Different Culture Conditions Modulate the Immunological Properties of Adipose Stem Cells

Abstract

The potential of human adipose stem cells (ASCs) for regenerative medicine has received recognition owing to their ease of isolation and their multilineage differentiation capacity. Additionally, low immunogenicity and immunosuppressive properties make them a relevant cell source when considering immunomodulation therapies and allogeneic stem cell treatments. In the current study, immunogenicity and immunosuppression of ASCs were determined through mixed lymphocyte reactions. The immunogenic response was analyzed after cell isolation and expansion in fetal bovine serum (FBS), human serum (HS)-supplemented medium, and xeno-free and serum-free (XF/SF) conditions. Additionally, the immunophenotype and the secretion of CXC chemokine ligand 8 (CXCL8), CXCL9, CXCL10, C-C chemokine ligand 2 (CCL2), CCL5, interleukin 2 (IL-2), IL-4, IL-6, IL-10, IL-17A, tumor necrosis factora, interferon-g, transforming growth factor-b1, indoleamine 2,3-deoxygenase, Galectin-1, and Galectin-3 were analyzed. The results showed that ASCs were weakly immunogenic when expanded in any of the three conditions. The significantly strongest suppression was observed with cells expanded in FBS conditions, whereas higher ASC numbers were required to display suppression in HS or XF/SF conditions. In addition, statistically significant differences in protein secretion were observed between direct versus indirect cocultures and between different culture conditions. The characteristic immunophenotype of ASCs was maintained in all conditions. However, in XF/SF conditions, a significantly lower expression of CD54 (intercellular adhesion molecule 1) and a higher expression of CD45 (lymphocyte common antigen) was observed at a low passage number. Although culture conditions have an effect on the immunogenicity, immunosuppression, and protein secretion profile of ASCs, our findings demonstrated that ASCs have low immunogenicity and promising immunosuppressive potential whether cultured in FBS, HS, or XF/SF conditions. STEM CELLS TRANSLATIONAL

Platelet lysate obtained via plateletpheresis performed in standing and awake equine donors

“…However, there is growing interest in finding suitable alternatives to FBS, because it is an ill‐defined mixture of culture components and is ethically controversial in terms of the harvest and collection of FBS from bovine fetuses . In addition, it contains endotoxins (lipopolysaccharide) and xenogenic antigens, which may alter the characteristics of mesenchymal stem cells (MSCs) developed for cell tranplantation . Moreover, cells previously exposed to FBS may become carriers and serve as a potential route of transmission of animal pathogens .…”

Comparison of human platelet lysate alternatives using expired and freshly isolated platelet concentrates for adipose-derived stromal cell expansion

“…This can be achieved, in part, by changing to chemically defined, xeno-free or human bloodderived alternatives (4,6). These human blood-derived alternatives include human serum, platelet-rich plasma, platelet-poor plasma and platelet lysate (7)(8)(9)(10). Studies comparing these alternatives make use of guidelines set out by the International Society of Cellular Therapy (ISCT) and International Fat Applied Technology Society for the characterisation of ASCs (11,12).…”

The Impact of Cell-Expansion and Inflammation on The Immune-Biology of Human Adipose Tissue-Derived Mesenchymal Stromal Cells

“…On top of that, the lipoaspirate is considered to be medical waste, making adipose tissue an ideal source of MSCs [6,7,13]. Since the number of clinical applications using AT-MSCs is increasing, it is of main importance that the safety and full definition of this cell population is addressed [4,[33][34][35]. In vitro expansion is of relevance to allow suitable amount of AT-MSCs for transplantation.…”

“…In vitro expansion is of relevance to allow suitable amount of AT-MSCs for transplantation. It is clear from the literature that this in vitro expansion of MSCs can lead to distinct changes in MSCs phenotype [33], so defining expansion and environmental conditions, which are important for the biology of the cells, have to be considered when these cells are intended to be used for clinical scale-up [36].…”