Bioassay of interleukin 1 (IL-1) in human gingival crevicular fluid during experimental gingivitis.

The cytokine IL-1 was demonstrated in crevicular fluid during a 14- and 21-day experimental gingivitis in healthy human volunteers. A sensitive and specific bioassay allowed detection of biologically active IL-1 at levels ranging from 0.18 ng/microliters at baseline to 1.70 ng/microliters in inflamed gingiva. Levels of IL-1 increased rapidly with plaque accumulation and in advance of the subsequent gingival inflammation, peaking within 7 days of the start of gingivitis. As changes in IL-1 were detected before clinically recognizable gingival changes, IL-1 may have potential as an early marker of gingival inflammatory changes.