ObjectiveThis study aimed to compare the differences of B cells, plasma cells, and related cytokines expression in gingival tissues between periodontitis and periodontal healthy subjects.MethodsGingival tissues were collected from periodontal healthy subjects (periodontal healthy group,n=12) and periodontitis patients (periodontitis group,n=15). Hematoxylin-eosin (HE) staining was used for histopathological examination. Immunohistochemical staining (CD19, CD38, and CD138) was applied to detect the expression of B cells and plasma cells. B cell-activating factor (BAFF) and soluble receptor activator of nuclear factor-κB ligand (sRANKL) were detected by enzyme-linked immunosorbent assay.ResultsExtensive inflammatory cell infiltration was found in the gingival tissues of the periodontitis group. The number of CD19(+), CD38(+), and CD138(+) cells of the periodontitis group was significantly higher than that of the periodontal healthy group (P<0 .000 1). baff and srankl levels of the periodontitis group were higher than those of the periodontal healthy group (P<0 .01,P<0 .001, respectively).ConclusionThe expression of B cells, plasma cells, and their related BAFF and sRANKL cytokines were significantly higher in periodontitis patients than those in the periodontal healthy subjects, suggesting that B cells and plasma cells may be involved in the development of periodontitis.