Controlling the rheology of gellan gum hydrogels in cell culture conditions

Successful culturing of tissues within polysaccharide hydrogels is reliant upon specific mechanical properties. Namely, the stiffness and elasticity of the gel have been shown to have a profound effect on cell behaviour in 3D cell cultures and correctly tuning these mechanical properties is critical to the success of culture. The usual way of tuning mechanical properties of a hydrogel to suit tissue engineering applications is to change the concentration of polymer or its cross-linking agents. In this study sonication applied at various amplitudes was used to control mechanical properties of gellan gum solutions and gels. This method enables the stiffness and elasticity of gellan gum hydrogels cross-linked with DMEM to be controlled without changing either polymer concentration or cross-linker concentration. Controlling the mechanical behaviour of gellan hydrogels impacted upon the activity of alkaline phosphatase (ALP) in encapsulated MC3T3 pre-osteoblasts. This shows the potential of applying a simple technique to generate hydrogels where tissue-specific mechanical properties can be produced that subsequently influence cell behaviour

Tissue engineering with gellan gum

Engineering complex tissues for research and clinical applications relies on high-performance biomaterials that are amenable to biofabrication, maintain mechanical integrity, support specific cell behaviours, and, ultimately, biodegrade. In most cases, complex tissues will need to be fabricated from not one, but many biomaterials, which collectively fulfill these demanding requirements. Gellan gum is an anionic polysaccharide with potential to fill several key roles in engineered tissues, particularly after modification and blending. This review focuses on the present state of research into gellan gum, from its origins, purification and modification, through processing and biofabrication options, to its performance as a cell scaffold for both soft tissue and load bearing applications. Overall, we find gellan gum to be a highly versatile backbone material for tissue engineering research, upon which a broad array of form and functionality can be built

Promising biomolecules

The osteochondral defect (OD) comprises the articular cartilage and its subchondral bone. The treatment of these lesions remains as one of the most problematic clinical issues, since these defects include different tissues, requiring distinct healing approaches. Among the growing applications of regenerative medicine, clinical articular cartilage repair has been used for two decades, and it is an effective example of translational medicine; one of the most used cell-based repair strategies includes implantation of autologous cells in degradable scaffolds such as alginate, agarose, collagen, chitosan, chondroitin sulfate, cellulose, silk fibroin, hyaluronic acid, and gelatin, among others. Concerning the repair of osteochondral defects, tissue engineering and regenerative medicine started to design single- or bi-phased scaffold constructs, often containing hydroxyapatite-collagen composites, usually used as a bone substitute. Biomolecules such as natural and synthetic have been explored to recreate the cartilage-bone interface through multilayered biomimetic scaffolds. In this chapter, a succinct description about the most relevant natural and synthetic biomolecules used on cartilage and bone repair, describing the procedures to obtain these biomolecules, their chemical structure, common modifications to improve its characteristics, and also their application in the biomedical fields, is given.(undefined)info:eu-repo/semantics/publishedVersio