title: Immunoperoxidase staining for Ia-like antigens in paraffin-embedded tissues from human melanoma and lung carcinoma.
abstract: The human Ia-like antigens that are predominantly expressed by cells associated with immunologic function has been considered as a diagnostic marker of malignant transformation of some nonlymphoid tissues. Immunoperoxidase staining of formalin-fixed and paraffin-embedded tissue sections with a monoclonal antibody to Ia-like antigens was chosen for assessment of the value of this marker for diagnosis in surgical pathology. Monoclonal antibody LK8D3 developed against a human melanoma cell line bearing Ia-like antigens was found to react in serologic and immunochemical studies with an antigenic determinant of Ia-like antigens that was relatively stable to formalin fixation and paraffin embedding. Avidin-biotin complex peroxidase staining of formalin-paraffin sections with LK8D3 showed focal expression of Ia-like antigens in 3 of 12 melanomas, whereas all 8 cases of intradermal nevi were negative. Immunoperoxidase staining of formalin-paraffin sections of lung carcinomas with antibody LK8D3 was related to the histologic subtype of tumors. Thus, squamous cell carcinomas showed only very focal staining for Ia-like antigens in 5/9 cases, while widespread and intense Ia-like immunoreactivity was seen in 3/5 cases of lung adenocarcinomas, including two bronchioalveolar carcinomas. The presence of Ia-like antigens in lung adenocarcinoma may not be entirely associated with malignant transformation, because normal alveolar lining cells were stained with the antibody.
mesh_terms: D000230:Adenocarcinoma / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D000951:Antigens, Neoplasm / Q000032:analysis*; D002294:Carcinoma, Squamous Cell / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel; D000949:Histocompatibility Antigens Class II / Q000032:analysis*; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000276:immunology*; D008545:Melanoma / Q000276:immunology*; D009506:Nevus / Q000276:immunology; D011233:Precipitin Tests
chemical_list: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D000949:Histocompatibility Antigens Class II