title: Characterization of mesenchymal stem cells derived from the equine synovial fluid and membrane.
abstract: BACKGROUND
  Isolation of mesenchymal stem cells (MSCs) in equines, has been reported for different tissues including bone marrow, adipose, umbilical cord, peripheral blood, and yolk sac. In regard to the MSCs derived from synovial fluid (SF) or membrane (SM), there is data available for humans, dogs, pigs, goats and horses. Especially in equines, these cells have being considered promising candidates for articular regeneration. Herein, we established and characterized MSCs obtained from equine SF and SM. Samples were obtained during arthroscopy and cultured using MEM (Minimum Essential Medium). MSCs were characterized by morphology and expression of specific markers for stem cells, pluripotency, inflammation, and cell cycle.
  
  
  RESULTS
  The medium MEM was more effective (97% ± 2) to maintain both cultures. The cultures were composed by adherent cells with fibroblast-like shape, which had a growth pattern represented by a sigmoidal curve. After the expansion, the cells were analyzed by flow cytometry for stem cells, inflammatory, and cell cycle markers, and both lineages showed significant expression of CD45, Oct3/4, Nanog, CD105, CD90, CD34, CD117, CD133, TRA-1-81, VEGF, and LY6a. In contrast, there were differences in the cell cycle phases between the lineages, which was not observed in relation to the mitochondrial electrical potential.
  
  
  CONCLUSIONS
  Given the large impact that joint pathology has on the athletic performance horses, our results suggested that the SF and SM are promising sources of stem cells with satisfactory characteristics of growth and gene expression that can be used in equine regenerative medicine.
authors.affiliation: Department of Surgery, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Av. Prof. Dr. Orlando Marques de Paiva, 87, Cidade Universitária, 05508-270, São Paulo, SP, Brazil. alineambrogifranco@usp.br.
authors.forename: Aline Ambrogi Franco
authors.initials: AA
authors.lastname: Prado
authors.affiliation: Department of Surgery, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Av. Prof. Dr. Orlando Marques de Paiva, 87, Cidade Universitária, 05508-270, São Paulo, SP, Brazil. phelipe.favaron@yahoo.com.br.
authors.forename: Phelipe Oliveira
authors.initials: PO
authors.lastname: Favaron
authors.affiliation: Department of Surgery, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Av. Prof. Dr. Orlando Marques de Paiva, 87, Cidade Universitária, 05508-270, São Paulo, SP, Brazil. silvalc@usp.br.
authors.forename: Luis Claudio Lopes Correia
authors.initials: LC
authors.lastname: da Silva
authors.affiliation: Department of Surgery, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Av. Prof. Dr. Orlando Marques de Paiva, 87, Cidade Universitária, 05508-270, São Paulo, SP, Brazil. baccarin@usp.br.
authors.forename: Raquel Yvonne Arantes
authors.initials: RY
authors.lastname: Baccarin
authors.affiliation: Department of Surgery, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Av. Prof. Dr. Orlando Marques de Paiva, 87, Cidade Universitária, 05508-270, São Paulo, SP, Brazil. miglino@usp.br.
authors.forename: Maria Angelica
authors.initials: MA
authors.lastname: Miglino
authors.affiliation: Laboratory of Biochemical and Biophisic, Butantan Institute, Av. Dr. Vital Brasil, 1500, 05503-900, Sao Paulo, Brazil. durvanei@usp.br.
authors.forename: Durvanei Augusto
authors.initials: DA
authors.lastname: Maria
mesh_terms: D000818:Animals; D002453:Cell Cycle; D049109:Cell Proliferation; D002478:Cells, Cultured; D006736:Horses; D053078:Membrane Potential, Mitochondrial; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology*; D013582:Synovial Fluid / Q000166:cytology*; D013583:Synovial Membrane / Q000166:cytology*