Figure 4.

Nivolumab-dependent changes of tumor infiltrating immune cell densities and proliferation rates. Tissue slices of clear cell renal cell carcinoma (ccRCC) were immunohistochemically stained for Ki67-PD1, Ki67-CD3, and Ki67-CD8 after 24 h of cultivation with increasing concentrations of nivolumab. Three representative reaction patterns to nivolumab treatment are shown: (A) pattern A (tumor 3) with nivolumab-dependent increased tumor infiltrating T-cells, (B) pattern B (tumor 5) with nivolumab-dependent decreased tumor infiltrating T-cells, and (C) pattern C (tumor 7) without nivolumab-dependent changes of tumor infiltrating T-cells. Data are given as mean ± standard deviation. For statistical analysis the one-way analysis of variance or the Kruskal–Wallis test with appropriate post hoc tests were used. p-values were corrected with the Bonferroni method. *: p < 0.05.