Beth Israel Deaconess Medical Center, Harvard Medical School 3 articles published in JoVE Bioengineering A Passive Ankle Dorsiflexion Testing System for an In Vivo Model of Overuse-induced Tendinopathy Pooja H. Chainani1,2, Patrick M. Williamson1,2, Diana Yeritsyan1, Kaveh Momenzadeh1, Nadim Kheir1, Joseph P. DeAngelis1,3, Arun J. Ramappa1,3, Ara Nazarian1,2,3,4 1Musculoskeletal Translational Innovation Initiative, Carl J. Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, 2Mechanical Engineering Department, Boston University, 3Carl J. Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, 4Department of Orthopaedic Surgery, Yerevan State Medical University This protocol presents a testing system used to induce quantifiable and controlled fatigue injuries in a rat Achilles tendon for an in-vivo model of overuse-induced tendinopathy. The procedure consists of securing the rat's ankle to a joint actuator that performs passive ankle dorsiflexion with a custom-written MATLAB script. Immunology and Infection Flow Cytometric Analysis for Identification of the Innate and Adaptive Immune Cells of Murine Lung Anthos Christofides1,2, Carol Cao1,2,3, Rinku Pal1,2, Halil I. Aksoylar1,2, Vassiliki A. Boussiotis1,2 1Division of Hematology-Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, 2Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 3Harvard College In this study, we present an effective and reproducible protocol to isolate the immune populations of the murine respiratory system. We also provide a method for the identification of all innate and adaptive immune cells that reside in the lungs of healthy mice, using a 9-color-based flow cytometry panel. Biology Quantification of Cellular Densities and Antigenic Properties using Magnetic Levitation Lauren Thompson1, Brandy Pinckney1, Shulin Lu2, Mark Gregory2, John Tigges1, Ionita Ghiran2 1Nano Flow Core Facility, Beth Israel Deaconess Medical Center, Harvard Medical School, 2Department of Medicine, Division of Allergy and Inflammation, Beth Israel Deaconess Medical Center This paper describes a magnetic levitation-based method that can specifically detect the presence of antigens, either soluble or membrane-bound, by quantifying changes in the levitation height of capture beads with fixed densities.