IL-17A and chemokines including CXCLs attract myeloid cells such as neutrophils to the infection site and activate matrix metalloproteinase, which results in the recruitment of more inflammatory cells such as Th1 and Th17 cells and, as a consequence, a positive loop in amplifying inflammatory reactions (Corrigan et al., 2011; Liu et al., 2016; Abdollahi et al., 2020d). The gene discussed is IL17A; the disease is infection.