Serum Levels of IL-22 in Patients with Oral Lichen Planus and Cutaneous Lichen Planus

STATEMENT OF THE PROBLEM: Lichen planus disease is a chronic inflammatory disorder of mucosal and cutaneous tissues with yet unclear etiology and pathogenesis. Cytokines play an important role in the initiation, maintenance of inflammatory and intercellular crosstalk. PURPOSE: We assessed serum levels of IL-22 in patients with oral and cutaneous lichen planus and made comparison with healthy individuals. MATERIALS AND METHOD: In this case-control study, peripheral blood samples of 40 patients with lichen planus disease, included two groups of oral lichen planus (n=20) and cutaneous lichen planus (n=20) were compared with 32 healthy individuals in this case-control study. Serum samples were prepared from patients with lichen planus and IL-22 concentration was measured in each serum sample by using a commercial ELISA Kit. The obtained data were then analyzed using the Kruskal-Wallis (one-way ANOVA) test. RESULTS: The IL-22 serum levels were significantly higher in patients with oral lichen planus compared to the healthy control group (p< 0.001). No statistically significant differences were observed in serum levels of IL-22 in cutaneous lichen planus patients compared to the controls (p= 0.183). CONCLUSION: Increased IL-22 serum levels in patients with oral lichen planus may play an important role in the pathogenesis of oral lichen planus. The administration of the recombinant or antagonist of IL-22 could be a new therapeutic opportunity in the treatment of oral lichen planus.