Evidence for a dynamic role for mononuclear phagocytes during endometrial repair and remodelling

Sci Rep. 2016 Nov 9:6:36748. doi: 10.1038/srep36748.

Abstract

In women, endometrial breakdown, which is experienced as menstruation, is characterised by high concentrations of inflammatory mediators and immune cells which account for ~40% of the stromal compartment during tissue shedding. These inflammatory cells are known to play a pivotal role in tissue breakdown but their contribution to the rapid scarless repair of endometrium remains poorly understood. In the current study we used a mouse model of menstruation to investigate dynamic changes in mononuclear phagocytes during endometrial repair and remodelling. Menstruation was simulated in MacGreen mice to allow visualisation of CSF1R+ mononuclear phagocytes. Immunohistochemistry revealed dynamic spatio-temporal changes in numbers and location of CSF1R-EGFP+ cells and Ly6G+ neutrophils. Flow cytometry confirmed a striking increase in numbers of GFP+ cells during repair (24 h): influxed cells were 66% F4/80+Gr-1+ and 30% F4/80-Gr-1+. Immunostaining identified distinct populations of putative 'classical' monocytes (GFP+F4/80-), monocyte-derived macrophages (GFP+F4/80+) and a stable population of putative tissue-resident macrophages (GFP-F4/80+) localised to areas of breakdown, repair and remodelling respectively. Collectively, these data provide the first compelling evidence to support a role for different populations of monocytes/macrophages in endometrial repair and provide the platform for future studies on the role of these cells in scarless healing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Endometrium / cytology
  • Endometrium / metabolism*
  • Estrus / physiology*
  • Female
  • Macrophages / cytology
  • Macrophages / metabolism*
  • Mice, Transgenic
  • Neutrophils / cytology
  • Neutrophils / metabolism*