Secreted Endothelial Cell Factors Immobilized on Collagen Scaffolds Enhance the Recipient Endothelial Cell Environment.

Charlotte Hamilton,Anthony Callanan

doi:10.1089/biores.2016.0003

Abstract

Strategies to design novel vascular scaffolds are a continuing aim in tissue engineering and often such designs encompass the use of recombinant factors to enhance the performance of the scaffold. The established use of cell secretion utilized in feeder systems and conditioned media offer a source of paracrine factors, which has potential to be used in tissue-engineered (TE) scaffolds. Here we utilize this principle from endothelial cells (ECs), to create a novel TE scaffold by harnessing secreted factors and immobilizing these to collagen scaffolds. This research revealed increased cellular attachment and positive angiogenic gene upregulation responses in recipient ECs grown on these conditioned scaffolds. Also, the conditioning method did not affect the mechanical structural integrity of the scaffolds. These results may advocate the potential use of this system to improve vascular scaffolds' in vivo performance. In addition, this process may be a future method utilized to improve other tissue engineering scaffold therapies.

Highlights

A continuing challenge faced in vascular tissue engineering is how to improve treatments for cardiovascular disease and other such arterial conditions
The protein released into the phosphate-buffered saline (PBS) group had an average concentration of 0.32 lg/lL, while in the Basal media (BM) group this was higher at 0.35 lg/lL, due to the additional components present within the media
The adjusted BM (ABM) group had the largest concentration at 0.4 lg/lL, with the presence of endothelial cell-secreted factors (ECSFs) in the media

Summary

Introduction

A continuing challenge faced in vascular tissue engineering is how to improve treatments for cardiovascular disease and other such arterial conditions. Some of the most common types of scaffold are collagen based[11,12,13] and have been shown to promote cell attachment, migration, proliferation, differentiation, and ECM production during remodeling and regeneration.[14] More recently, they have incorporated growth factors and proteins such as vascular endothelial growth factor (VEGF)[15,16] and angiopoietin-1 (Ang1).[17,18] The use of growth factors and proteins has predominately focused on the concentration and release kinetics of these factors, whether they are designed to be retained within the scaffold[19,20] or released.[21,22,23] Mainly, the purpose is to enhance the cell functionality, and contact and interact with the in vivo tissue.[24]

Methods

Results

Conclusion