Effects of anti-Integrin α5 chain (CD49e) antibodies on K562 cell binding to fibronectin. Aliquots of K562 cell suspension, an erythroleukemia cell line expressing Integrin α5 chain (CD49e) receptor, were incubated in the presence of the designated concentrations of Purified NA/LE Mouse Anti-Human Integrin α5 chain (CD49e) (Cat. No. 555614, • ) or Purified Mouse Anti-Human CD49e (Cat. No. 555651, □), for 30 minutes at room temperature. The suspensions were then transferred to plastic microtiter wells precoated with 12 µg/mL of fibronectin and incubated for 45 minutes at 37°C. Unattached cells were removed by aspiration and washing with PBS, and the attached cells were semi-quantitated using toluidine blue staining. The resulting absorbance signals are expressed relative to the average signal obtained without antibody.