A thermosensitive low molecular weight hydrogel as scaffold for tissue engineering

Abstract

Hydrogels that are non-toxic, easy to use, cytocompatible, injectable and degradable are valuable biomaterials for tissue engineering and tissue repair. However, few compounds currently fulfi l these requirements. In this study, we describe the biological properties of a new type of thermosensitive hydrogel based on low-molecular weight glycosyl-nucleosyl-fl uorinated (GNF) compound. This gel forms within 25 min by self-assembly of monomers as temperature decreases. It degrades slowly in vitro and in vivo. It induces moderate chronic infl ammation and is progressively invaded by host cells and vessels, suggesting good integration to the host environment. Although human adult mesenchymal stem cells derived from adipose tissue (ASC) cannot adhere on the gel surface or within a 3D gel scaffold, cell aggregates grow and differentiate normally when entrapped in the GNF-based gel. Moreover, this hydrogel stimulates osteoblast differentiation of ASC in the absence of osteogenic factors. When implanted in mice, gel-entrapped cell aggregates survive for several weeks in contrast with gel-free spheroids. They are maintained in their original site of implantation where they interact with the host tissue and adhere on the extracellular matrix. They can differentiate in situ into alkaline phosphatase positive osteoblasts, which deposit a calcium phosphate-rich matrix. When injected into subcutaneous sites, gel-encapsulated cells show similar biological properties as implanted gel-cells complexes. These data point GNF-based gels as a novel class of hydrogels with original properties, in particular osteogenic potential, susceptible of providing new therapeutic solutions especially for bone tissue engineering applications.

3D anatomical and perfusion MRI for longitudinal evaluation of biomaterials for bone regeneration of femoral bone defect in rats

“…Indeed, hydrogels 31 or chitosan-based hydrogels 32 has already been detected as hyper-intense signals on MR images. Consequently, it is expected that the same anatomical and perfusion images can be performed on these materials.…”

Patterning of Endothelial Cells and Mesenchymal Stem Cells by Laser-Assisted Bioprinting to Study Cell Migration

“…Cells were expanded in Iscove's Modified Dulbecco's Medium (IMDM; Gibco, Thermo Fisher Scientific) containing 20% FBS, 12  μ g/mL endothelial cell growth supplement, and 90  μ g/mL heparin (ECGS/H 0.4% (v/v); PromoCell, Heidelberg, Germany) in gelatin-coated (0.2%; Sigma-Aldrich, Saint Quentin Fallavier, France) cell-culture flasks. Passage-1 cells were transduced with a lentiviral vector codding for the tdTomato fluorescent protein [18, 19]. Transduced and untransduced cells were used as stated for each experiment.…”

Controlled release of simvastatin‐loaded thermo‐sensitive PLGA‐PEG‐PLGA hydrogel for bone tissue regeneration: in vitro and in vivo characteristics

“…However, injectable hydrogel polymers have been applied more routinely due to their simpler invasive procedures, their site‐specific administration and their convenient formability under mild conditions . In particular, thermo‐sensitive hydrogels are safe and convenient for phase transitions and can change between a liquid state and a solid state based on the ambient temperature . Thermo‐sensitive hydrogels are capable of being injected directly into the defect cavity in the impaired tissue at a low temperature and solidify at body temperature, avoiding any use of physical or chemical initiators …”