LEVELS OF SPECIFIC IMMUNOGLOBULIN-G TO PORPHYROMONAS-GINGIVALIS IN GINGIVAL CREVICULAR FLUID ARE RELATED TO SITE DISEASE STATUS

Titers of immunoglobulin G (IgG) directed against Porphyromonas gingiv alis in gingival crevicular fluid of 40 periodontitis patients were me asured at three sites in each patient (healthy, gingivitis and periodo ntitis) by enzyme-linked immunosorbent assay. When paired analyses wer e; performed using Wilcoxon signed-rank tests, periodontitis sites wer e found to have lower median titers than gingivitis sites. Both system ic and locally-produced antibodies contribute to the overall gingival crevicular fluid antibody profile. Albumin, in contrast, is derived on ly from serum, and thus this protein serves as an indicator of serum c ontribution to gingival crevicular fluid. Correction was therefore mad e for systemic input to the gingival crevicular fluid IgG profile by e xpressing the results per unit of albumin. When this was done, periodo ntitis sites were also found to have significantly lower antibody leve ls than gingivitis sites. These findings suggest that a failure of loc al antibody production or reduction in quantities, by, for example, de gradation by bacterial proteases, may contribute to the change from a gingivitis to a periodontitis lesion.