Trophoblast-derived CXCL16 induces M2 macrophage polarization that in turn inactivates NK cells at the maternal-fetal interface

Cell Mol Immunol. 2018 Dec;15(12):1038-1046. doi: 10.1038/s41423-018-0019-x. Epub 2018 Mar 27.

Abstract

Decidual macrophages (dMΦ) are distinct from the conventional macrophages present in other tissues and express M2 macrophage markers, but the molecular mechanisms of formation and the roles of M2 MΦ during pregnancy have not been completely elucidated. The crosstalk between decidual natural killer cells (dNK) and dMΦ plays an important role in the maintenance of maternal-fetal immune tolerance. Here, CXCL16 derived from first-trimester trophoblast cells induces the polarization of human M2 macrophages. The M2 MΦ polarized by CXCL16 exhibit decreased interleukin-15 production, which facilitates the inactivation of NK cells. The cytotoxicity of NK cells is attenuated by the CXCL16-polarized M2 MΦ. The data shown in the present study provide evidence to support the hypothesis that CXCL16 secreted by trophoblast cells is a key molecule involved in decidual M2 MΦ polarization, which in turn regulates the killing ability of NK cells, thereby contributing to the homeostatic and immune-tolerant milieu required for successful fetal development.

Keywords: CXCL16; NK cells; macrophage polarization; maternal–fetal interface; trophoblasts.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Communication
  • Cell Differentiation
  • Cells, Cultured
  • Chemokine CXCL16 / metabolism*
  • Cytokines / metabolism
  • Cytotoxicity, Immunologic
  • Decidua / immunology*
  • Female
  • Homeostasis
  • Humans
  • Immune Tolerance
  • Interleukin-15 / metabolism
  • Killer Cells, Natural / immunology*
  • Macrophages / immunology*
  • Maternal-Fetal Exchange
  • Pregnancy
  • Th2 Cells / immunology
  • Trophoblasts / immunology*

Substances

  • CXCL16 protein, human
  • Chemokine CXCL16
  • Cytokines
  • Interleukin-15