Polymeric IgA binds to the polymeric immunoglobulin receptor on the basolateral surface of epithelial cells and is taken up into the cell via transcytosis.
Polymeric IgA binds to its receptor on the surface of epithelial cells and is then engulfed by the cell via a transport mechanism. This process involves the interaction between polymeric IgA and its receptor on the basolateral side of epithelial cells.