Methods: 97 patients aged 18 to 60 years were studied including 35 with erosive oral lichen planus, 32 with non-erosive oral lichen planus and 30 healthy control subjects of similar age. The levels of serum cytokines (TNF-α, IL-12, IL-8) were determined by enzyme-linked immunosorbent assay ("Immunotech"; France).
Results: During relapse of erosive oral lichen planus there is a marked increase compared with control group in: IL-12, 2.0 fold rise (15.3±1.1 pg/ml versus 8.6±0.6 pg/ml); IL-8, 2.8 fold rise (83.1±2.3 pg/ml versus 30.1±1.2 pg/ml); and TNF- α, 1.2 fold reduction (18.4±9.2 pg/ml versus 21.4±6.1 pg/ml). In remission IL-12 increases 1.2 fold, IL-8 increases 2.3 fold, and TNF-α increases 2.4 fold, being less than in healthy controls, (p<0.05).
Conclusions: Acute relapse and chronic stages of lichen planus of the oral mucosa are both characterized by immune changes detectable in peripheral blood serum including increases in IL-12, IL-8, and TNF-α, characteristic of recurrent inflammatory immune responses.