Development and Function of Ovarian Lymphatic Vasculature

Lymphatic vessels play essential roles in interstitial fluid clearance and immune cell trafficking. Recent studies have uncovered previously unrecognized, organ-specific functions of the lymphatic vasculature in the meninges, heart, kidney, and lungs. However, the development and physiological significance of the ovarian lymphatic network remain poorly defined. To address this gap, we performed high-resolution three-dimensional imaging of ovarian lymphatic vasculature in mice. Our results reveal that the ovarian lymphatic network comprises lymphatic capillaries and valve-containing pre-collectors and the ovarian lymphatic vasculature arises from pre-existing lymphatic vessels in the broad ligament starting at postnatal day 5. Furthermore, we demonstrate that the VEGF-C/VEGFR-3 signaling is essential for ovarian lymphatic development and Vegfr 3 insufficiency impairs ovarian lymphangiogenesis, leading to fibrosis and premature ovarian aging. Together, these findings identify the lymphatic vasculature as a critical component of the ovarian microenvironment and establish a causal link between lymphatic insufficiency and accelerated ovarian aging.