Specificity of human keratinocyte X HeLa cell hybrid murine monoclonal antibodies

The immunofluorescent staining patterns of three differentiation-specific monoclonals (HLK3, HLK7, HLK20) that display different immunofluorescent (IF) reactivity in normal and psoriatic epidermis, were examined in basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), as well as other human normal epithelial and nonepithelial tissues. Similar staining patterns within epidermis were seen with HLK3 (intercellular) and HLK7 (perinuclear) in psoriasis, SCC, and BCC. HLK20 selectively stained BCC and SCC within epidermis and dermis, and was negative in psoriasis. The monoclonals did not react with nonepithelial tissues, but repetitively displayed positive, granular reactivity with simple epithelia and transitional epithelium. Stratified squamous epithelia showed IF staining similar to normal epidermis for all three monoclonals. These new monoclonal antibodies offer new investigative tools to study abnormalities in keratinocyte differentiation in benign and malignant hyperplastic skin diseases.