BioProject

Mesenchymal stem/stromal cells (MSCs) with immunosuppressive properties are increasingly used in advanced cellular therapies. More...

Mesenchymal stem/stromal cells (MSCs) with immunosuppressive properties are increasingly used in advanced cellular therapies. Since the clinical use of hMSCs demands sequential cell expansions, we studied the effect of cell doublings on the phospholipid profile as well as functionality of human bone marrow mesenchymal stem cells (hBMSCs). In addition to the structural role of phospholipids in cell membranes, they provide precursors for eicosanoids and other signalling lipids modulating cellular functions. The hBMSCs, harvested from young adult and old donors (n=5 for both), showed clear compositional changes during cultivation, seen at the level of lipid classes, lipid species and acyl chains. As the main finding at the lipid class level, the ratio of phosphatidylinositol to phosphatidylserine was increased towards the late passage samples. In the species profiles, arachidonic acid (AA) containing species of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) clearly accumulated, while the species containing monounsaturated fatty acids decreased. This was related with an increase of AA, a major n-6 polyunsaturated fatty acid (n-6PUFA), in the total fatty acid pool of the cells, which happened at the expense of n-3PUFAs, especially docosahexenoic acid (DHA). Using hBMSCs from four of the young adult donors and four of the old donors, we found that gene expression of several enzymes involved in fatty acid metabolism (such as FADS1, FADS2 and SCD) was altered. The expression of genes related to the regulation of cell cycle, senescence and immunomodulation were altered. Our findings suggest that multistep expansion of hBMSCs alters their fatty acid metabolism and membrane phospholipid composition, which affects lipid signalling and eventually the immune function of the cells. Overall design: Cultured undifferentiated bone marrow-derived MSCs from old and young donors. Biological replicates: 4 old donors and 4 young donors, passages 4 and 8 from each. Less...