Endothelial cell seeding of polytetrafluoroethylene vascular grafts in humans: A preliminary report

Abstract

The importance of initial human trials with autologous endothelial seeding lies not only in the implementation of a promising idea but also in the fact that canine data are only partially applicable to humans. The surface area of jugular veins in humans is much smaller than in dogs and considerably longer grafts are needed. Moreover, the reproductive capacity of adult human endothelial cells under in vivo conditions, which probably determines the success of seeding more than the seeding density, is also uncertain. Therefore the efficiency of autologous endothelial seeding in humans was investigated in 18 patients undergoing distal femoropopliteal bypass surgery. The average surface area of the jugular veins was 4.9 +/- 1.7 cm2 with an average cell yield of 32.6 +/- 18.0 x 10(4). The mean number of seeded cells per square centimeter of graft surface was 3.1 x 10(3). In a follow-up extending for 14 weeks, plasma levels of platelet factor 4 and beta-thromboglobulin as well as the platelet function in the whole blood aggregometer showed significantly better results in the seeded group. Plasma thromboxane B2, uptake and survival of indium 111-labeled platelets, and Doppler ultrasound investigations also favored the seeded group, but the results were statistically insignificant. No difference at all was found for the platelet dense granule compounds, releasable adenosine triphosphate and platelet serotonin. Thus our findings did not indicate the development of a closed endothelialized surface after 14 weeks, which is a period three times as long as the one required for confluent endothelial cell coverage in dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Molecular Understanding of Endothelial Cell and Blood Interactions with Bacterial Cellulose: Novel Opportunities for Artificial Blood Vessels

“…Many different materials have been investigated for biomaterial applications. They can be divided into natural materials, i.e., collagen (Weinberg & Bell, 1986;L'Heureux et al, 1998); fibrin (Cummings et al, 2004;Kumar & Krishnan, 2002); hyaluronic acid (Remuzzi et al, 2004;Turner et al, 2004); silk fibroin (Zhang et al, 2009) and BC (Backdahl et al, 2006;Klemm et al, 2001;Bodin et al, 2007;Fink et al, 2010)) and synthetic polymers, i.e., polyglycolic acid (PGA) (Niklason et al, 1999;McKee et al, 2003), polyethylene terephthalate (PET) (Sharefkin et al, 1983;Herring et al, 1984) and ePTFE (Zilla et al, 1987;Meinhart et al, 2005). The required properties for biomaterials vary with cell type, implantation site and strategy for tissue formation.…”

Multifaceted prospects of nanocomposites for cardiovascular grafts and stents

“…It was found that the POSS-based nanocomposite enhanced the cell adhesion property of the grafts in comparison to the existing silicone copolymers. 50,53,54 This is because the nanocages occupy a very small volume inside the polymer thereby providing a larger surface area to PU, which results in enhanced endothelialization. In addition, this structural arrangement of the nanocage provides a greater degree of polarity to the polymer thus making it more hydrophobic.…”

“…50 In a work done by Solouk et al 51 an in vitro study was carried out on human umbilical vein endothelial cells (HUVECs). The nanocomposite efficacy, safety, and compatibility with in vitro cell cultures was investigated.…”

Defining the potential for cell therapy for vascular disease using animal models

“…Nonetheless, multiple sources of mature endothelial cells exist. Venous endothelium has been harvested and used to populate biomaterial or synthetic vascular grafts (Herring et al, 1978;Graham et al, 1979;Belden et al, 1982;Noishiki et al, 1990a;Noishiki et al, 1990b;Noishiki et al, 1992), although endothelial cells may be quite limited in these settings (Zilla et al, 1987).…”

“…Nonetheless, multiple sources of mature endothelial cells exist. Venous endothelium has been harvested and used to populate biomaterial or synthetic vascular grafts (Herring et al, 1978;Graham et al, 1979;Belden et al, 1982;Noishiki et al, 1990a;Noishiki et al, 1990b;Noishiki et al, 1992), although endothelial cells may be quite limited in these settings (Zilla et al, 1987).Adipose tissue contains two potent sources of endothelial cells, namely resident microvascular endothelial cells and adipose-derived stromal cells (Miranville et al, 2004;Planat-Benard et al, 2004;Fraser et al, 2006;Wosnitza et al, 2007;Traktuev et al, 2008). In humans, the former may be defined as CD34+/CD45-cells that express CD31 and CD144.…”