title: Ultrastructural study of cultured ovine bone marrow-derived mesenchymal stromal cells.
abstract: Ovine bone marrow-derived mesenchymal stromal cells (oBM-MSCs) represent a good animal model for cell-based therapy and tissue engineering. Despite their use as a new therapeutic tool for several clinical applications, the morphological features of oBM-MSCs are yet unknown. Therefore, in this study the ultrastructural phenotype of these cells was analysed by transmission electron microscopy (TEM). The oBM-MSCs were isolated from the iliac crest and cultured until they reached near-confluence. After trypsinization, they were processed to investigate their ultrastructural features as well as specific surface marker proteins by flow cytometry and immunogold electron microscopy. Flow cytometry displayed that all oBM-MSCs lacked expression of CD31, CD34, CD45, HLA-DR whereas they expressed CD44, CD58, HLAI and a minor subset of the cell population (12%) exhibited CD90. TEM revealed the presence of two morphologically distinct cell types: cuboidal electron-lucent cells and spindle-shaped electron-dense cells, both expressing the CD90 antigen. Most of the electron-lucent cells showed glycogen aggregates, dilated cisternae of RER, moderately developed Golgi complex, and secretory activity. The electron-dense cell type was constituted by two different cell-populations: type A cells with numerous endosomes, dense bodies, rod-shaped mitochondria and filopodia; type B cells with elongated mitochondria, thin pseudopodia and cytoplasmic connectivity with electron-lucent cells. These morphological findings could provide a useful support to identify "in situ" the cellular components involved in the cell-therapy when cultured oBM-MSCs are injected.
authors.affiliation: Department of Emergency and Organ transplantation, University of Bari "Aldo Moro", Italy. Electronic address: salvatore.desantis@uniba.it.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Desantis
authors.affiliation: Department of Emergency and Organ transplantation, University of Bari "Aldo Moro", Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Accogli
authors.affiliation: Department of Emergency and Organ transplantation, University of Bari "Aldo Moro", Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Zizza
authors.affiliation: Department of Biology, University of Bari "Aldo Moro", Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Mastrodonato
authors.affiliation: Medestea Research and Production Laboratories, Consorzio CARSO, Bari, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Blasi
authors.affiliation: Department of Emergency and Organ transplantation, University of Bari "Aldo Moro", Italy.
authors.forename: Edda
authors.initials: E
authors.lastname: Francioso
authors.affiliation: Department of Emergency and Organ transplantation, University of Bari "Aldo Moro", Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Rossi
authors.affiliation: Department of Emergency and Organ transplantation, University of Bari "Aldo Moro", Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Crovace
authors.affiliation: Department of Emergency and Organ transplantation, University of Bari "Aldo Moro", Italy.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Resta
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000737:chemistry; D001854:Bone Marrow Cells / Q000648:ultrastructure*; D002478:Cells, Cultured; D003593:Cytoplasm / Q000648:ultrastructure; D011992:Endosomes / Q000648:ultrastructure; D005434:Flow Cytometry; D006003:Glycogen / Q000378:metabolism; D006056:Golgi Apparatus / Q000648:ultrastructure; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism; D059630:Mesenchymal Stem Cells / Q000648:ultrastructure*; D046529:Microscopy, Electron, Transmission; D008928:Mitochondria / Q000648:ultrastructure; D012756:Sheep; D014357:Trypsin / Q000737:chemistry
chemical_list: D015703:Antigens, CD; D008565:Membrane Proteins; D006003:Glycogen; D014357:Trypsin
keywords: Bone marrow; Flow cytometry; MSCs; Ovine; Transmission electron microscopy