Restored in vivo-like membrane lipidomics positively influence in vitro features of cultured mesenchymal stromal/stem cells derived from human placenta

BACKGROUND: The study of lipid metabolism in stem cell physiology has recently raised great interest. The role of lipids goes beyond the mere structural involvement in assembling extra- and intra-cellular compartments. Nevertheless, we are still far from understanding the impact of membrane lipidomics in stemness maintenance and differentiation patterns. In the last years, it has been reported how in vitro cell culturing can modify membrane lipidomics. The aim of the present work was to study the membrane fatty acid profile of mesenchymal stromal cells (MSCs) derived from human fetal membranes (hFM-MSCs) and to correlate this to specific biological properties by using chemically defined tailored lipid supplements (Refeed®). METHODS: Freshly isolated hFM-MSCs were characterized for their membrane fatty acid composition. hFM-MSCs were cultivated in vitro following a classical protocol and their membrane fatty acid profile at different passages was compared to the profile in vivo. A tailored Refeed® lipid supplement was developed with the aim of reducing the differences created by the in vitro cultivation and was tested on cultured hFM-MSCs. Cell morphology, viability, proliferation, angiogenic differentiation, and immunomodulatory properties after in vitro exposure to the tailored Refeed® lipid supplement were investigated. RESULTS: A significant modification of hFM-MSC membrane fatty acid composition occurred during in vitro culture. Using a tailored lipid supplement, the fatty acid composition of cultured cells remained more similar to their in vivo counterparts, being characterized by a higher polyunsaturated and omega-6 fatty acid content. These changes in membrane composition had no effect on cell morphology and viability, but were linked with increased cell proliferation rate, angiogenic differentiation, and immunomodulatory properties. In particular, Refeed®-supplemented hFM-MSCs showed greater ability to express fully functional cell membrane molecules. CONCLUSIONS: Culturing hFM-MSCs alters their fatty acid composition. A tailored lipid supplement is able to improve in vitro hFM-MSC functional properties by recreating a membrane environment more similar to the physiological counterpart. This approach should be considered in cell therapy applications in order to maintain a higher cell quality during in vitro passaging and to influence the outcome of cell-based therapeutic approaches when cells are administered to patients

Influence of species and anatomical location on chondrocyte expansion

<p>Abstract</p> <p>Background</p> <p>Bovine articular cartilage is often used to study chondrocytes <it>in vitro</it>. It is difficult to correlate <it>in vitro </it>studies using bovine chondrocytes with <it>in vivo </it>studies using other species such as rabbits and sheep. The aim of this investigation was to study the effect of species, anatomical location and exogenous growth factors on chondrocyte proliferation <it>in vitro</it>.</p> <p>Methods</p> <p>Equine (EQ), bovine (BO) and ovine (OV) articular chondrocytes from metacarpophalangeal (fetlock (F)), shoulder (S) and knee (K) joints were cultured in tissue culture flasks. Growth factors (rh-FGFb: 10 ng/ml; rh-TGFβ: 5 ng/ml) were added to the cultures at days 2 and 4. On day 6, cells were counted and flow cytometry analysis was performed to determine cell size and granularity. A three factor ANOVA with paired Tukey's correction was used for statistical analysis.</p> <p>Results</p> <p>After 6 days in culture, cell numbers had increased in control groups of EQ-F, OV-S, OV-F and BO-F chondrocytes. The addition of rh-FGFb led to the highest increase in cell numbers in the BO-F, followed by EQ-F and OV-S chondrocytes. The addition of rh-TGFβ increased cell numbers in EQ-S and EQ-F chondrocytes, but showed nearly no effect on EQ-K, OV-K, OV-S, OV-F and BO-F chondrocytes. There was an overall difference with the addition of growth factors between the different species and joints.</p> <p>Conclusion</p> <p>Different proliferation profiles of chondrocytes from the various joints were found. Therefore, we recommend performing <it>in vitro </it>studies using the species and site where subsequent <it>in vivo </it>studies are planned.</p

Placenta-Derived Cells and Their Therapeutic Applications

The human placenta serves as a medium of exchange of oxygen, nutrients, and waste products between the mother and the fetus. This foetomaternal organ provides the most intimate connection between the fetal and maternal tissues. The placental tissues originate very early during embryogenesis, prior to gastrulation, suggesting that they may harbor cells that retain some stem/progenitor cell potential with the ability to differentiate toward different cell lineages. Furthermore, placenta plays an essential role in maintaining fetomaternal tolerance during pregnancy, indicating that placental cells may have special immunomodulatory properties and, finally, placenta can be easily procured after delivery and its use is free from ethical concern. An understanding of the structure of the placenta, described in detail later, will be of help in the identification of the varied cell types that can be isolated from its specific regions

Placental Stem/Progenitor Cells: Isolation and Characterization

Mounting evidence suggests that the human term placenta could be a source of stem/progenitor cells with therapeutic potential and wide applicability for regenerative/reparative medicine approaches. Over recent years, we have learned that different cell types can be isolated from various regions of the human placenta. This chapter aims to discuss recent signifi cant developments regarding the isolation of these cells and to present what is to date known in terms of their phenotype, differentiation potential, and immunological properties. We will begin with a brief description of the structure of the placenta in order to provide readers with a clear picture of the target regions for stem/progenitor cell isolation, and we will then discuss trends which are evident in the properties of these cells by drawing on different characterization studies which have been performed. Furthermore, we have highlighted that although significant progress has been made, further improvements are required both for the establishment, and in particular the standardization, of isolation protocols for placental cells, and also for characterization methods which would lead to a better understanding of the phenotype of these cells and of their potential in terms of cell differentiation, immunogenicity, and other properties which would be relevant to their clinical application