Immunoexpression of interleukins 6, 17 and 18 in oral lichen planus

Objective To analyze the immunohistochemical expression of IL-6, IL-17, and IL-18 in OLP. Study Design Forty paraffin-embedded specimens, diagnosed as OLP, were selected and clinicopathological characteristics were retrieved. Immunohistochemical reactions against IL-6, IL-17, and IL-18 were performed. Results Patients were mostly adults, with no gender predilection. Lesions affected mostly the buccal mucosa (85%), gingiva (47%), and tongue (42%), which is reticular in 14 patients (35%), and reticular and atrophic/erosive in 26 (65%). Hyperkeratosis was observed in 21 cases (53%), and exocytosis of T CD4+ and T CD8+ lymphocytes in, respectively, 17 (42%) and 30 (75%) cases. IL-6 was the most expressed IL both in epithelium and connective tissue. IL-17 expression was intense in the connective tissue from 40% of the cases. IL-18 expression was mild/moderate both in epithelium (40% of the cases) and connective tissue (45% of the cases). Exocytosis was associated with higher ILs expression, and expression of IL-17 was higher in hyperkeratotic epithelium. Conclusion Expression of the studied ILs was associated with exocytosis of T CD4+ and T CD8+ lymphocytes, and can be associated with the epithelial alterations found in OLP. Funding CNPQ and FAPERJ To analyze the immunohistochemical expression of IL-6, IL-17, and IL-18 in OLP. Forty paraffin-embedded specimens, diagnosed as OLP, were selected and clinicopathological characteristics were retrieved. Immunohistochemical reactions against IL-6, IL-17, and IL-18 were performed. Patients were mostly adults, with no gender predilection. Lesions affected mostly the buccal mucosa (85%), gingiva (47%), and tongue (42%), which is reticular in 14 patients (35%), and reticular and atrophic/erosive in 26 (65%). Hyperkeratosis was observed in 21 cases (53%), and exocytosis of T CD4+ and T CD8+ lymphocytes in, respectively, 17 (42%) and 30 (75%) cases. IL-6 was the most expressed IL both in epithelium and connective tissue. IL-17 expression was intense in the connective tissue from 40% of the cases. IL-18 expression was mild/moderate both in epithelium (40% of the cases) and connective tissue (45% of the cases). Exocytosis was associated with higher ILs expression, and expression of IL-17 was higher in hyperkeratotic epithelium. Expression of the studied ILs was associated with exocytosis of T CD4+ and T CD8+ lymphocytes, and can be associated with the epithelial alterations found in OLP.