IMMUNOHISTOCHEMICAL STUDY OF 30 CASES OF CYCLOSPORINE-A-INDUCED GINGIVAL OVERGROWTH

IMMUNOHISTOCHEMICAL TECHNIQUES WERE USED TO STUDY the presence of cycl osporin A (CsA) and leukocyte subsets in 30 gingival biopsies of renal transplant subjects with gingival overgrowth (GO). Statistical analys is revealed significant differences in the total number of inflammator y cells determined by monoclonal antibody CD45, the monocyte/macrophag e (CD68) subset, the plasmatic cells (EMA), and the total of T-lymphoc ytes (CD3) (P < 0.001, Student t test) between the treated subjects an d the healthy control group. Differences were found in the helper/indu cer T lymphocytes CD4 (P < 0.001 Student t test) and cytotoxic/suppres sor T lymphocyte (CD8) (P < 0.01, Student t test) subsets between both groups. The CD4/CD8 ratio was greater in the transplant subjects than in the control group (1.82 +/- 0.16 versus 1.35 +/- 0.05 respectively ) (P < 0.05 Student t test). There was no significant difference in th e populations CD16+, CD57+, and CD20+. The CD45+ CD4+, and CD68+ cells increased in number along with the degree of GO. The number of epithe lial cells/mm2 which displayed a deposit of CsA increased in accordanc e with the degree of GO (P < 0.05, Kruskal-Wallis's test). Likewise, t he intraepithelial deposit of CsA in the GO region was found to be rel ated to the inflammatory infiltrate CD4+, CD8+, and CD68+ (r = 0.7432; r = 0.7346; r = 0.77005, respectively). Our findings suggest that the intraepithelial deposit of CsA and the inflammatory infiltrate play a predominantly pathogenic role and are both related to the degree of G O.