Characterisation and Trophic Functions of Murine Embryonic Macrophages Based Upon the Use of a Csf1r-EGFP Transgene Reporter

Dev Biol. 2007 Aug 1;308(1):232-46. doi: 10.1016/j.ydbio.2007.05.027. Epub 2007 May 25.

Abstract

All solid organs contain resident monocyte-derived cells that appear early in organogenesis and persist throughout life. These cells are critical for normal development in some organs. Here we report the use of a previously described transgenic line, with EGFP driven by the macrophage-restricted Csf1r (c-fms) promoter, to image macrophage production and infiltration accompanying organogenesis in many tissues. Using microarray analysis of FACS-isolated EGFP-positive cells, we show that fetal kidney, lung and brain macrophages show similar gene expression profiles irrespective of their tissue of origin. EGFP-positive cells appeared in the renal interstitium from 12 days post coitum, prior to nephrogenesis, and maintain a close apposition to renal tubules postnatally. CSF-1 added to embryonic kidney explants increased overall renal growth and ureteric bud branching. Expression profiling of tissue macrophages and of CSF-1-treated explants showed evidence of the alternate, pro-proliferative (M2) activation profile, including expression of macrophage mannose receptor (CD206), macrophage scavenger receptor 2 (Msr2), C1q, CD163, selenoprotein P, CCL24 and TREM2. This response has been associated with the trophic role of tumour-associated macrophages. These findings suggest a trophic role of macrophages in embryonic kidney development, which may continue to play a similar role in postnatal repair.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / cytology
  • Brain / embryology
  • Brain / metabolism
  • Embryonic Development / genetics
  • Embryonic Development / physiology*
  • Female
  • Gene Expression Profiling
  • Gene Expression Regulation, Developmental
  • Genes, Reporter
  • Green Fluorescent Proteins / genetics
  • Kidney / cytology
  • Kidney / embryology
  • Kidney / metabolism
  • Lung / cytology
  • Lung / embryology
  • Lung / metabolism
  • Macrophages / cytology*
  • Macrophages / metabolism*
  • Male
  • Mice
  • Mice, Transgenic
  • Organogenesis / genetics
  • Organogenesis / physiology
  • Pregnancy
  • Promoter Regions, Genetic
  • Receptor, Macrophage Colony-Stimulating Factor / genetics
  • Recombinant Fusion Proteins / genetics

Substances

  • Recombinant Fusion Proteins
  • enhanced green fluorescent protein
  • Green Fluorescent Proteins
  • Receptor, Macrophage Colony-Stimulating Factor