title: In vivo imaging reveals a pioneer wave of monocyte recruitment into mouse skin wounds.
abstract: The cells of the mononuclear phagocyte system are essential for the correct healing of adult skin wounds, but their specific functions remain ill-defined. The absence of granulation tissue immediately after skin injury makes it challenging to study the role of mononuclear phagocytes at the initiation of this inflammatory stage. To study their recruitment and migratory behavior within the wound bed, we developed a new model for real-time in vivo imaging of the wound, using transgenic mice that express green and cyan fluorescent proteins and specifically target monocytes. Within hours after the scalp injury, monocytes invaded the wound bed. The complete abrogation of this infiltration in monocyte-deficient CCR2(-/-) mice argues for the involvement of classical monocytes in this process. Monocyte infiltration unexpectedly occurred as early as neutrophil recruitment did and resulted from active release from the bloodstream toward the matrix through microhemorrhages rather than transendothelial migration. Monocytes randomly scouted around the wound bed, progressively slowed down, and stopped. Our approach identified and characterized a rapid and earlier than expected wave of monocyte infiltration and provides a novel framework for investigating the role of these cells during early stages of wound healing.
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI), 91 Bd de l'hôpital, Paris, France; INSERM, U1135, CIMI, 91 Bd de l'hôpital, Paris, France; CNRS, ERL, CIMI, 91 Bd de l'hôpital, Paris, France.
authors.forename: Mathieu P
authors.initials: MP
authors.lastname: Rodero
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI), 91 Bd de l'hôpital, Paris, France; INSERM, U1135, CIMI, 91 Bd de l'hôpital, Paris, France; CNRS, ERL, CIMI, 91 Bd de l'hôpital, Paris, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Licata
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI), 91 Bd de l'hôpital, Paris, France; INSERM, U1135, CIMI, 91 Bd de l'hôpital, Paris, France; CNRS, ERL, CIMI, 91 Bd de l'hôpital, Paris, France.
authors.forename: Lucie
authors.initials: L
authors.lastname: Poupel
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI), 91 Bd de l'hôpital, Paris, France; INSERM, U1135, CIMI, 91 Bd de l'hôpital, Paris, France; CNRS, ERL, CIMI, 91 Bd de l'hôpital, Paris, France.
authors.forename: Pauline
authors.initials: P
authors.lastname: Hamon
authors.affiliation: The University of Queensland, UQ Centre for Clinical Research, Brisbane, QLD, Australia; The University of Queensland, UQ Diamantina Institute, Translational Research Institute, Woolloongabba, QLD, Australia.
authors.forename: Kiarash
authors.initials: K
authors.lastname: Khosrotehrani
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI), 91 Bd de l'hôpital, Paris, France; INSERM, U1135, CIMI, 91 Bd de l'hôpital, Paris, France; CNRS, ERL, CIMI, 91 Bd de l'hôpital, Paris, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Combadiere
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CR7, Centre d'Immunologie et des Maladies Infectieuses (CIMI), 91 Bd de l'hôpital, Paris, France; INSERM, U1135, CIMI, 91 Bd de l'hôpital, Paris, France; CNRS, ERL, CIMI, 91 Bd de l'hôpital, Paris, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Boissonnas
mesh_terms: D000818:Animals; D002634:Chemotaxis, Leukocyte; D004195:Disease Models, Animal; D051379:Mice; D018345:Mice, Knockout; D036641:Microscopy, Fluorescence, Multiphoton; D009000:Monocytes / Q000276:immunology* / Q000473:pathology*; D020556:Neutrophil Infiltration; D012867:Skin / Q000276:immunology* / Q000473:pathology*; D014945:Wound Healing; D014947:Wounds and Injuries / Q000276:immunology* / Q000473:pathology*