Expression of recombinant β3 integrins in CHO cells.

(A) Western blot analysis of recombinant β3 integrin expression in CHO cells. Cell lysates of transfected CHO cells were prepared, and protein concentration was determined as described in “Materials and methods.” Equal amounts of protein from β3-transfected CHO cells (50 μg) were resolved by 8% SDS-PAGE under nonreducing conditions, transferred onto nitrocellulose, and immunoblotted with a mAb to human β3 (P37). Platelet lysate (5 μg protein) was run in parallel as a positive control. Clone A10, CHO-αIIbβ3Leu33Arg93; clone CAM12, CHO-αIIbβ3Leu33Gln93; clone A13, CHO-αv_hamsterβ3Leu33Arg93; clone CAM11, CHO-αv_hamsterβ3Leu33Gln93; clone E05, CHO-αv_hamsterβ3Pro33Arg93. (B) FACS analysis of CHO cells in suspension after indirect immunofluorescence labeling with the anti-β3 integrin mAb P37. Negative control cells (bold solid line), CAM11 (solid line), CAM12, A13, E05 (dotted lines), A10 (dashed line).