Sequential enumeration of peripheral blood T cell subsets in lichen planus

Peripheral T-cell subsets in patients with reticular and atrophic-erosive oral lichen planus

OBJECTIVE

Oral lichen planus (OLP) presents with various clinical forms that can be classified into 2 major types: reticular OLP and atrophic-erosive OLP. Our objective was to investigate immunologic differences between these 2 types.

STUDY DESIGN

We investigated possible immunologic differences between 26 patients with reticular OLP and 26 patients with atrophic-erosive OLP.

RESULTS

No differences were detected in serum Ig levels or complement levels. However, the mean proportions of CD4+CD45RO+ and DR+ lymphocytes were significantly higher in patients with atrophic-erosive OLP than in patients with reticular OLP, whereas the mean proportion of CD8+CD45RA+ lymphocytes was significantly lower in patients with atrophic-erosive OLP.

CONCLUSION

These findings suggest that the 2 clinical types of OLP might have different immunopathogenic mechanisms.

Oral lichen planus. A review

Lichen planus is a mucocutaneous disease of unknown etiology which, according to current knowledge, may represent a cell-mediated immunological response to induced antigenic changes in the skin and mucosa. Oral lichen planus (OLP) is a disease of adulthood and as one of the most prevalent diseases affecting the oral mucosa it has been the subject of intensive research during recent years. Ultrastructural and immunohistochemical studies particularly dealing with the subepithelial inflammatory cell infiltrate and its relations to epithelial pathology, the basal cell region and the intraepithelial antigen presenting Langerhans' cells, have contributed vastly to our knowledge of the pathogenesis of OLP. However, the treatment of OLP still remains largely symptomatic because many as yet unknown factors, active in the disease process, still remain to be elucidated.

Subsets of T lymphocytes in peripheral blood of patients with oral lichen planus

The T lymphocyte subsets in the peripheral blood were studied in 26 patients with oral lichen planus and in 11 normal controls. Lymphocyte subsets were identified with monoclonal antibodies (Ortho Diagnostic System Inc. Raritan, New Jersey, USA) by an indirect immunofluorescent antibody method. This study shows no significant difference between patients with oral lichen planus and healthy controls. The conclusion is that local immunity, due to the breakdown of skin-associated lymphoid tissue, not a generalized immunologic disorder, is considered to be involved in the pathogenesis of oral lichen planus.

Activation marker analysis of mononuclear cell infiltrates of oral lichen planus in situ

Monoclonal activation markers (Ia, Tac, T9, and 4F2) were used to detect the degree of activation of mononuclear cells in the inflammatory infiltrates of oral lichen planus in situ. In addition the specimens were stained with the following monoclonal antibodies: T4, T8, T11, M1, and pan-B. T-lymphocyte was the predominant cell type in the inflammatory infiltrates. According to the results of the activation marker analysis, the majority of the T-lymphocytes were resting. However, activated cytotoxic T8 and 4F2 T-cells were located close to damaged basal cells; this finding may suggest that they are responsible for the damage and supports the claim that a cell-mediated immune response participates actively in local pathogenetic mechanisms in oral lichen planus.