Benign and neoplastic eosinophilic staining cells: an immunofluorescence study.

Deposition of immunoglobulins, complement and fibrinogen on eosinophilic staining cells was investigated using direct immunofluorescence techniques. Serum factor deposition was detected on benign epidermal eosinophilic cells seen in pityriasis lichenoides et varioliformis acuta, sunburn erythema and, in addition, on subepidermal hyaline bodies in lichen planus; no such deposition occurred on neoplastic eosinophilic cells in Bowen's disease and squamous cell carcinoma. The qualitative findings of immunofluorescence microscopy seem to be different in inflammatory and malignant dermatoses.