A new composite hydrogel combining the biological properties of collagen with the mechanical properties of a supramolecular scaffold for bone tissue engineering

Abstract

Tissue engineering is a promising alternative to autografts, allografts, or biomaterials to address the treatment of severe and large bone lesions. Classically, tissue engineering products associate a scaffold and cells and are implanted or injected into the lesion. These cells must be embedded in an appropriate biocompatible scaffold, which offers a favourable environment for their survival and differentiation. Here, we designed a composite hydrogel composed of collagen I, an extracellular matrix protein widely used in several therapeutic applications, which we associated with a physical hydrogel generated from a synthetic small amphiphilic molecule. This composite showed improved mechanical and biological characteristics as compared with gels obtained from each separate compound. Incorporation of the physical hydrogel prevented shrinkage of collagen and cell diffusion out of the gel and yielded a gel with a higher elastic modulus than those of gels obtained with each component alone. The composite hydrogel allowed cell adhesion and proliferation in vitro and long-term cell survival in vivo. Moreover, it promoted the differentiation of human adipose-derived stem cells in the absence of any osteogenic factors. In vivo, cells embedded in the composite gel and injected subcutaneously in immunodeficient mice produced lamellar osteoid tissue and differentiated into osteoblasts. This study points this new composite hydrogel as a promising scaffold for bone tissue engineering applications.

Alginate-nanohydroxyapatite hydrogel system: Optimizing the formulation for enhanced bone regeneration

“…Materials like auto−/allografts, inert metallic and ceramic implants have been used to fill, replace, repair or regenerate injured or diseased bone with clinical success [1][2][3]. However, these applications have shown some associated limitations such as the risk of long-term foreign body reaction, pathogen transmission, immunogenic rejection, impaired bone formation, poor vascularization and integration, and inaccurate fitting to the defect size and shape [2][3][4][5].…”

Commercially Relevant Orthogonal Multi‐Component Supramolecular Hydrogels for Programmed Cell Growth

“…Moving away from amides, Barthélémy and co‐workers elegantly applied nucleobase‐derived gels with human mesenchymal stem cells—cell survival was dependent on gelator structure . This gelator was used in combination with collagen to create hybrid materials . Others have also made use of guanosine‐derived gels for cell culture .…”

“…Surprisingly, given their biological importance, there are very few examples of sugar‐based LMWGs being used for tissue culture. There are limited examples of peptides modified with sugars, and Barthélémy's nucleobase gelators contain sugar units, but other sugar‐containing gelators applied in tissue engineering remain very rare…”

“…[12] This gelator was used in combination with collagen to create hybrid materials. [13] Others have also made use of guanosine-derived gels for cell culture. [14] Surprisingly,g iven their biological importance,t here are very few exampleso fs ugar-basedL MWGs being used for tissue culture.…”

“…[14] Surprisingly,g iven their biological importance,t here are very few exampleso fs ugar-basedL MWGs being used for tissue culture. Therea re limited examples of peptides modified with sugars, [15] and BarthØlØmy's nucleobase gelators contain sugar units, [12,13] buto ther sugar-containing gelators appliedint issue engineeringr emainvery rare. [16] In this work, we wanted to demonstrate ac ommercially viablea pproach to simple self-assembled tissue culture materials.…”