title: Ongoing foreign body reaction to subcutaneous implanted (heparin) modified Dacron in rats.
abstract: Dacron-containing heart valve repair devices trigger chronic inflammation characterized by the presence of activated macrophages, foreign body giant cells, and capsule formation. Upon blood contact, proinflammatory proteins adsorb to the material and provide a substrate for monocyte binding and differentiation. Various heparin-coated polymers have been shown to reduce adsorption of proinflammatory proteins in vitro and in vivo. In this study, the effect of knitted, heparin-coated Dacron on the foreign body reaction was tested subcutaneously in rats. We hypothesized that the anti-inflammatory effect of heparin would reduce monocyte recruitment and differentiation and therefore limit the inflammatory reaction. An ongoing foreign body reaction, characterized by the presence of foreign body giant cells and high vascularization, was observed in uncoated as well as (heparin-)coated Dacron at up to 180 days of implantation. Also, a thin capsule was formed around each material up to this time. In conclusion, although heparin coatings might have an effect on the acute inflammatory response, we were not able to show a difference between heparin-coated and uncoated Dacron after 180 days' implantation in rats. Further research needs to be conducted to assess the difference in proinflammatory protein adsorption between the tested materials and the effect this has on the long-term foreign body reaction.
authors.affiliation: Medtronic Bakken Research Center BV, PO Box 1220, 6201 MP Maastricht, The Netherlands.
authors.forename: Paul H J
authors.initials: PH
authors.lastname: van Bilsen
authors.forename: Eliane R
authors.initials: ER
authors.lastname: Popa
authors.forename: Linda A
authors.initials: LA
authors.lastname: Brouwer
authors.forename: Judith
authors.initials: J
authors.lastname: Vincent
authors.forename: Catherine E
authors.initials: CE
authors.lastname: Taylor
authors.forename: Lou F M H
authors.initials: LF
authors.lastname: de Leij
authors.forename: Marc
authors.initials: M
authors.lastname: Hendriks
authors.forename: Marja J A
authors.initials: MJ
authors.lastname: van Luyn
mesh_terms: D000327:Adsorption; D000818:Animals; D020099:Coated Materials, Biocompatible / Q000009:adverse effects*; D005549:Foreign-Body Reaction / Q000139:chemically induced* / Q000473:pathology; D006350:Heart Valve Prosthesis / Q000009:adverse effects; D006493:Heparin; D020007:Implants, Experimental / Q000009:adverse effects*; D007249:Inflammation / Q000139:chemically induced / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000139:chemically induced; D011093:Polyethylene Terephthalates / Q000009:adverse effects*; D011506:Proteins / Q000378:metabolism; D051381:Rats
chemical_list: D020099:Coated Materials, Biocompatible; D011093:Polyethylene Terephthalates; D011506:Proteins; D006493:Heparin