Fork head box P3 (FoxP3+) regulatory T cells (Tregs) are specialized T cells for the prevention of hyperimmune responses and autoimmunity. Tumors and pathogens can hijack FoxP3+ Tregs to evade host immune responses. There is an increasing body of evidence that trafficking of FoxP3+ Tregs is important for their effective suppression of target cells. Because of their distinctive functions and gene expression phenotype, the migratory behavior of FoxP3+ Tregs has been somewhat mystified. The myths are that they have unique trafficking receptors and migratory behaviors that are different from those of conventional T cells. Another related myth is that FoxP3+ regulatory T cell subsets have a fixed trafficking behavior from the time they are generated in the thymus. Recent progress in trafficking receptors and the migratory behavior of FoxP3+ Tregs are reviewed here and the validity of these myths examined.
Chang H. Kim, Laboratory of Immunology and Hematopoiesis, Department of Comparative Pathobiology, Purdue University, 725 Harrison Street, West Lafayette, IN 47907, USA