IFNB1 and infection: Because OE-129WT cells secrete significantly higher amounts of C. muridarum-induced IFN-β starting as early as 2-3hr post-infection [43], we saw no significant differences in the candidate TJ protein transcription levels when the OE-129WT cells were pre-treated with 50U/ml of exogenous IFN-β (S3 and S4 Figs).