title: Protein polymer hydrogels: effects of endotoxin on biocompatibility.
abstract: Protein polymer-based hydrogels have shown potential for tissue engineering applications, but require biocompatibility testing for in vivo use. Enzymatically crosslinked protein polymer-based hydrogels were tested in vitro and in vivo to evaluate their biocompatibility. Endotoxins present in the hydrogel were removed by Trition X-114 phase separation. The reduction of endotoxins decreased TNF-α production by a macrophage cell line in vitro; however, significant inflammatory response was still present compared to collagen control gels. A branched PEG molecule and dexamethasone were added to the hydrogel to reduce the response. In vitro testing showed a decrease in the TNF-α levels with the addition of dexamethasone. In vivo implantations into the epididymal fat pad of C57/BL6 mice, however, indicated a decreased inflammatory mediated immune response with a hydrogel treated with both PEGylation and endotoxin reduction. This study demonstrates the importance of endotoxin testing and removal in determining the biocompatibility of biomaterials.
authors: Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL, USA.
authors: Liese N
authors: LN
authors: Beenken-Rothkopf
authors: Lindsay S
authors: LS
authors: Karfeld-Sulzer
authors: Xiaomin
authors: X
authors: Zhang
authors: Hermann
authors: H
authors: Kissler
authors: Sara A
authors: SA
authors: Michie
authors: Dixon B
authors: DB
authors: Kaufman
authors: Magali J
authors: MJ
authors: Fontaine
authors: Annelise E
authors: AE
authors: Barron
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001672:Biocompatible Materials; D002460:Cell Line; D004731:Endotoxins / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D011108:Polymers / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D004731:Endotoxins; D020100:Hydrogels; D011108:Polymers; D011506:Proteins