Abstract
Transcytosis is the primary mechanism by which macro-molecules transverse epithelial cell barriers. Here, we present an assay for measuring transcytosis and recycling of IgG in intestinal epithelial Caco-2 cells and primary human intestinal organoids. We describe steps for establishing human enteroids or Caco-2 cells and plating monolayers. We then provide procedures for a transcytosis and recycling assay and a luciferase assay. The protocol facilitates quantification of membrane trafficking and can be used to probe endosomal compartments unique to polarized epithelia. For complete details on the use and execution of this protocol, please refer to Maeda K et al. (2022).1.