Abstract:
Proper lymphatic function is essential to a variety of important physiologic processes including immune cell trafficking, lipid absorption, and the regulation of fluid balance. However, the experimental difficulties associated with making actual measurements on lymphatics have slowed our understanding of these processes. In vitro experiments on isolated primary lymphatic endothelial cells or lymphatic muscle cells remove the cell from its native biological and mechanical microenvironment, making the interpretation of results challenging. In vivo experiments, on the other hand, often require highly invasive and terminal procedures to access the vessels. In this talk I will describe the application of several in vitro and in vivo experimental platforms we have developed to shed light on the specific manor in which lymphatics fulfill their roles in immunology, fluid balance, and lipid transport. Through the development of near infrared (NIR) imaging approaches we can non-invasively measure the deterioration of lymphatic transport in both small and large animal models of lymphatic dysfunction. Using this same technology, in collaboration with the Vannberg lab in Biology at Georgia Tech, we have demonstrated that lymphatics rapidly transport exosomes from the periphery to lymph nodes, where they are selectively taken up by macrophages at the lymph node sinus. These examples serve to remind us that this “invisible” circulatory system has acquired essential functions that have broad implications in a variety of physiologic and biological processes.

Speaker Bio:

Dr. Dixon began at Georgia Tech in August 2009 as an Assistant Professor. Prior to his current appointment, he was a staff scientist at Ecole Polytechnique Federal de Lausanne (Swiss Federal Institute of Technology - Lausanne) doing research on tissue-engineered models of the lymphatic system. Dr. Dixon received his Ph.D. in biomedical engineering while working in the Optical Biosensing Laboratory, where he developed an imaging system for measuring lymphatic flow and estimating wall shear stress in contracting lymphatic vessels.