Growth Factors Cross-Linked to Collagen Microcarriers Promote Expansion and Chondrogenic Differentiation of Human Mesenchymal Stem Cells

Abstract

Tissue engineering is a field in progressive expansion and requires constant updates in methods and devices. One of the central fields is the development of biocompatible, biodegradable, and injectable scaffolds, such as collagen microcarriers. To enhance cell attachment and produce a cost-effective cell culture solution with local stimulation of cells, basic fibroblast growth factor (bFGF) or transforming growth factor-β1 (TGF-β1) was covalently immobilized on microcarriers either by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) or riboflavin/UV (RB/UV) light-mediated cross-linking. Collagen microcarriers cross-linked with bFGF or TGF-β1 were used for expansion and chondrogenic differentiation of human mesenchymal stem cells (MSCs). Evaluation methods included cell viability test, chondrogenic marker expression (aggrecan and collagen type I and type II), histological detection of proteoglycans, and immunohistochemical analysis. Cross-linking strengthened the collagen structure of the microcarriers and reduced collagenase-mediated degradation. MSCs effectively proliferated on microcarriers cross-linked with bFGF, especially by EDC/NHS cross-linking. Chondrogenic differentiation of MSCs was induced by TGF-β1 cross-linked on microcarriers, promoting gene expression and protein accumulation of aggrecan and collagen type I and type II, as well as proteoglycans. Cross-linking by RB/UV enhanced chondrogenesis more than any other group. In addition, cross-linking reduced scaffold shrinkage exerted by MSCs during chondrogenesis, a desirable feature for microcarriers if used as tissue defect filler. In conclusion, cross-linking of bFGF or TGF-β1 to collagen microcarriers supported in vitro proliferation and chondrogenesis, respectively. If translated in vivo and in clinical practice, such approach might lead a step closer to development of a cost-effective and locally acting device for cell-based therapy.

Interaction between Mesenchymal Stem Cells and Intervertebral Disc Microenvironment: From Cell Therapy to Tissue Engineering

“…For example, the combination of TGF-β with a MSC-embedded polymerized fibrin scaffold implanted in a rat model demonstrated to inhibit MSC apoptosis and led to an increased disc height when compared to the scaffold alone [16]. Similarly, in another study, BM-MSCs were cultured with collagen microcarriers functionalized with either TGF-β or bFGF; while the former was significantly upregulated MSC chondrogenic differentiation and production of aggrecan, collagen, and proteoglycan, bFGF notably increased cell proliferation [140].…”

Macromolecule Biomaterials Promote the Osteogenic Differentiation Capacity of Equine Adipose -Derived Mesenchymal Stem Cells

“…The combined silica and collagen provides inorganic/organic composite with promising characteristics regarding chemical, structural and technological parameters for the biomaterial suitable for bone engineering [13,21,22]. Currently, a group of evidence have shown the effectiveness of collagen based microcarrier scaffold for MSCs proliferation and chondrogenic differentiation [23]. Similar study has combined MC with chitosan hydrogel revealed an enhanced metabolic activity and surface adhesion of chondrocytes suggesting the usefulness of the composite for tissue regeneration [24].…”

The Good the Bad and the Ugly of Glycosaminoglycans in Tissue Engineering Applications

“…Natural polymers have the obvious advantage of biological recognition, providing the cells with ECM molecules that can positively support cell function and adhesion [363,364,365,366]. Collagen, being a major component of the cartilage ECM, is a widely used natural polymer in cartilage TE, and is the most common scaffold to be incorporated into MACI procedures [55,60,367,368].…”