Cigarette smoke extract interferes with placenta macrophage functions: A new mechanism to compromise placenta functions?

The success of pregnancy depends on the maternal immune system's ability to promote tolerance and host defense. This equilibrium is compromised in inflammatory and infectious impairment of placenta. Smoking during pregnancy exposes the fetus to severe complications which might result from an alteration in placenta macrophages (pM phi) functions. In this study, we assessed the effect of cigarette smoke extract (CSE) on the functions of third trimester pM phi s.CSE inhibited particles uptake and the formation of multinucleated giant cells, a recently reported property of pM phi s based on their ability to fuse in vitro. These alterations were associated with a CSE-induced abnormal activation of pM phi s, which was characterized by an increased release of TNF, interleukin (IL)-33, and decreased IL-6 and IL-10 release. Furthermore, CSE enhanced the expression of metalloproteinase genes known to be involved in tissue remodeling. This effect of CSE on pM phi s was specific because CSE affected circulating monocytes in a different way. Finally, we showed that nicotine affected in part the functional properties of pM phi s. Taken together, these results showed that CSE modulated the functional activity of pM phi s, which may compromise pregnancy. (C) 2018 Elsevier Inc. All rights reserved.