Therefore, the down-regulation of these proinflammatory cytokines and chemokine by treatment with ECGC in PRRSV infected cells was because ECGC was found to reverse the increased expression of mRNA transcripts encoding TNF-α, IL-6 and IL-8 after PRRSV infection and thereby inhibit viral replication and propagation during the early stages of viral infection (Ge et al., 2018). Here, TNF is linked to viral infectious disease.