Cytoskeletal attachment of surface proteins in normal and 4.2-deficient RBCs. FIMD of CD47 on normal RhD-negative (-), normal homozygous RhD-positive (+), 4.2-Hammersmith (H), and 4.2-Nippon (N) cells shows significant changes in CD47 cytoskeletal attachment for 4.2-deficient RBCs. In 4.2-deficient RBCs, RhAG and Rh both have a reduced cytoskeletal connectivity compared to normal. The reduction of 30% in cytoskeletal attachment seen in band 3 is consistent with previous results for 4.2-Nippon RBCs.¹³