Exogenous expression of wild-type and functional mutants of the CX
CR1 receptor in MDA-436 breast cancer cells. Western blotting analysis of total cell lysates collected from parental MDA-436 cells as well as cells stably overexpressing the wild-type CX3CR1, the adhesion-impaired Y14F mutant or the chemotaxis-impaired R128N mutant of the receptor. Actin was used as a loading control (A); the correct insertion of each exogenously overexpressed form of the CX3CR1 receptor at the plasma membrane level of transfected MDA-436 cells was confirmed by cell-surface protein isolation (B). Cell lysates from the THP-1 human monocytic cell line were included as a positive control for CX3CR1 expression. Actin detected in the cytosolic fraction was used as a loading control.