Page 504 - IJB-10-6

International

Journal of Bioprinting

RESEARCH ARTICLE
Collagen bioinks redefined: Optimizing ionic

strength and growth factor delivery for
cartilage tissue engineering

Murad Redzheb * , Yordan Sbirkov 2,3† id , Atanas Valev 1 id , Vasil Dzharov 3 id ,
1† id
Hristi Petrova , Tatyana Damyanova 2 id , Ani Georgieva 1,4 id , and
1
Victoria Sarafian 2,3 id
1 MatriChem Ltd., Sofia, Bulgaria
2 Department of Medical Biology, Faculty of Medicine, Medical University of Plovdiv, Plovdiv,
Bulgaria
3 Department of Molecular and Regenerative Medicine, Research Institute at Medical University of
Plovdiv (RIMU-Plovdiv), Plovdiv, Bulgaria
4 Section Pathology, Institute of Experimental Morphology, Pathology and Anthropology with
Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria

Abstract
† These authors contributed equally
to this work.
Tissue engineering of hyaline cartilage for regenerative medicine and the
*Corresponding authors: treatment of osteoarthritis has advanced significantly over the past decade,
Murad Redzheb driven by developments in 3D bioprinting and biomaterials science. Despite these
(m.redzheb@matrichem.com)
advances, standardized biofabrication protocols approved for clinical applications
Citation: Redzheb M, Sbirkov Y, remain elusive, underscoring the need for research into widely accessible, non-
Valev A, et al. Collagen bioinks
redefined: Optimizing ionic strength immunogenic, and biocompatible bioinks that support chondrogenesis. This study
and growth factor delivery for proposes a strategy to improve the gelation kinetics of collagen bioinks by fine-
cartilage tissue engineering. tuning their ionic strength and reports a highly efficient sequestration of TGF-β1
Int J Bioprint. 2024;10(6):4566.
doi: 10.36922/ijb.4566 within them, alongside their compatibility with bioprinting live chondrocytes and
adipose-derived stem cells for cartilage tissue engineering. By adjusting sodium
Received: August 18, 2024 chloride and phosphate-buffered saline (PBS) concentrations, we demonstrate that
Revised: September 15, 2024
Accepted: September 29, 2024 reduced ionic strengths accelerate gelation, facilitating high-fidelity bioprinting
Published Online: September 29, while supporting high cell viability and proliferation. Furthermore, at 1% collagen
2024
concentration, the hydrogel effectively immobilized TGF-β1, with less than 0.5%
Copyright: © 2024 Author(s). released over two weeks, indicating potent sequestration capability. Using adipose-
This is an Open Access article derived mesenchymal stromal cells, histomorphological and transcriptomic analyses
distributed under the terms of the
Creative Commons Attribution reveal that the presence of TGF-β1 significantly enhances chondrogenesis. These
License, permitting distribution, results underscore the neglected role of ionic strength in optimizing collagen ink
and reproduction in any medium, properties for advanced bioprinting applications and highlight the potential of
provided the original work is
properly cited. collagen hydrogels as effective carriers for sustained growth factor delivery, paving
the way for successful cartilage tissue engineering strategies.
Publisher’s Note: AccScience
Publishing remains neutral with
regard to jurisdictional claims in
published maps and institutional Keywords: Collagen; Bioink; Bioprinting; Cartilage; Chondrocytes;
affiliations. Gelation kinetics; TGF-β1

Volume 10 Issue 6 (2024) 496 doi: 10.36922/ijb.4566