CCR7 (C-C Motif Chemokine Receptor 7): CCR7 is a key receptor in the immune system that guides the migration of T cells and dendritic cells to lymphoid tissues. Its interaction with the ligands CCL19 and CCL21 is essential for coordinating adaptive immune responses and maintaining immune surveillance. Dysregulation of CCR7 has been linked to autoimmune diseases and cancers, making it an important target in immunotherapy and cancer treatment research.