title: Long- and short-term intravital imaging reveals differential spatiotemporal recruitment and function of myelomonocytic cells after spinal cord injury.
abstract: After spinal cord injury (SCI), resident and peripheral myelomonocytic cells are recruited to the injury site and play a role in injury progression. These cells are important for clearing cellular debris, and can modulate the retraction and growth of axons in vitro. However, their precise spatiotemporal recruitment dynamics is unknown, and their respective roles after SCI remain heavily debated. Using chronic, quantitative intravital two-photon microscopy of adult mice with SCI, here we show that infiltrating lysozyme M (LysM(+)) and resident CD11c(+) myelomonocytic cells have distinct spatiotemporal recruitment profiles, and exhibit changes in morphology, motility, phagocytic activity and axon interaction patterns over time. This study provides the first in vivo description of the influx of inflammatory and resident myelomonocytic cells into the injured spinal cord and their interactions with cut axons, and underscores the importance of precise timing and targeting of specific cell populations in developing therapies for SCI.
authors.affiliation: K. K. Fenrich: 3-88 Corbett Hall, Faculty of Rehab Medicine, University of Alberta, Edmonton, AB, Canada T6G 2G4. fenrich@ualberta.ca or G. Rougon: IBDML, Case 907 - Parc Scientifique de Luminy, 13009 Marseille Cedex 9, France.  genevieve.rougon@univ-amu.fr.
authors.forename: Keith K
authors.initials: KK
authors.lastname: Fenrich
authors.forename: Pascal
authors.initials: P
authors.lastname: Weber
authors.forename: Geneviève
authors.initials: G
authors.lastname: Rougon
authors.forename: Franck
authors.initials: F
authors.lastname: Debarbieux
mesh_terms: D000818:Animals; D001369:Axons / Q000473:pathology; D039521:CD11c Antigen / Q000235:genetics / Q000378:metabolism; D002465:Cell Movement; D051379:Mice; D008810:Mice, Inbred C57BL; D036641:Microscopy, Fluorescence, Multiphoton; D009000:Monocytes / Q000378:metabolism / Q000473:pathology / Q000502:physiology*; D009113:Muramidase / Q000235:genetics / Q000378:metabolism; D061848:Optical Imaging; D010587:Phagocytosis; D013119:Spinal Cord Injuries / Q000473:pathology* / Q000503:physiopathology
chemical_list: D039521:CD11c Antigen; D009113:Muramidase; C472450:lysozyme M, mouse
references.citation: J Physiol. 2012 Aug 15;590(16):3665-75
references.pmid: 22641787
references.citation: Proc Natl Acad Sci U S A. 2009 Jun 9;106(23):9459-64
references.pmid: 19470644
references.citation: Immunobiology. 2009;214(7):601-12
references.pmid: 19268389
references.citation: J Neurosci. 2011 Jan 19;31(3):944-53
references.pmid: 21248119
references.citation: J Neurol Sci. 2002 Oct 15;202(1-2):13-23
references.pmid: 12220687
references.citation: J Neurosci. 2008 Sep 17;28(38):9330-41
references.pmid: 18799667
references.citation: J Neurosci. 2009 Aug 12;29(32):9967-76
references.pmid: 19675231
references.citation: IEEE Trans Image Process. 1998;7(1):27-41
references.pmid: 18267377
references.citation: J Comp Neurol. 2008 Jun 10;508(5):687-710
references.pmid: 18386786
references.citation: Proc Natl Acad Sci U S A. 1988 Sep;85(17):6232-6
references.pmid: 3413093
references.citation: J Leukoc Biol. 2011 Apr;89(4):525-38
references.pmid: 21169519
references.citation: J Neurosci. 2004 Jul 21;24(29):6531-9
references.pmid: 15269264
references.citation: PLoS Med. 2009 Jul;6(7):e1000113
references.pmid: 19636355
references.citation: Nat Rev Immunol. 2011 Oct 25;11(11):788-98
references.pmid: 22025056
references.citation: Physiol Rev. 2011 Apr;91(2):461-553
references.pmid: 21527731
references.citation: Exp Neurol. 2013 Sep;247:282-5
references.pmid: 23333564
references.citation: Nat Immunol. 2004 Dec;5(12):1243-50
references.pmid: 15543150
references.citation: J Comp Neurol. 2011 Nov 1;519(16):3240-58
references.pmid: 21674488
references.citation: Brain. 2009 Feb;132(Pt 2):288-95
references.pmid: 18567623
references.citation: PLoS One. 2011;6(12):e27969
references.pmid: 22205935
references.citation: Neuron. 2000 Oct;28(1):41-51
references.pmid: 11086982
references.citation: Blood. 2000 Jul 15;96(2):719-26
references.pmid: 10887140
references.citation: J Immunol. 2008 Nov 1;181(9):5829-35
references.pmid: 18941170
references.citation: J Neuropathol Exp Neurol. 2012 Mar;71(3):180-97
references.pmid: 22318123