Immunoblotting of chymotrypsin-treated K562 cells for band 3, 8% Laemmli gel. Lanes 1 and 4, ghosts of chymotrypsin-treated homozygous Memphis RBCs; lanes 2 and 3, chymotrypsin-treated K562/B3 clone 1 cells; lane 5, PNGase-treated ghosts of chymotrypsin-treated homozygous Memphis RBCs.