Figure 1.

M1-like macrophages infiltration was associated with PD-L1 expression in HCC cells (A) The relationship between enrichment of macrophages or M1 macrophages and PD-L1 expression in HCC samples from GEO database. (B) The distribution of CD68⁺ HLA-DR⁺ M1 macrophage in HCC tissue. Double immunohistochemical staining was performed by using anti-CD68 and anti-HLA-DR. The black arrow points to CD68⁺ macrophages while the white arrow points to CD68⁺ HLA-DR⁺ M1-like macrophages. (C) The association of PD-L1 expression with infiltration of M1 macrophages in HCC tissues. PD-L1 expression and M1-like macrophage distribution were detected in serial sections from the same HCC paraffin tissue. The number of CD68⁺ HLA-DR⁺ macrophages in the PD-L1⁺ region was higher than that in PD-L1⁻ region. (D) Positive and negative controls. A placental chorionic tissue was used as positive control (left). Negative controls were performed by omitting the primary antibodies (right). The data are presented as mean±SD. ** p < 0.01.