Fig. 3. S. pyogenes are confined to sinuses within lymph nodes.

a–h Immunofluorescence staining of local draining inguinal (a–d) and distant draining axillary (e–h) lymph node cryosections from FVB/n mice prepared 3 h after intramuscular injection into the hindlimb with 10⁸ CFU of hypervirulent S. pyogenes (H1565); stained for S. pyogenes (green), podoplanin (red) and with DAPI (blue). White arrows highlight the location of S. pyogenes. Podoplanin staining highlights lymphatic endothelial cells in the subcapsular and medullary sinuses, as well as fibroblastic reticular cells in the cortex of the lymph node. Scale bars: 200 µm (a, e); 20 µm (b–d, f–h). Data are representative of five independent experiments. See also Supplementary Fig. 4a, b, and Supplementary Movies 6 and 7.