Both EIEC and S. flexneri caused increases in IL-8 secretion in a time-dependent manner; around 0.4 ng/ml at 0.5 h of infection, around 17 ng/ml at 1 h, around 28 ng/ml at 2 h, and around 42 ng/ml at 4 h of infection (Figure 6A). The gene discussed is CXCL8; the disease is infection.