Expression of FcR on PMN from adult periodontitis patients. (A) Representative flow cytometric histograms showing the expression of FcR (FcαRI [CD89], FcγRI [CD64], FcγRIIa [CD32], and FcγRIIIb [CD16]) on PMN from PB and GCF (solid lines) in a patient with adult periodontitis. The isotype-matched control profiles are shown by broken lines. AU, arbitrary units. (B) Expression of FcR on PB PMN and GCF PMN from 21 patients with adult periodontitis. Results are presented as mean fluorescence intensities on an arbitrary scale. Horizontal bars indicate the means for each group. (C) Percentages of FcR-positive PMN from PB and GCF in 21 patients with adult periodontitis. Results are presented as percentages of PMN showing specific fluorescence after labeling with anti-CD89, -CD64, -CD32, or -CD16 MAb. Horizontal bars indicate the means for each group. The P values reflect differences between the PB and GCF PMN groups, identified by paired t tests.