Methods in Molecular Biology (2022) 2436: 205–222

DOI 10.1007/7651_2021_417

© Springer Science+Business Media, LLC 2021

Published online: 10 September 2021

Bacterial Nanocellulose-Based Grafts for Cell Colonization

Studies: An In Vitro Bioreactor Perfusion Model

Max Wacker, Jan Riedel, Priya Veluswamy, Maximilian Scherner,

Jens Wippermann, Heike Walles, and Jo¨rn Hu¨lsmann

Abstract

With the aging population, the demand for artificial small diameter vascular grafts is constantly increasing,

as the availability of autologous grafts is limited due to vascular diseases. A confluent lining with endothelial

cells is considered to be a cornerstone for long-term patency of artificial small diameter grafts. We use

bacterial nanocellulose off-the-shelf grafts and describe a detailed methodology to study the ability of these

grafts to re-colonize with endothelial cells in an in vitro bioreactor model. The viability of the constructs

generated in this process was investigated using established cell culture and tissue engineering methods,

which includes WST-1 proliferation assay, AcLDL uptake assay, lactate balancing and histological charac-

terization. The data generated this straight forward methodology allow an initial assessment of the principal

prospects of success in forming a stable endothelium in artificial vascular prostheses.

Keywords Bacterial cellulose, Cell seeding, Endothelialization, Perfusion bioreactor, Small diameter

vascular grafts, Vascular tissue engineering

1

Introduction

Due to the aging population and the resulting limited availability of

autologous vessels, there is an increasing demand for small caliber

artificial grafts in the fields of cardiac and vascular surgery [1]. The

development of small caliber vascular grafts poses a challenge to

prosthesis developers. The patency rate of the grafts remains to be

the main criterion for their successful application in vivo, as this

directly influences morbidity and survival in the use, for e.g., coro-

nary artery bypass graft [2]. The failure of grafts when implanted

in vivo is especially characterized by two mechanisms; (1) narrowing

of the lumen by intimal hyperplasia and (2) thrombus formation as

a consequence of graft surface and blood interactions [3]. In vivo,

the local regulation of these processes is mainly regulated by the

vascular endothelium [4]. Therefore, the process of endothelializa-

tion is subject of current research in vascular tissue engineering and

Max Wacker and Jan Riedel contributed equally to this work.

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