Fig. 5. The role of CD82 in compartmentalisation of membrane proteins. Cells were lysed in ice-cold 1% Brij98/MES and the lysates were fractionated in 0.2-0.9 M gradient of sucrose as described in the Materials and Methods. Equal volumes of each fraction were resolved in 10% SDS-PAGE. Distribution of proteins in the gradient fractions was assessed by western blotting using specific antibodies: mAb-15 for EGFR, mAb-1 for ErbB2, mixture of mAbs C33 and TS82b for CD82; mAb 8G6 for EMMPRIN. Caveolin was detected using rabbit polyclonal antibody. The results of a representative (of three) experiment are shown.