Specificity
This anitbody detects a melanoma-associated proteoglycan (MW greater than 450-250 kDa) and a molecular complex, which under reducing conditions consists of 4 compounds of 120, 95, 29 and 25 kDa respectively. It reacts with cultured melanomas melanomas in frozen sections, and blocks fibronectin-induced chemotaxic motility and chemokinesis of melanoma cells. The antigen is strongly associated with the adhesion and cytoplasmic spreading of melanoma cells to plastic surfaces and monolayers of vascular endothelial cells. In addition to their membrane localization, the antigens are abundant in extracellular adhesion plaques deposited by cultured melanoma cells. NKI-M7 stains primary tumors heterogeneously, whereas metastases are homogeneously stained.