Bacteriolytic activity of human gingival exudate

We investigated the bacteriolytic activity of gingival crevicular fluid (CF) on¹⁴C-labeled Streptococcus faecalis, Streptococcus mutans, Staphylococcus aureus, and on whole dental plaque. CF was collected from 100 healthy donors pooled and centrifuged at 200 g. CF supernate and a frozen and thawed extract of the pellet were interacted with the different bacterial strains, while Streptococcus faecalis and Staphylococcus aureus released 60% and 75% of the radioactive label, only 38% of it was solubilized from Streptococcus mutans, following their incubation with the CF supernate. The findings agreed with results obtained by interacting bacteria with a frozen and thawed lysate of human peripheral blood leukocytes. On the other hand, extracts from frozen and thawed CF pellet were inactive. Further, lipoteichoic acid and lipopolysaccharide were released by CF from Gram-positive and Gram-negative bacteria, respectively. The role of bateriolytic factors, present in CF, as a result of the interaction between microorganisms and leukocytes at inflammatory sites is discussed.