title: Phenotypic and immunomodulatory properties of equine cord blood-derived mesenchymal stromal cells.
abstract: Multipotent mesenchymal stromal cells (MSC) have attracted interest for their cytotherapeutic potential, partly due to their immunomodulatory abilities. The aim of this study was to test the robustness of our equine cord blood (CB) MSC isolation protocol, to characterize the CB-MSC before and after cryopreservation, and to evaluate their immunosuppressive phenotype. We hypothesized that MSC can be consistently isolated from equine CB, have unique and reproducible marker expression and in vitro suppress lymphoproliferation. Preliminary investigation of constitutive cytoplasmic Toll-like receptor (TLR) 3 and 4 expression was also preformed due to their possible association with anti- or pro-inflammatory MSC phenotypes, respectively. Surface markers were assessed for antigen and mRNA expression by flow cytometry and quantitative polymerase chain reaction (qPCR). Immunomodulatory properties were evaluated in mixed lymphocyte reaction assays, and TLR3 and TLR4 expression were measured by qPCR and immunocytochemistry (ICC). CB-MSC were isolated from each off nine cord blood samples. CB-MSC highly expressed CD29, CD44, CD90, and lacked or had low expression of major histocompatibility complex (MHC) class I, MHC-II, CD4, CD8, CD11a/18 and CD73 before and after cryopreservation. CB-MSC suppressed in vitro lymphoproliferation and constitutively expressed TLR4. Our findings confirmed CB as a reliable MSC source, provides an association of surface marker phenotype and mRNA expression and suggest anti-inflammatory properties of CB-MSC. The relationship between TLRs and lymphocyte function warrants further investigation.
authors.affiliation: Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Canada.
authors.forename: Laurence
authors.initials: L
authors.lastname: Tessier
authors.affiliation: Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada.
authors.forename: Dorothee
authors.initials: D
authors.lastname: Bienzle
authors.affiliation: Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, Canada.
authors.forename: Lynn B
authors.initials: LB
authors.lastname: Williams
authors.affiliation: Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Canada; The Orthopaedic Research Lab, Aarhus University, Aarhus, Denmark.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Koch
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D015415:Biomarkers / Q000097:blood; D049109:Cell Proliferation; D002469:Cell Separation; D015925:Cryopreservation; D005312:Fetal Blood / Q000166:cytology*; D005786:Gene Expression Regulation; D006736:Horses; D006801:Humans; D056747:Immunomodulation; D007962:Leukocytes / Q000166:cytology; D008214:Lymphocytes / Q000166:cytology; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000276:immunology*; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051196:Toll-Like Receptor 3 / Q000235:genetics; D051197:Toll-Like Receptor 4 / Q000235:genetics
chemical_list: D015703:Antigens, CD; D015415:Biomarkers; D012333:RNA, Messenger; D051196:Toll-Like Receptor 3; D051197:Toll-Like Receptor 4