Immunofluorescence analysis of surface expression and intracellular localization of recombinant β3 integrin in transfected CHO cells. (A) FACS analysis of CHO cells in suspension after indirect immunofluorescence surface labeling with the anti-β3 MoAb P37. (B) Intracellular labeling of human β3 integrin in transfected CHO cells. The cells were grown on coverslips precoated with fetal calf serum, fixed, permeabilized, and processed for indirect immunofluorescence using the anti-β3 MoAb P37 and the complex-specific anti-αvβ3 LM609. (1) Mock-transfected CHO cells. (2) CHO cells transfected with wild-type β3 integrin. (3) CHO cells transfected with mutant β3-met. (4) CHO cells transfected with mutant β3-pro. (5) CHO cells transfected with mutant β3Δ744.