Researchers discovered why neonatal mouse hearts can regenerate while adult hearts cannot. In newborns, cardiac lymphatic vessels have immature, impermeable junctions that prevent beneficial macrophages from being drained away. This allows pro-regenerative immune cells to remain in the heart tissue and facilitate healing. The study found that LYVE-1, a protein on both lymphatic vessels and macrophages, plays a crucial role in keeping these healing cells in place during the critical regenerative window.
