The influence of cell surface properties on the arrest of circulating melanoma cells

B16 mouse melanoma sublines cultured in vitro spontaneously shed intact vesicles of plasma membrane. These vesicles can be fused with the plasma membrane of cells from homologous and heterologous B16 sublines using polyethylene glycol (PEG) and phytohemagglutinin (PHA). The ability of FI cells to arrest in the lung and form metastases in this organ is significantly increased by fusion of vesicles from a highly metastatic subline (F10) that localizes exclusively in the lung with cells from another subline (F1) which is poorly metastatic and produce few lung metastases. In contrast, fusion of F1 vesicles with F10 cells does not reduce their ability to localize in the lung of form lung metastases. Vesicle-treated F1 cells revert to their original arrest behavior and metastatic capacity following removal of F10 vesicle components from the plasma membrane. The changes in the arrest and metastatic behavior of F1 cells induced by F10 vesicles are highly specific. Vesicles from other B16 sublines which show limited abilities to localize in the lung (F1, F1(1r) and F10(1r) fail to modify the arrest behavior of F1 cells. These results suggest that the differences in the ability of the F1 and F10 sublines to localize in the lung are determined by differences in surface properties.