Identification of molecular pathways and protein-protein interactions in adipose tissue-derived mesenchymal stromal cells (ASCs) under physiological oxygen concentration in a diabetic rat model.

Objectives: Adipose tissue-derived mesenchymal stromal cells (ASCs) are useful in cell-based therapy. However, it is well known that diabetes mellitus (DM) alters ASCs' functionality. The majority of in vitro studies related to ASCs are developed under non-physiological oxygen conditions. Therefore, they may not reflect the full effects of DM on ASCs, in vivo. The main aim of the current study is to identify molecular pathways and underlying biological mechanisms affected by diabetes on ASCs in physiological oxygen conditions. Materials and Methods: ASCs derived from healthy (ASCs-C) and diabetic (ASCs-D) rats were expanded under standard culture conditions (21% O2) or cultured in physiological oxygen conditions (3% O2) and characterized. Differential gene expressions (DEGs) of ASCs-D with respect to ASCs-C were identified and analyzed with bioinformatic tools. Protein-protein interaction (PPI) networks, from up- and down-regulated DEGs, were also constructed. Results: The bioinformatic analysis revealed 1354 up-regulated and 859 down-regulated DEGs in ASCs-D, with 21 and 78 terms over and under-represented, respectively. Terms linked with glycosylation and ribosomes were over-represented and terms related to the activity of RNA-polymerase II and transcription regulation were under-represented. PPI network disclosed RPL11-RPS5 and KDR-VEGFA as the main interactions from up- and down-regulated DEGs, respectively. Conclusion: These results provide valuable information about gene pathways and underlying molecular mechanisms by which diabetes disturbs ASCs biology in physiological oxygen conditions. Furthermore, they reveal, molecular targets to improve the use of ASCs in autologous transplantation.

Evaluation of hepatitis C viral RNA persistence in HIV-infected patients with long-term sustained virological response by droplet digital PCR.

Several studies have reported the persistence of HCV RNA in liver and/or peripheral blood mononuclear cells (PBMCs) in spite of undetectable viremia in patients who have achieved sustained virological response (SVR). This event, defined as occult HCV infection, remains controversial and low titers of persistent virus may be underestimated because it has not yet been analyzed by a highly sensitive test such as droplet digital PCR (ddPCR). This method provides an alternate ultra-sensitive detection technique for very low numbers of copies of viral RNA or DNA. The aim of this study was to evaluate the persistence of HCV in HIV-coinfected patients with long-term SVR using ddPCR. For each patient, the presence of HCV RNA in serum and PBMCs at baseline was determined by nested RT-ddPCR. Patients with HCV RNA in PBMCs at baseline were followed until the end of the study. One hundred and twenty-three patients were analyzed for persistence of HCV RNA in serum and PBMCs. Persistence of HCV was not found in serum in any patient. HCV RNA was detected in PBMCs in one patient (0.81%; 95% CI: 0.04-3.94) and resolved spontaneously during follow-up. Persistence of HCV RNA in PBMCs is not a common event in HIV/HCV co-infected patients with long-term SVR evaluated by RT-ddPCR.