Immuno-blot analysis of CHO cells transfected with human β3 integrin. Triton X-100 lysates of transfected CHO cells (100 μg protein) or SDS-solubilized platelet lysates (5 μg protein) were run in a 7% polyacrylamide gel and electrophoresed under nonreducing conditions, transferred to nitrocellulose, and incubated with the antihuman β3 MoAb 4D10G3. Lane 1, CHO cells transfected with wild-type β3; lane 2, mock-transfected CHO cells; lane 3, CHO cells transfected with the mutant β3-met cDNA construct; lane 4, CHO cells transfected with the mutant β3-pro construct; lane 5, α-chymotrypsin–digested platelet lysate; lane 6, control undigested platelet lysate.