Fig. 3

Relationship between Siglec-15 and TIICs in LUAD in TMUCIH cohort (n = 189). A In TCGA database, Siglec-15 was positively correlated with TAMs and Tregs. B Siglec-15 in the TC was positively correlated with the density of CD8⁺ T cells, CD68⁺ TAMs, and CD4⁺FoxP3⁺ Tregs. C Siglec-15 in the MC was positively correlated with the density of CD8⁺ T cells, CD68⁺ TAMs, and CD4⁺FoxP3⁺ Tregs. D Representative mfIHC images of Siglec-15 and basic immune cell landscape in LUAD. E Based on tissue segmentation, the density of each immune cell population was calculated in the total, tumor, and stroma areas. F Patients with S15^H (n = 32) in the TC had more CD8⁺ T cells than those with S15^L (n = 157) in the stroma area, more CD68⁺ TAMs than those with S15^L in the total, tumor, or stroma areas. G Patients with S15^H (n = 53) in the MC had more CD8⁺ T cells than those with S15^L (n = 136) in the total and stroma areas, more CD68⁺ TAMs than those with S15^L in the total, tumor, or stroma areas