Vascular Biology Lymphatic vessels return fluid and immune cells from peripheral tissues back to the circulation. The growth of new lymphatic vessels and their remodeling are critical for clearing infection and, less helpfully, for metastasis of many cancer subtypes. Williams et al. identified genes that regulated lymphatic endothelial cell migration, a process that is essential for lymphatic vessel growth and remodeling. One of the top candidates, the glycan-binding protein galectin-1, promoted lymphatic vessel growth and was important for maintaining lymphatic endothelial cell identity. Sci. Signal. 10 , eaal2987 (2017).