To investigate the in vivo expression of genes in which upregulation during infection was significantly impaired by CCR5-deficiency in the in vitro transcriptomic analysis, brain tissues from T. gondii-infected WT and CCR5KO mice were subjected to reverse transcription quantitative polymerase chain reaction (RT-qPCR) (Fig. 4, Additional file 6: Figure S3). Here, CCR5 is linked to infection.