CXCL13 and rheumatoid arthritis: The recruitment of L-selectin+ dendritic cells, B-cells and CD45RA T-cells to RA synovium correlates with the expression of homing chemokines such as CXCL13, CCL19 and CCL21, and the latter partially colocalizes to MECA-79 positive HEV [3,38,39].