Detection of antibodies against p63 and p73 isoforms in sera from patients diagnosed with oral lichen planus

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory disease of oral mucosa. Despite numerous publications and intense research, the etiology of OLP is still unknown, however, autoimmunity as a possible causative factor has been discussed. METHODS: In the present study sera from 20 patients clinically and histologically diagnosed with OLP were analyzed for antibodies directed toward p53, p63, and p73 using Western blot. RESULTS: Sera from two patients reacted with all six p63 isoforms, and one also with p73. The strongest reaction was noted against the TAp63 beta protein, which is the most potent transactivator of all p63 proteins and is implicated in the differentiation of stratified epithelia. CONCLUSIONS: This is the first demonstration of antibodies directed against all p63 and some p73 isoforms in sera from patients diagnosed with OLP.