Oral lichen planus: characterization of immunocompetent cells with hybridoma antibodies

Abstract

Monoclonal antibodies which react against T‐cell subpopulations and Langerhans' cells were used to examine the phenotype of immunocompetent cells in oral lichen planus. Immunomorphologically, the stromal infiltrate of this condition considerably resembled the delayed type of immune reaction. Although all subpopulations of immunocompetent cells were present in the stromal infiltrate, Langerhans' cells (OKT‐6 positive, HLA‐DR positive) and suppressor/cytotoxic T‐lymphocytes (OKT‐3 positive, OKT‐4 negative, OKT‐8 positive, HLA‐DR positive) predominated. Our immunohistological findings support the suggestion that aggregations of T‐lymphocytes are responsible for the cytotoxic processes which occur within the squamous epithelium in oral lichen planus.