1. Confocal microscopy of normal human kidney Immunostained for cell surface protein EpCAM (red) and normal MUC1. Normal MUC1 is found at the cellular surface in human kidney.
2. Normal human kidney immunostained for EpCAM and Tn-MUC1 (green). Tn-MUC1 is found intracellular in normal MUC1-expressing tissues.
3. Human breast cancer immunostained for EpCAM and Tn-MUC1. Tn-MUC1 is found at the cell membrane in cancer.
Avery Posey, Ph.D., Perelman School of Medicine, University of Pennsylvania