Dynamic intravital imaging of cell-cell interactions in the lymph node Jens V. Stein, PhD, Santiago F. Gonzalez, PhD  Journal of Allergy and Clinical Immunology  Volume 139, Issue 1, Pages 12-20 (January 2017) DOI: 10.1016/j.jaci.2016.11.008 Copyright © 2016 American Academy of Allergy, Asthma & Immunology Terms and Conditions

Fig 1 Simplified cartoon showing immobilization of the mouse and the exposed popliteal LNs based on the model previously developed by Mempel et al.5 Journal of Allergy and Clinical Immunology 2017 139, 12-20DOI: (10.1016/j.jaci.2016.11.008) Copyright © 2016 American Academy of Allergy, Asthma & Immunology Terms and Conditions

Fig 2 Simplified figurative representation of a transversal cut of an LN. Fo, B cell follicle; IFA, interfollicular area; MM, medullary macrophage, SCS, subcapsular sinus. Journal of Allergy and Clinical Immunology 2017 139, 12-20DOI: (10.1016/j.jaci.2016.11.008) Copyright © 2016 American Academy of Allergy, Asthma & Immunology Terms and Conditions

Fig 3 A, Two-photon micrograph showing a transverse section of the medullary area where LNDCs (green) are associated with the conduit network (blue). B, Two-photon micrograph (left) and reconstruction (right) showing the relative position of the follicle (purple) with respect to the SSM population (red) and the LN capsule (blue). C, Two-photon micrograph showing the close interaction between an FDC in the follicle (red) and a collagen fiber (blue). Coll, Collagen; Fo, follicle; IFA, interfollicular area. Journal of Allergy and Clinical Immunology 2017 139, 12-20DOI: (10.1016/j.jaci.2016.11.008) Copyright © 2016 American Academy of Allergy, Asthma & Immunology Terms and Conditions

Fig 4 A, Intravital 2-photon snapshot showing the position of the SSM (red) with respect to other areas of the LNs. B, Schematic representation of the interaction between the SSMs and conduits in the subcapsular sinus. C, Electron micrograph showing 2 SSMs closely interacting with conduits generated in the subcapsular sinus area. Fo, Follicle; IFA, interfollicular area; Med, medulla. Journal of Allergy and Clinical Immunology 2017 139, 12-20DOI: (10.1016/j.jaci.2016.11.008) Copyright © 2016 American Academy of Allergy, Asthma & Immunology Terms and Conditions

Fig 5 Lymphocyte circulation and interaction in the LNs. Lymphocyte recruitment (1) is associated with HEVs located in the interfollicular region (IFR). Once in the LN, lymphocyte movement is associated with conduits secreted by fibroblast that transport specific chemokines that direct the T cells and the B cells toward their respective areas (2 and 3, respectively). DCs from the draining tissue (mDC) or resident in the LNs (LNDC) migrate to this area on activation and interact with the conduit network, maximizing the possibilities to encounter T cells (4). According to the time of interaction, T cells interact with DCs in 3 phases. Journal of Allergy and Clinical Immunology 2017 139, 12-20DOI: (10.1016/j.jaci.2016.11.008) Copyright © 2016 American Academy of Allergy, Asthma & Immunology Terms and Conditions