He. Pernu et Mle. Knuuttila, Macrophages and lymphocyte subpopulations in nifedepine- and cyclosporin A-associated human gingival overgrowth, J PERIODONT, 72(2), 2001, pp. 160-166
Background: Nifedipine and cyclosporin A (CsA) induce gingival overgrowth.
Both drugs have immunomodulating effects. It has been suggested that altere
d immune response is associated with drug-induced gingival overgrowth. In t
his study, we evaluated whether there were differences in macrophages and l
ymphocyte subpopulations in human nifedipine- and CsA-associated gingival o
vergrowth as compared with those in normal gingiva.
Methods: Biopsy samples of overgrown gingiva were obtained from 9 nifedipin
e-treated cardiac outpatients, 13 CsA-treated renal transplant recipients i
ncluding 9 patients who were also receiving nifedipine, and 30 healthy cont
rol individuals undergoing dental treatment. Serial 5 mum thick cryostat se
ctions were stained with mAbs for CD20 (B-pan), CD68 (macrophages), CD4 (T-
helper/inducer), and CD8 (T-cytotoxic/suppressor) using an avidin-biotin-ho
rseradish peroxidase complex method. Numbers of mAb-labeled and all nucleat
ed cells were determined in 3 areas: the connective tissue beneath the sulc
ular epithelium, the middle connective tissue, and the connective tissue be
neath the oral epithelium. Distributions of each type of cell were expresse
d as percentages of mAb-labeled cells in relation to total number of nuclea
ted cells in a counting zone. Significances of differences between groups w
ere tested by means of the Kruskal-Wallis test, and between pairs of result
s by means of the Mann-Whitney U-test.
Results: The proportion of CD8-labeled cells was significantly higher in co
nnective tissue beneath the sulcular epithelium in the nifedipine group tha
n in the controls (P = 0.014). In both medicated groups, the proportions of
CD68-labeled cells were higher in all counting zones than in the controls,
but statistically significantly only in the nifedipine group in the connec
tive tissue beneath the oral epithelium (P = 0.008). No intergroup differen
ces were found with respect to CD4- and CD20-labeled cells. The CD4/CD8 rat
io was significantly lower in connective tissue beneath the sulcular epithe
lium in the nifedipine group than in the controls (P = 0.013).
Conclusion: The results support the idea that immune response may be altere
d in drug-induced gingival overgrowth.