Method: Samples of reticular OLP (15), erosive OLP (15) and inflammatory fibrous hyperplasia (15-control) were employed. Immunohistochemical analyses were performed to evaluate the expression of caspase-8, caspase-3, Bax, and Bcl2, as well as the presence of CD8+ T lymphocytes.
Result: No immunostaining was detected for caspases-8 and 3 in the inflammatory infiltrates of erosive and reticular OLP. In contrast, both caspases had an intense immunoexpression in the control group. Bax was not detected in any of the groups studied. The index of CD8+ and Bcl2+ cells was higher in the OLP samples than in the control group. Furthermore, the number of Bcl2+ cells was significantly higher in the erosive than in the reticular type of OLP.
Conclusion: The data suggest that the intrinsic apoptotic pathway is being blocked by Bcl2 expression in the inflammatory infiltrates of OLP, especially in the erosive type contributing for the persistence of inflammation and evasion of apoptosis in that lesion.