Fig. 4
From: Tertiary lymphoid structures in diseases: immune mechanisms and therapeutic advances
Stroma cells initiate the formation of TLS. The sketch displayed that activation of fibroblasts and vessel endothelial cells (VECs) initiates the formation of TLS, leading to the production of chemokines and promoting the migration of lymphocytes. During this process, IL-7 mediates the positive feedback loop between the stroma cells and lymphocytes. HEVs promote the transport of lymphocytes. Chemokines stimulate the expression of LFA-1 on lymphocytes. It binds to adhesion molecules (ICAM) and stops the rolling of lymphocytes. Subsequently, they cross over the HEVs and are recruited to specific regions formed by fibroblasts
