3D culture of multipotent cells derived from waste human ovarian follicular liquid and seeded onto gelatin cryogel

Current tissue engineering uses 3D biomaterials in combination with stem cells, since mature cells are often not available in sufficient amounts or quality. Biomaterial scaffolds have been widely used in reconstructive bone surgery not only as cell carriers providing mechanical support, but also as promoters of cell attachment and proliferation (1). In particular, gelatine cryogel scaffolds are promising new biomaterials owing to their biocompatibility and to substain the differentiation of mesenchymal stromal stem cells (MSCs) (2). Human MSC proliferate onto the surfaces with fibroblastic morphology and can differentiate into osteoblasts, chondrocytes and adipocytes (3). These cells can be isolated from several sources, including bone marrow and adipose tissue (4). Our previously studies showed the possibility to obtain MSCs also from the human ovarian follicular liquid (FL) that is usually wasted during in vitro fertilization (5). In this study, we tested the ability of these FL cells to grow and differentiate on gelatine cryogel in comparison with MSCs derived from human bone marrow. Samples and controls were analyzed with confocal and scanning electron microscopes. Results demonstrated that FL cells could grow on the biomaterial not only on the top but also in the layers below till 60mm of deepness. Data suggested that the observed cells are mesenchymal since positive for vimentin and CD44 (a typical MSC marker). Preliminary results showed also the capability of induced FL cells to osteogenic differentiation to produce bone extracellular matrix, expressing some specific proteins (i.e.osteopontin). In conclusion, MSCs derived from waste human ovarian follicular liquid showed promising affinity with 3D gelatine cryogel, opening new potential developments in biotech and medical applications

short term evaluation of the effects of orthodontic clear aligners on sleep bruxism activity

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Cell-Cycle Inhibition by Helicobacter pylori L-Asparaginase

Helicobacter pylori (H. pylori) is a major human pathogen causing chronic gastritis, peptic ulcer, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. One of the mechanisms whereby it induces damage depends on its interference with proliferation of host tissues. We here describe the discovery of a novel bacterial factor able to inhibit the cell-cycle of exposed cells, both of gastric and non-gastric origin. An integrated approach was adopted to isolate and characterise the molecule from the bacterial culture filtrate produced in a protein-free medium: size-exclusion chromatography, non-reducing gel electrophoresis, mass spectrometry, mutant analysis, recombinant protein expression and enzymatic assays. L-asparaginase was identified as the factor responsible for cell-cycle inhibition of fibroblasts and gastric cell lines. Its effect on cell-cycle was confirmed by inhibitors, a knockout strain and the action of recombinant L-asparaginase on cell lines. Interference with cell-cycle in vitro depended on cell genotype and was related to the expression levels of the concurrent enzyme asparagine synthetase. Bacterial subcellular distribution of L-asparaginase was also analysed along with its immunogenicity. H. pylori L-asparaginase is a novel antigen that functions as a cell-cycle inhibitor of fibroblasts and gastric cell lines. We give evidence supporting a role in the pathogenesis of H. pylori-related diseases and discuss its potential diagnostic application