CXCL8 and rheumatoid arthritis: Finally, RA synovial tissues were characterized by the presence of nurse-like cells (NLCs), having the ability to promote antibody production by B cells, to protect lymphocytes from apoptosis, and to secrete a large number of cytokines and chemokines, i.e., monocyte chemotactic protein1 (MCP-1), IL-8, and other chemokines (16), as well as IL-6, IL-7, GM-CSF, and granulocyte colony-stimulating factor (G-CSF) (17), promoting the accumulation and activation of monocytes and lymphocytes, including B cells (18).