There are relationships between Th1/Th2/Th17/Treg/Th9/Th21 transcriptional factors with their cytokine lineages, where positive correlations (r ≥ 0.8) were found between RORC and IL17A, SPI1 and IL9, and BCL6 and IL21 in the experiment groups throughout the whole period of infection as shown in Table 2. Here, IL9 is linked to infection.