Washington National Primate Research Center, University of Washington 2 articles published in JoVE Neuroscience Convection Enhanced Delivery of Optogenetic Adeno-associated Viral Vector to the Cortex of Rhesus Macaque Under Guidance of Online MRI Images Karam Khateeb1,2, Devon J. Griggs2,3, Philip N. Sabes4, Azadeh Yazdan-Shahmorad1,2,3,4 1Departments of Bioengineering, University of Washington, 2Washington National Primate Research Center, 3Department of Electrical and Computer Engineering, University of Washington, 4Department of Physiology and Center for Integrative Neuroscience, University of California, San Francisco Here, we demonstrate magnetic resonance (MR)-guided convection enhanced delivery (CED) of viral vectors into the cortex as an efficient and simplified approach for achieving optogenetic expression across large cortical areas in the macaque brain. Medicine Laparoscopic Technique for Serial Collection of Liver and Mesenteric Lymph Nodes in Macaques Alexander S. Zevin1, Cassie Moats2, Drew May2, Solomon Wangari2, Charlene Miller1, Joel Ahrens2, Naoto Iwayama2, Megan Brown2, Debbie Bratt2, Nichole R. Klatt1, Jeremy Smedley2 1Department of Pharmaceutics, Washington National Primate Research Center, University of Washington, 2Division of Primate Resources, Washington National Primate Research Center, University of Washington Here, we describe a minimally invasive laparoscopic technique for serial sampling of liver and mesenteric lymph nodes (MLN) in macaques that allows for increased sampling frequency, and reduces the potential for surgical complications when compared to performing a laparotomy.