CCL2 and infection: The transcriptional level of macrophage chemokine CCL2 (MCP‐1) was also significantly upregulated on the 4th day (p = 0.0328), 5th day (p = 0.0004), 6th day (p = 0.0002), and 7th day (p = 0.0002) after infection (Figure 2D).