The role of chemokines in adjusting the balance between CD4 + effector T cell subsets and FOXp3-negative regulatory T cells

Chemokines are small (~ 8–14 kDa) structurally-related chemotactic cytokines that regulate cell trafficking through interactions with specific seven-trans membrane, G protein-coupled receptors (GPCRs). One of the important features of G protein-coupled receptors (GPCRs) is their ability to transmit diverse signaling cascades upon binding different ligands. The current review focuses on the interplay between three ligands: CXCL9, CXCL10 and CXCL11 binding the same receptor (CXCR3) on CD4 + T cells, yet direct different signaling cascades to shape T cell mediated immunity. The review brings about a new concept regarding the biological activities of chemokines in shaping CD4 + T cell immunity, and also a new approach for applying chemokine based therapy of autoimmune diseases.