CCL21 and prostate neoplasm: Given that LTα1β2 expression on B cell and dendritic cells is critical for stromal cells differentiation into FDC and blood vessels into HEV (63–66), we are assuming that activated B cells and dendritic cells are responsible for the morphological changes in stromal cells inside tumor-associated TLO (FDC, HEV) and for stimulating the local production of homeostatic chemokines (CCL19, CCL21, CXCL13) that are key in the attraction and local activation of immune cells in TLO embedded in prostate tumors (67, 68).