Adhesion, proliferation and osteogenic differentiation of human MSCs cultured under perfusion with a marine oxygen carrier on an allogenic bone substitute.

Tissue engineering strategies have been developed to optimize osseointegration in dental implant surgery. One of the major problems is the non-homogeneous spatial cell distribution in the scaffold, as well as subsequent matrix production. Insufficient nutrient and oxygen supplies inside the scaffold are factors in this phenomenon. To mediate this gradient formation, we have implemented a perfusion culture method to seed human bone marrow mesenchymal stem cells (MSCs) into three-dimensional (3-D)-allogenic bone scaffolds in combination with a marine haemoglobin, HEMOXCell®, for oxygen delivery. Cell culture was performed under static and perfusion conditions, with standard and osteogenic media, with and without HEMOXCell®. The cell seeding efficiency, as well as MSC/scaffold cytocompatibly were assessed using viability and proliferation assays. Scaffolds' cellularization and extracellular matrix (ECM) formation were analyzed using scanning electron microscopy and histological staining. Cell differentiation was investigated with osteogenic biomarkers gene expression analysis. The perfusion culture was observed to significantly promote MSC proliferation and differentiation throughout the scaffolds, especially when using the induction medium w/HEMOXCell®. Our data suggest that perfusion culture of MSC into allogenic bone substitute with HEMOXCell® as a natural oxygen carrier is promising for tissue engineering applications to oxygenate hypoxic areas and to promote cellular proliferation.

MicroRNA-based diagnostic tools for advanced fibrosis and cirrhosis in patients with chronic hepatitis B and C.

Staging fibrosis is crucial for the prognosis and to determine the rapid need of treatment in patients with chronic hepatitis B (CHB) and C (CHC). The expression of 13 fibrosis-related microRNAs (miRNAs) (miR-20a, miR-21, miR-27a, miR-27b, miR-29a, miR-29c, miR-92a, miR-122, miR-146a, miR-155, miR-221, miR-222, and miR-224) was analyzed in 194 serums and 177 liver biopsies of patients with either CHB or CHC to develop models to diagnose advanced fibrosis and cirrhosis (Metavir F3-F4). In CHB patients, the model (serum miR-122, serum miR-222, platelet count and alkaline phosphatase) was more accurate than APRI and FIB-4 to discriminate in between mild and moderate fibrosis (F1-F2) and F3-F4 (AUC of CHB model: 0.85 vs APRI: 0.70 and FIB-4: 0.81). In CHC patients, the model (hepatic miR-122, hepatic miR-224, platelet count, albumin and alanine aminotransferase) was more accurate than both APRI and FIB-4 to discriminate in between patients with F3-F4 and F1-F2 (AUC of the CHC model = 0.93 vs APRI: 0.86 and FIB-4: 0.79). Most of the miRNAs tested were differentially expressed in patients with CHB and CHC. In particular, serum miR-122 was 28-fold higher in patients with CHB than in those with CHC. Both CHB and CHC models may help for the diagnosis of advanced fibrosis and cirrhosis (F3-F4).