Article

Biofunctionalization of Biomaterials for Accelerated in Situ Endothelialization: A Review

Centre of Nanotechnology, Biomaterials and Tissue Engineering, UCL Division of Surgery & Interventional Science, University College London, London, United Kingdom.
Biomacromolecules (Impact Factor: 5.75). 11/2008; 9(11):2969-79. DOI: 10.1021/bm800681k
Source: PubMed

ABSTRACT The higher patency rates of cardiovascular implants, including vascular bypass grafts, stents, and heart valves are related to their ability to inhibit thrombosis, intimal hyperplasia, and calcification. In native tissue, the endothelium plays a major role in inhibiting these processes. Various bioengineering research strategies thereby aspire to induce endothelialization of graft surfaces either prior to implantation or by accelerating in situ graft endothelialization. This article reviews potential bioresponsive molecular components that can be incorporated into (and/or released from) biomaterial surfaces to obtain accelerated in situ endothelialization of vascular grafts. These molecules could promote in situ endothelialization by the mobilization of endothelial progenitor cells (EPC) from the bone marrow, encouraging cell-specific adhesion (endothelial cells (EC) and/or EPC) to the graft and, once attached, by controlling the proliferation and differentiation of these cells. EC and EPC interactions with the extracellular matrix continue to be a principal source of inspiration for material biofunctionalization, and therefore, the latest developments in understanding these interactions will be discussed.

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Available from: Gavin Jell, Jan 31, 2014
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    • "Bioactive scaffolds employed as a support for engineered tissue endothelialization are fabricated with synthetic or natural polymers and possess several properties useful for facilitating neovascularization [46]. Favorable materials might be also biofunctionalized in order to accelerate in situ endothelialization and provide a specific microenvironment mimicking the natural properties of the native tissue [47]. Examples of molecules that can be conjugated to the polymer material aimed at improving vessel formation are usually natural components of the extracellular matrix or their functional domains. "
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    Stem cell International 01/2014; 2014:434169. DOI:10.1155/2014/434169 · 2.81 Impact Factor
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    • "Whereas physiochemical modification can influence cell-material interactions through charge, topography, and attractive/repulsive forces due to hydrophobic and hydrophilic interactions [26]. Table 1: Summary of the various modification techniques currently employed for optimising blood-material interactions [26]. "
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    International Journal of Biomaterials 05/2012; 2012(4-5):707863. DOI:10.1155/2012/707863
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    • "Due to the high risk of bacterial and fungal infection throughout the entire in vitro culture (which takes up to 6 weeks from cell harvest to implantation of the engineered product), the process requires a cost-intensive infrastructure. Accordingly, ongoing research focuses on the development of facilitated spontaneous in vivo endothelialization of vascular implants [7] [8] [9] [10] [11]. Several pathways are conceivable to achieve endothelialization in vivo. "
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