Investigating the role of interleukin-17A on cytokines production by macrophages in response to bacterial infections

Abstract

Interleukin-17A (IL-17A) has been shown to associate with a variety of infection diseases. In this study, we investigate whether IL-17A affects cytokines production of human peripheral blood-derived macrophages during Mycobacteriun bovis BCG or Klebsiella pneumoniae infection. We observed that IL-17A-treated macrophages exhibited suppressed productions of TNF-α and IL-6 in response to BCG infection. The reduction of cytokines production was not associated with cell death. On the other hand, IL-17A promoted TNF-α and IL-6 production by macrophages during K. pneumoniae infection. Furthermore, IL-17A did not affect TNF-α production induced by LPS and Pam3 Cys, which are TLR4 and TLR2 agonists, respectively. The data suggest that the differential regulation of cytokines production by IL-17A requires whole bacterium infection.