title: Angiogenic and inflammatory response to biodegradable scaffolds in dorsal skinfold chambers of mice.
abstract: For tissue engineering, scaffolds should be biocompatible and promote neovascularization. Because little is known on those specific properties, we herein studied in vivo the host angiogenic and inflammatory response after implantation of commonly used scaffold materials. Porous poly(L-lactide-co-glycolide) (PLGA) and collagen-chitosan-hydroxyapatite hydrogel scaffolds were implanted into dorsal skinfold chambers of balb/c mice. Additional animals received cortical bone as an isogeneic, biological implant, while chambers of animals without implants served as controls. Angiogenesis and neovascularization as well as leukocyte-endothelial cell interaction and microvascular permeability were analyzed over 14 day using intravital fluorescence microscopy. PLGA scaffolds showed a slight increase in leukocyte recruitment compared to controls. This was associated with an elevation of microvascular permeability, which was comparable to that observed in isogeneic bone tissue. Of interest, PLGA induced a marked angiogenic response, revealing a density of newly formed capillaries almost similar to that observed in bone implants. Histology showed infiltration of macrophages, probably indicating resorption of the biomaterial. In contrast, hydrogel scaffolds induced a severe inflammation, as indicated by an approximately 15-fold increase of leukocyte-endothelial cell interaction and a marked elevation of microvascular permeability. This was associated by induction of apoptotic cell death within the surrounding tissue and a complete lack of ingrowth of newly formed microvessels. Histology confirmed adequate engraftment of PLGA and isogeneic bone but not hydrogel within the host tissue. PLGA scaffolds show a better biocompatibility than hydrogel scaffolds and promote vascular ingrowth, guaranteeing adequate engraftment within the host tissue.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Hannover Medical School, D-30625 Hannover, Germany. ruecker.martin@mh-hannover.de
authors.forename: Martin
authors.initials: M
authors.lastname: Rücker
authors.forename: Matthias W
authors.initials: MW
authors.lastname: Laschke
authors.forename: Dominik
authors.initials: D
authors.lastname: Junker
authors.forename: Carlos
authors.initials: C
authors.lastname: Carvalho
authors.forename: Alexander
authors.initials: A
authors.lastname: Schramm
authors.forename: Rolf
authors.initials: R
authors.lastname: Mülhaupt
authors.forename: Nils-Claudius
authors.initials: NC
authors.lastname: Gellrich
authors.forename: Michael D
authors.initials: MD
authors.lastname: Menger
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001672:Biocompatible Materials; D003872:Dermatitis / Q000503:physiopathology*; D005260:Female; D020100:Hydrogels; D019344:Lactic Acid; D051379:Mice; D008807:Mice, Inbred BALB C; D009389:Neovascularization, Pathologic / Q000503:physiopathology*; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers; D023822:Tissue Engineering
chemical_list: D001672:Biocompatible Materials; D020100:Hydrogels; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid