title: A2B5+/GFAP+ Cells of Rat Spinal Cord Share a Similar Lipid Profile with Progenitor Cells: A Comparative Lipidomic Study.
abstract: The central nervous system (CNS) harbors multiple glial fibrillary acidic protein (GFAP) expressing cell types. In addition to the most abundant cell type of the CNS, the astrocytes, various stem cells and progenitor cells also contain GFAP+ populations. Here, in order to distinguish between two types of GFAP expressing cells with or without the expression of the A2B5 antigens, we performed lipidomic analyses on A2B5+/GFAP+ and A2B5-/GFAP+ cells from rat spinal cord. First, A2B5+/GFAP- progenitors were exposed to the leukemia inhibitory factor (LIF) or bone morphogenetic protein (BMP) to induce their differentiation to A2B5+/GFAP+ cells or A2B5-/GFAP+ astrocytes, respectively. The cells were then analyzed for changes in their phospholipid, sphingolipid or acyl chain profiles by mass spectrometry and gas chromatography. Compared to A2B5+/GFAP- progenitors, A2B5-/GFAP+ astrocytes contained higher amounts of ether phospholipids (especially the species containing arachidonic acid) and sphingomyelin, which may indicate characteristics of cellular differentiation and inability for multipotency. In comparison, principal component analyses revealed that the lipid composition of A2B5+/GFAP+ cells retained many of the characteristics of A2B5+/GFAP- progenitors, but their lipid profile was different from that of A2B5-/GFAP+ astrocytes. Thus, our study demonstrated that two GFAP+ cell populations have distinct lipid profiles with the A2B5+/GFAP+ cells sharing a phospholipid profile with progenitors rather than astrocytes. The progenitor cells may require regulated low levels of lipids known to mediate signaling functions in differentiated cells, and the precursor lipid profiles may serve as one measure of the differentiation capacity of a cell population.
authors.affiliation: Department of Biosciences, University of Helsinki, Biocenter 3, P.O. Box 65, 00014, Helsinki, Finland.|Institute of Biomedicine, Department of Biochemistry and Developmental Biology, University of Helsinki, 00014, Helsinki, Finland.|Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA.|Charlie Norwood VA Medical Center, Augusta, GA, 30904, USA.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Itokazu
authors.affiliation: Institute of Biomedicine, Department of Biochemistry and Developmental Biology, University of Helsinki, 00014, Helsinki, Finland.|Department of Physiology, Kanazawa Medical University, Ishikawa, 920-0293, Japan.
authors.forename: Nobuyoshi
authors.initials: N
authors.lastname: Tajima
authors.affiliation: Institute of Biomedicine, Department of Biochemistry and Developmental Biology, University of Helsinki, 00014, Helsinki, Finland.|Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Kerosuo
authors.affiliation: Institute of Biomedicine, Department of Biochemistry and Developmental Biology, University of Helsinki, 00014, Helsinki, Finland.
authors.forename: Pentti
authors.initials: P
authors.lastname: Somerharju
authors.affiliation: Institute of Biomedicine, Department of Biochemistry and Developmental Biology, University of Helsinki, 00014, Helsinki, Finland.
authors.forename: Hannu
authors.initials: H
authors.lastname: Sariola
authors.affiliation: Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA.|Charlie Norwood VA Medical Center, Augusta, GA, 30904, USA.
authors.forename: Robert K
authors.initials: RK
authors.lastname: Yu
authors.affiliation: Department of Biosciences, University of Helsinki, Biocenter 3, P.O. Box 65, 00014, Helsinki, Finland. reijo.kakela@helsinki.fi.|Institute of Biomedicine, Department of Biochemistry and Developmental Biology, University of Helsinki, 00014, Helsinki, Finland. reijo.kakela@helsinki.fi.
authors.forename: Reijo
authors.initials: R
authors.lastname: Käkelä
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005732:Gangliosides / Q000032:analysis / Q000378:metabolism*; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis / Q000378:metabolism*; D008563:Membrane Lipids / Q000032:analysis / Q000378:metabolism*; D051381:Rats; D013116:Spinal Cord / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D013234:Stem Cells / Q000737:chemistry / Q000378:metabolism*
chemical_list: C000614142:Gfap protein, rat; D005732:Gangliosides; D005904:Glial Fibrillary Acidic Protein; D008563:Membrane Lipids; C062875:ganglioside A2B5
keywords: A2B5 antigen; Astrocyte; Glial fibrillary acidic protein; Glial progenitor/precursor cell; Lipidomics; Mass spectrometry; Phospholipid; Sphingolipid