REACTIVITY OF MONOCLONAL-ANTIBODY-17.13 AND MONOCLONAL-ANTIBODY-63.12WITH ORAL EPITHELIAL DYSPLASIA AND HYPERKERATOSIS

Monoclonal antibodies (MAbs) 17.13 and 63.12 exhibit characteristic re activity patterns in normal stratified squamous epithelium, as well as highly sensitive and specific altered reactivity patterns in squamous cell carcinoma. The purpose of this study was to critically evaluate the patterns of reactivity of MAbs 17.13 and 63.12 in 43 biopsies of c linical oral leukoplakia or erythroleukoplakia with microscopic diagno ses of hyperkeratosis or epithelial dysplasia. Altered carcinoma-like reactivity patterns were seen in 72% of hyperkeratoses and in all case s of epithelial dysplasia, but varied in the level of epithelial strat a exhibiting altered reactivity. Increased frequency of altered reacti vity within the epithelial strata was associated with the presence, bu t not the grade of, epithelial dysplasia, as well as with the presence , intensity, and pattern of submucosal inflammation. The results of th is study suggest that altered reactivity patterns of MAb 17.13 are ass ociated with epithelial dysplasia and may be of assistance in detectin g precancerous changes in hyperkeratoses before morphologically identi fiable epithelial dysplasia. The association of submucosal inflammatio n with altered MAbs 17.13 and 63.12 reactivity may indicate either a d ecrease in specificity of these antibodies for precancerous change or an increased significance of inflammation in precancerous lesions.