Affinity chromatography of 125I surface labeled proteins on III1-C Sepharose RASMCs were surface labeled with 125 I, lysed in octylglucoside lysis buffer, and these cell lysates were passed over affinity columns containing either FN (FN), III1-C (C), or III 11-C (11C). The columns were washed and bound proteins were eluted with 10 mM EDTA in lysis buffer. Samples from the final wash before elution (W lanes), and from the elution (E lanes) fractions of each column were analyzed by SDS-PAGE and phosphorimager analysis. Numbers to the left of the panel indicate the migration of molecular mass markers (kDa). Asterisks mark the positions of bands that bound to and were eluted from the FN and III1-C columns.