Tissue Engineering of Recellularized Small-Diameter Vascular Grafts

Abstract

A tissue-engineered small-diameter arterial graft would be of benefit to patients requiring vascular reconstructive procedures. Our objective was to produce a tissue-engineered vascular graft with a high patency rate that could withstand arterial pressures. Rat arteries were acellularized with a series of detergent solutions, recellularized by incubation with a primary culture of endothelial cells, and implanted as interposition grafts in the common femoral artery. Acellular grafts that had not been recellularized were implanted in a separate group of control animals. No systemic anticoagulants were administered. Grafts were explanted at 4 weeks for definitive patency evaluation and histologic examination; 89% of the recellularized grafts and 29% of the control grafts remained patent. Elastin staining demonstrated the preservation of elastic fibers within the media of the acellular grafts before implantation. Immunohistochemical staining of explanted grafts demonstrated a complete layer of endothelial cells on the lumenal surface in grafts that remained patent. Smooth muscle cells were observed to have repopulated the vessel walls. The mechanical properties of the matrix were comparable to native vessels. Such a strategy may present an alternative to autologous harvest of small vessels for use in vascular bypass procedures.

Scaffolding in tissue engineering: general approaches and tissue-specific considerations

“…Decellularized ECM from allogenic or xenogenic tissues for cell seeding Acellular ECM processed from allogenic or xenogenic tissues are the most nature-simulating scaffolds, which have been used in tissue engineering of many tissues including heart valves [62], vessels [15], nerves [44], tendon and ligament [56]. This scaffolding approach removes the allogenic or xenogenic cellular antigens from the tissues as they are the sources for immunogenicity upon implantation but preserves the ECM components, which are conserved among species and therefore well tolerated immunologically.…”

“…Decellularized ECM can be used for homologous functions when the decellularized ECM is used to replace an analogous structural tissue that has been damaged. An example is to decellularize vessels as allogenic vascular grafts [15,101]. Decellularized ECM can also be used for non-homologous functions when it is used for a purpose different from which it fulfills in its native state, or in a location of the body where such structural function does not normally occur.…”

Preparation of Ex Vivo–Based Biomaterials Using Convective Flow Decellularization

“…29 Following similar technologies, others have produced acellular liver stroma, 8 rat aortic valve, 24,26 and iliac artery. 30 Although the molecular details are not clear, some methods are more effective than others. For example, only partial decellularization was achieved when porcine heart valves were treated under continuous agitation in a 0.05% trypsin solution for <24 h followed by a 24 h PBS washing step.…”

Effect of cryopreservation on extracellular matrix proteins of vascular prostheses

“…Эти эффекты значительно ограничи-вают внедрение «химических» методик в практику предварительной обработки сосудов при импланта-ции. В нашей работе был предложен принципиально новый подход к созданию девитализированных со-судистых ксенопротезов малого диаметра, вклю-чающий предварительную обработку биоматериала с использованием физических факторов (заморажи-вание-отогрев, ионизирующее облучение) [2, 3, 7].Цель работы -изучение влияния низких темпе-ратур и ионизирующего облучения на структуру бел-ков внеклеточного матрикса (коллагена и эластина) при создании бесклеточных ксеногенных сосудистых скаффолдов.Внутригрудные артерии выделяли у беспородных половозрелых свиней с соблюдением правил биоэти-ки, утвержденных в ИПКиК, и в соответствии с When prosthetic repairing the small diameter vessels a question on the presence of adequate vascular substitute, scaffolds has still remained actual. Current methods of xenoartery devitalization are usually based on a continuous treatment of tissue with chemical agents.…”

“…Эти эффекты значительно ограничи-вают внедрение «химических» методик в практику предварительной обработки сосудов при импланта-ции. В нашей работе был предложен принципиально новый подход к созданию девитализированных со-судистых ксенопротезов малого диаметра, вклю-чающий предварительную обработку биоматериала с использованием физических факторов (заморажи-вание-отогрев, ионизирующее облучение) [2, 3, 7].…”