Figure 9

Covalent dimerization of MUC1 following ICAM-1 binding. A. Breast cancer cell line T47D and 293T-MUC1-CFP cells were stimulated with NIH-ICAM-1 cells for 10 s or 60 s and treated with DSS, lysed, ran on SDS-PAGE and probed with anti-MUC1-CD. B. Breast cancer cell line MCF-7 and 293T MUC1-CFP cells were lysed with or without prior treatment with NIH ICAM-1 cells for 60 seconds. Lysates were subjected to reducing ("R"; β-mercaptoethanol added) or non-reducing ("NR"; no β-mercaptoethanol) conditions, ran on separate SDS-PAGE to prevent diffusion of β-mercaptoethanol and probed with anti-MUC1-CD. C. 293T CD8/MUC1 cell lysate was run under reducing or non-reducing conditions, ran on separate SDS-PAGE to prevent diffusion of β-mercaptoethanol and probed with anti-MUC1-CD. "D" and "M" indicate expected molecular weights of dimer and monomer, respectively. Whole cell lysates (WCL) are included as controls.