Methacrylated gellan gum hydrogels for application in nucleus pulposus regeneration : in vitro and in vivo studies

Natural-based hydrogels have been attracting great deal of attention for tissue engineering of nucleus pulposus (NP). Gellan gum is an extracellular microbial polysaccharide from Sphingomonas elodea that forms a firm and transparent gel with interesting features for use as an in vitro 3D cell support, or as an in vivo injectable system. Recently, gellan gum-based hydrogels (ionic- and photocrosslinked methacrylated gellan gum) have been proposed as potential candidates for NP regeneration1. An important feature of these hydrogels will be their capacity to control blood vessel growth, since the NP is naturally avascular. Our aim was to investigate the biological performance of the developed hydrogels, in vitro. The angiogenic/anti-angiogenic potential of the GG-based hydrogels was also carried out in vivo, using an optimized adaptation of the chorioallantoic membrane (CAM) assay.