title: 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 factor-α, interferon-γ, transforming growth factor-β1, 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.
authors.affiliation: Adult Stem Cell Group, Institute of Biosciences and Medical Technology (BioMediTech), and School of Health Sciences, University of Tampere, Tampere, Finland; Science Center, Tampere University Hospital, Tampere, Finland mimmi.patrikoski@uta.fi.
authors.forename: Mimmi
authors.initials: M
authors.lastname: Patrikoski
authors.affiliation: Adult Stem Cell Group, Institute of Biosciences and Medical Technology (BioMediTech), and School of Health Sciences, University of Tampere, Tampere, Finland; Science Center, Tampere University Hospital, Tampere, Finland.
authors.forename: Jyrki
authors.initials: J
authors.lastname: Sivula
authors.affiliation: Adult Stem Cell Group, Institute of Biosciences and Medical Technology (BioMediTech), and School of Health Sciences, University of Tampere, Tampere, Finland; Science Center, Tampere University Hospital, Tampere, Finland.
authors.forename: Heini
authors.initials: H
authors.lastname: Huhtala
authors.affiliation: Adult Stem Cell Group, Institute of Biosciences and Medical Technology (BioMediTech), and School of Health Sciences, University of Tampere, Tampere, Finland; Science Center, Tampere University Hospital, Tampere, Finland.
authors.forename: Mika
authors.initials: M
authors.lastname: Helminen
authors.affiliation: Adult Stem Cell Group, Institute of Biosciences and Medical Technology (BioMediTech), and School of Health Sciences, University of Tampere, Tampere, Finland; Science Center, Tampere University Hospital, Tampere, Finland.
authors.forename: Fanny
authors.initials: F
authors.lastname: Salo
authors.affiliation: Adult Stem Cell Group, Institute of Biosciences and Medical Technology (BioMediTech), and School of Health Sciences, University of Tampere, Tampere, Finland; Science Center, Tampere University Hospital, Tampere, Finland.
authors.forename: Bettina
authors.initials: B
authors.lastname: Mannerström
authors.affiliation: Adult Stem Cell Group, Institute of Biosciences and Medical Technology (BioMediTech), and School of Health Sciences, University of Tampere, Tampere, Finland; Science Center, Tampere University Hospital, Tampere, Finland.
authors.forename: Susanna
authors.initials: S
authors.lastname: Miettinen
mesh_terms: D017667:Adipocytes / Q000166:cytology* / Q000276:immunology*; D000328:Adult; D018929:Cell Culture Techniques / Q000379:methods*; D002478:Cells, Cultured; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007959:Lymphocyte Culture Test, Mixed; D013234:Stem Cells / Q000166:cytology* / Q000276:immunology*
keywords: Adipose stem cells; Cellular therapy; Cytokines; Immunogenicity; Immunosuppression; Serum-free