In-situ T lymphocyte identification in cutaneous tissue sections of benign and malignant dermatoses

An indirect immunoperoxidase technique employing a specific anti-human T lymphocyte antiserum has been used to identify T lymphocytes in cutaneous tissue sections of various benign and malignant dermatoses. Skin biopsies from patients with histologically confirmed lichen planus, discoid lupus erythematosus, psoriasis, actinic keratosis, squamous cell carcinoma, Bowen's disease, keratoacanthoma, malignant melanoma, inflamed serborrhoeic warts, sarcoidosis, follicular lymphoma and multicentric reticulohistiocytosis were examined. T lymphocytes were found to be the predominant cell type in the cutaneous infiltrates of the majority of these dermatoses. However, only few T lymphocytes were identified in sarcoidosis where they tended to be restricted to the periphery of the epithelioid cell granulomas. Similarly, in the cutaneous infiltrates of follicular lymphoma and in a patient with multicentric reticulohistiocytosis, few T lymphocytes were identified.