Fig. 1.

Histology of the lymph node. Hematoxylin and eosin (H.E.) staining and immunohistochemistry of PD-L1 (clone 22C3, DAKO, Glostrup, Denmark), CD8 (clone C8/144B, Nichirei, Tokyo, Japan), Iba1 (clone NCNP27, WAKO, Tokyo, Japan), CD163 (clone 10D6, Abcam, Cambridge, UK), and CD169 (clone SP216, Abcam Cambridge, UK) are shown. The immunohistochemistry procedures were described in a previous report. ¹³ Subcapsular and medullary sinus macrophages that were positive for Iba1, CD163, and CD169 were also positive for PD-L1. Dendritic cells that were positive for Iba1 and negative for CD163 and CD169 strongly expressed PD-L1. CD8-positive T-cells were more commonly detected in areas in which antigen-presenting cells were seen.