The lymphatic system transports fats in the form of lipoproteins and also generates immunity in response to vaccines. Lymphatic function has important roles in the progression of cardio-metabolic diseases including atherosclerosis which is a global leading cause of death. HDL was found to return cholesterol from tissue to plasma via transit through lymph, such that lymphatic function appears crucial for cholesterol removal from tissue deposits e.g. artery walls. This thesis presents novel findings on HDL biology, transport and modification in the lymphatics and its potential application as a carrier to improve the delivery and effectiveness of vaccines.