Flow Cytometry Assay for Recycling of LFA-1 in T-lymphocytes

To enable cells to move forward, cell surface integrins are internalized into an endosomal compartment and subsequently intracellularly transported to be re-exposed at a new site on the cell membrane. Leukocytes are the fastest migrating cell type in the human body, which express the leukocyte-specific integrin LFA-1. Here, we describe a flow cytometry-based assay that allows the quantification of LFA-1 internalization and its re-expression on the cell surface in T lymphocytes. An advantage of using flow cytometry-based assay over biochemical methods is the low number of needed cells. This protocol can be also used to measure recycling of other receptors.