title: Mesenchymal Stem Cells after Polytrauma: Actor and Target.
abstract: Mesenchymal stem cells (MSCs) are multipotent cells that are considered indispensable in regeneration processes after tissue trauma. MSCs are recruited to damaged areas via several chemoattractant pathways where they function as "actors" in the healing process by the secretion of manifold pro- and anti-inflammatory, antimicrobial, pro- and anticoagulatory, and trophic/angiogenic factors, but also by proliferation and differentiation into the required cells. On the other hand, MSCs represent "targets" during the pathophysiological conditions after severe trauma, when excessively generated inflammatory mediators, complement activation factors, and damage- and pathogen-associated molecular patterns challenge MSCs and alter their functionality. This in turn leads to complement opsonization, lysis, clearance by macrophages, and reduced migratory and regenerative abilities which culminate in impaired tissue repair. We summarize relevant cellular and signaling mechanisms and provide an up-to-date overview about promising future therapeutic MSC strategies in the context of severe tissue trauma.
authors.affiliation: Department of Orthopaedic Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital of Ulm, 89081 Ulm, Germany.
authors.forename: Markus
authors.identifier: 0000-0003-2359-6516
authors.initials: M
authors.lastname: Huber-Lang
authors.affiliation: Department of Orthopaedic Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital of Ulm, 89081 Ulm, Germany.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Wiegner
authors.affiliation: Department of Anaesthesiology, Military Hospital Ulm, 89081 Ulm, Germany.
authors.forename: Lorenz
authors.initials: L
authors.lastname: Lampl
authors.affiliation: Orthopedic Department, Division for Biochemistry of Joint and Connective Tissue Diseases, University of Ulm, 89081 Ulm, Germany.
authors.forename: Rolf E
authors.initials: RE
authors.lastname: Brenner