Specialized transendothelial dendritic cells mediate thymic T-cell selection against blood-borne macromolecules

Abstract

T cells are selected in the thymus, through interaction with self-antigens, to remove autoreactive cells. Here the authors show that a specialized thymic dendritic cell subset juxtaposes to microvessels, requires CX3CR1/CX3CL1 for this positioning, and has processes extruding into the blood stream to sample soluble macromolecules and assist in T cell selection.