title: Characterisation and trophic functions of murine embryonic macrophages based upon the use of a Csf1r-EGFP transgene reporter.
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.
authors.affiliation: Institute for Molecular Bioscience and ARC Special Research Centre for Functional and Applied Genomics, University of Queensland, Brisbane, Queensland 4072, Australia.
authors.forename: Fiona
authors.initials: F
authors.lastname: Rae
authors.forename: Kyra
authors.initials: K
authors.lastname: Woods
authors.forename: Tedjo
authors.initials: T
authors.lastname: Sasmono
authors.forename: Naomi
authors.initials: N
authors.lastname: Campanale
authors.forename: Darrin
authors.initials: D
authors.lastname: Taylor
authors.forename: Dmitry A
authors.initials: DA
authors.lastname: Ovchinnikov
authors.forename: Sean M
authors.initials: SM
authors.lastname: Grimmond
authors.forename: David A
authors.initials: DA
authors.lastname: Hume
authors.forename: Sharon D
authors.initials: SD
authors.lastname: Ricardo
authors.forename: Melissa H
authors.initials: MH
authors.lastname: Little
mesh_terms: D000818:Animals; D001921:Brain / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D047108:Embryonic Development / Q000235:genetics / Q000502:physiology*; D005260:Female; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000235:genetics; D007668:Kidney / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D008168:Lung / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D008264:Macrophages / Q000166:cytology* / Q000378:metabolism*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D038081:Organogenesis / Q000235:genetics / Q000502:physiology; D011247:Pregnancy; D011401:Promoter Regions, Genetic; D016186:Receptor, Macrophage Colony-Stimulating Factor / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics
chemical_list: D011993:Recombinant Fusion Proteins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D016186:Receptor, Macrophage Colony-Stimulating Factor