Native western blot analysis of human MDA-MB-231 breast cancer cell lysate (lanes 1 & 2),human recombinant CD55 extracellular region protein (lane 3), and CD44 extracellular region protein (lane 4). The blots were probed with mouse monoclonal anti-CD55 (CM0331) at 1:1000 (lane 1) and 1:4000 (lanes 2, 3, and 4).