Immunohistochemical Analysis of Antimelanoma Monoclonal Antibodies, with Special Reference to Fetal Tissue Distribution

An immunohistochemical study using 2 antihuman melanoma monoclonal antibodies designated as MoAb 225.28S and MoAb 653.40S was carried out on various human skin tumors, including malignant melanoma as well as on normal and fetal tissues by indirect immunofluorescence technique. Specific immunofluorescence was observed not only in malignant melanoma cells but also in cells of pigmented nevi, basal cell epithelioma, normal hair follicles, and some fetal tissues. Both monoclonal antibodies were revealed to be able to recognize the common antigenic determinant shared by several skin tumors, including malignant melanoma, and fetal tissues. Therefore, both monoclonal antibodies might recognize premature antigen of both melanocytic and keratinocytic cell lineage.