CXCL13 and infection: The RT-qPCR results showed that, except for the CXCL13 and MMP7, all shared seven genes were upregulated by about 12.4-fold on average in chicken embryo lungs after infection (Figure 8c), while in MG-infected chick lung tissue, all eight genes were upregulated by about 5.4-fold on average, except for IL20RA (Figure 8e).