HLA-DR3 antigens in erosive oral lichen planus, cutaneous lichen planus, and lichenoid reactions

Abstract

HLA antigens were examined in patients with erosive oral lichen planus (OLP_e), cutaneous lichen planus (CLP), or lichenoid reactions (LR) adjacent to amalgam fillings. The control group had amalgam restorations in contact with the oral mucosa but without any reactions. A strong association was found between HLA-DR3 and OLP_c, with an RR value of 21.0 (p < 0.05). The corresponding values for CLP and LR were 2.3 and 1.5, respectively (NS). The haplotype A1-B8-DR3 was more frequently found in OLP_c (p < 0.05) and CLP (p < 0.05) than in LR and controls (NS). The data indicate that OLP_e, CLP, and LR, which present with virtually the same histopathologic features, are different in their association with HLA-DR3. Moreover, the increased frequency of HLA-DR3 in OLP_e suggests an autoimmune component in the pathogenesis of this disorder. □ Amalgam; aulo-immunity; clinical study; histopathology; HLA-typing