Relative proportions of mononuclear cell types in periodontal lesions analyzed by immunohistochemistry

In this study, we investigated the relative proportions of infiltrating mon onuclear inflammatory cells in sections of granulation tissue from periodon titis lesions in both adult periodontitis (AP) and early onset periodontiti s (EOP) patients. We utilised a set of cluster of differentiation (CD antig en-specific monoclonal antibodies to detect different cell types within the tissues, These included anti-CD 20 (B cells), anti-CD 3 (pan T cells) and anti-CD 45RO (memory T cells), anti-CD 4 (helper T cells) anti-CD 8 (suppre ssor T cells) and anti-CD 68 (monocyte/macrophage). Biopsies of granulation tissue were obtained from 9 patients with adult periodontitis (AP), from 1 0 patients with early onset periodontitis (EOP) and for comparative purpose s, biopsies of gingival tissue from 4 patients with AP. A significantly gre ater number of T cells (p<0.05) were observed in EOP and gingival sections than in AP sections. In addition, a greater number of B cells were observed in the granulation tissues than in the gingiva (p<0.05). The relative numb ers of B cells (CD 20). T cells (CD 3) and macrophages (CD 68) were express ed as a percentage of their combined total for each of the patient groups a nd indicated that the proportion of B lymphocytes was greater in AP section s than in EOP or gingival sections (p<0.02). The proportion of T cells was lower in the AP periodontitis sections than in the EOP periodontitis sectio ns (p<0.05). There were no significant differences in the proportion of mac rophages between the 3 categories of tissue specimens. The relative ratios of B cells (CD 20) to T cells (CD 3) and B cells (CD 20) to memory T cells (CD 45RO) and macrophages (CD 68) to T cells (CD 3) and memory T cells (CD 45RO) were analyzed and indicated that there was a significant increase in the B to T cell ratio in AP sections compared to EOP and gingival sections (p<0.02). There was also a significant increase in the macrophage to T cell ratio in AP sections as indicated by CD 68 to CD 3 ratios (p<0.05). There were no differences regarding the relative proportions of memory T cells or in the ratios of CD 4+ to CD 8+ T cells in the different disease categorie s. In conclusion, these differences in the relative proportions of B cells, T cells and macrophages may reflect a difference in the immunopathology of AP and EOP.