CD8A and glioblastoma: Recurrent GBM showed a strongly reduced expression of PD-L1 (de-novo GBM 20.8% PD-L1 positive cells, recurrent 7.6% PD-L1 positive cells) and also less lymphocytic infiltration (de-novo GBM 17.5% CD8 positive cells, recurrent 5.3% CD8 positive cells), Figure 3A-3B.