Collagen type I hydrogel allows migration, proliferation, and osteogenic differentiation of rat bone marrow stromal cells

Abstract

Hydrogels are potentially useful for many purposes in regenerative medicine including drug and growth factor delivery, as single scaffold for bone repair or as a filler of pores of another biomaterial in which host mesenchymal progenitor cells can migrate in and differentiate into matrix-producing osteoblasts. Collagen type I is of special interest as it is a very important and abundant natural matrix component. The purpose of this study was to investigate whether rat bone marrow stromal cells (rBMSCs) are able to adhere to, to survive, to proliferate and to migrate in collagen type I hydrogels and whether they can adopt an osteoblastic fate. rBMSCs were obtained from rat femora and plated on collagen type I hydrogels. Prior to harvest by day 7, 14, and 21, hydrogels were fluorescently labeled, cryo-cut and analyzed by fluorescent-based and laser scanning confocal microscopy to determine cell proliferation, migration, and viability. Osteogenic differentiation was determined by alkaline phosphatase activity. Collagen type I hydrogels allowed the attachment of rBMSCs to the hydrogel, their proliferation, and migration towards the inner part of the gel. rBMSCs started to differentiate into osteoblasts as determined by an increase in alkaline phosphatase activity after two weeks in culture. This study therefore suggests that collagen type I hydrogels could be useful for musculoskeletal regenerative therapies.

Enhanced osteoblastogenesis in three-dimensional collagen gels

“…At earlier time points, at 2, 4 or 6 h after seeding, the levels of osteoblast gene expression were similar in cells growing in 2D and 3D collagen cultures (data not shown). In a number of previous studies, 3,8,14,15 collagen gels were formed first and osteoblasts were seeded on top of the gels, allowing for the analysis of cell migration into the gels. Interestingly, while osteoblasts migrated into the gels and formed a 3D cell network, fibroblasts seeded on top of the gels migrated through them and formed a monolayer on the plastic underneath.…”

“…It has been shown that culturing cells in 3D collagen gels affects cell shape, cell-cell interactions and response to soluble factors. 1,3 Collagen gels are also being considered in regenerative medicine of the musculoskeletal system as potential biomimetic bone replacement materials for use in cases of bone loss by trauma or disease. 4 Collagen I provides a tissue-derived natural polymer; it is biocompatible and biodegradable and its mechanical and biological properties can be controlled and varied as required.…”

“…4 Collagen I provides a tissue-derived natural polymer; it is biocompatible and biodegradable and its mechanical and biological properties can be controlled and varied as required. 3,5 As a scaffold for bone regeneration, collagen can be used alone or in combination with various natural polymers and minerals that provide better representation of the extracellular environment, including hyaluronic acid-modified chitosan/collagen/hydroxyapatite composites 6 and collagen/hydroxyapatite scaffolds. 4 Although a number of studies have investigated osteoblasts cultured in 3D collagen gels, they mostly used microscopy for visual analysis of the osteoblast phenotype and alkaline phosphatase activity as a measure of osteoblast function.…”

“…4 Although a number of studies have investigated osteoblasts cultured in 3D collagen gels, they mostly used microscopy for visual analysis of the osteoblast phenotype and alkaline phosphatase activity as a measure of osteoblast function. 1,3,[7][8][9] The aim of the current study was to directly compare osteoblasts growing in parallel in 3D collagen gels and in 2D on plastic and to comprehensively characterize the effects of these growth environments on the expression of osteoblast marker genes, on cell differentiation and on responses to factors that affect the rate of cell proliferation.…”

Hydrogels based on collagen and fibrin – frontiers and applications

“…Both proteins serve as a scaffold for tissue regeneration and can promote the migration and ingrowth of cells. Fibrin and collagen are an ideal biomaterial for hydrogel scaffolds, because of their distinguished biocompatibility and cell adhesion capability [9,10].…”