This work determined the levels of expression of CD11c by neutrophils (PMNs) collected from subjects with various periodontal conditions. The percentages of CD11c-positive crevicular fluid PMNs were significantly lower than those of peripheral blood PMNs, but the levels of CD11c expression were similar in PB-PMNs and CF-PMNs (P<0.001). On the other hand, no significant difference could be found between the groups, either for the percentages of CD11c-positive cells or for the CD11c expression levels.