose-related. A significant reduction (P < 0.05) of biofilm formation occurred after 15 min exposure to 20 µM of LFchimera and CHX compared to control. In contrast, MH at concentration up to 100 µM did not show that inhibitory effect. The ratio of live/dead bacteria in biofilm was also significantly lower after 15 min exposure to 20 µM of LFchimera compared to control and 20-50 µM of CHX and MH.
Conclusions: Altogether, the results obtained indicate that LFchimera is able to inhibit in vitro subgingival biofilm formation and reduce viability of multispecies bacteria in biofilm better than CHX and MH.