Interestingly, most of the hub-central genes in the green module, including CD3E (Mair et al., 2021), ZAP70 (Samten et al., 2009), CD4 (Boggiatto et al., 2021), IL2RA (Lu et al., 2011), CD247, LCK, CD3D, CD3G, PRKCQ (McLoughlin et al., 2021a), and ITK (Huang et al., 2020), were closely related to T-cell activation and the host immune response to infection with MTBC intracellular pathogens. This evidence concerns the gene CD4 and infection.