IL6 and infection: However, the differential expression of TGF-β was not observed at 24 and 72 h p.i., and IL-6 and IL-6R were downregulated at 72 h p.i. Because these polarizing cytokines are produced at the initial stage of infection and the differentiation process of specific T helper cells takes approximately 3 days in vitro37, further analysis with DEGs at earlier time points (ex.