Hyaluronic Acid Oligomer Immobilization as an Angiogenic Trigger for the Neovascularization of TE Constructs

Publication year: 2021
Authors: A.L. Silva 1,2, P.S. Babo 1,2, M.T. Rodrigues 1,2, A.I. Gonçalves 1,2, R. Novoa-Carballal 1,2, R.A. Pires 1,2, J. Rouwkema 3, R.L. Reis 1,2, M.E.Gomes 1,2

1 - 3B’s Research Group, I3Bs − Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, 4805-017 Barco, Guimarães, Portugal
2 - ICVS/3B’s−PT Government Associate Laboratory, Braga/Guimarães 4710-057, Portugal
3 - Department of Biomechanical Engineering, Faculty of Engineering Technology, University of Twente, 7500 AE Enschede, The Netherlands

Published in: ACS Applied Bio Materials, 2021, Vol. 4 (8), p. 6023–6035
doi: 10.1021/acsabm.1c00291

Tissue engineered (TE) substitutes of clinically relevant sizes need an adequate vascular system to ensure function and proper tissue integration after implantation. However, the predictable vascularization of TE substitutes is yet to be achieved. Molecular weight variations in hyaluronic acid (HA) have been pointed to trigger angiogenesis. Thus, this study investigates HA oligomer immobilization as a promoter for TE construct vascularization. As a proof-of-concept, the surface of methacrylated gelatin (GelMA) hydrogels were functionalized with high molecular weight (HMW; 1.5 to 1.8 MDa) and low molecular weight (LMW; < 10 kDa) HA, previously modified with aldehyde groups to enable the immobilization through Schiff’s base formation. The ability of A-HA to bind amine-presenting surfaces was confirmed by Surface Plasmon Resonance (SPR). Human Umbilical Vein Endothelial Cells (HUVECs) seeded over hydrogels functionalized with LMW HA showed higher proliferation and expression of angiogenic markers (KDR and CD31), than those grown in HMW HA conjugated- or plain surfaces, in line with the activation of HA ERK1/2 mediated downstream signaling. Moreover, when cocultured with human dental pulp cells (hDPCs) encapsulated into the GelMA, an increase in endothelial cell migration was observed for the LMW HA functionalized formulations. Overall LMW HA functionalization enhanced endothelial cell response showing potential as an angiogenesis inducer for TE applications.

MP-SPR keywords: amine coupling, Au sensor slide, immobilization kinetics