MesoscaleModeling of Muscle-Driven Contractions in Collecting Lymphatic Vessels

We develop a computational model of a single collecting lymphatic vessel (lymphangion) including deformable, elastic walls and valves.The vessel wall simulates smooth muscle cell contractions to mimic active vessel contraction and relaxation through a lymphangion contraction cycle. Muscle contraction is controlled by transmural pressure. Contractions are inhibited when the internal pressure exceeds a physiological threshold, replicating theinability of lymphatic muscle to contract under high loading. The model parameters,including vessel and valve geometry, wall stiffness,and contraction strength are set based on experimental data from isolated lymphangion studies. Validation confirms that the simulated dynamics closely replicate experimental wall motion and valve behavior. We employ this model to advance our understanding of the intrinsic lymphatic pumping mechanism in physiologically relevant conditions. The results are useful for the development of therapeutic and bioengineered systems for enhancing lymphatic function.