JAG1 and infection: The blood vessels from the infection group showed a decrease in RBP-J mRNA expression compared to the control group (p < 0.001), as shown in Figure 5E. JAG1, a ligand in the Notch signaling pathway, was found to be downregulated at mRNA levels after G. parasuis infection (p < 0.001), as shown in Figure 5I, which could further enhance the Notch pathway activation.