PDPN and neoplasm: Besides mediating LEC-DC interactions via C-type lectin-like receptor 2 (CLEC-2) [69], we herein found that podoplanin also regulates the adhesion of macrophages as lymphatic podoplanin deletion impaired macrophage adhesion to LEC monolayers in vitro and reduced the density of macrophages in medullary sinuses of tumor-draining LNs in vivo.