title: Expression of dentin sialoprotein (DSP) and other molecular determinants by a new cell line from dental papillae, MDPC-23.
abstract: The purpose of this study was to characterize the molecular expression of a spontaneously immortalized and cloned cell line (MDPC-23) derived from 18-19 day CD-I fetal mouse molar dental papillae to determine if these cells were odontoblast-like. Western blots showed that a protein band, at approximately 105 kDa, reacting positively with anti-DSP antibodies and co-migrating with mouse DSP, was present in lysates of cells from passages 7, 37 and 77, in serum-free conditioned medium from passage 37 cells, and in mouse dentin extract. A minor band at 55 kDa was also apparent in cell lysates. Using a cDNA probe for a 486bp mouse DSP coding sequence, DSP or DSP-PP mRNA expression was detected by Northern analysis as well as Southern analysis after RT-PCR in all three passages. It was also shown that in these cells 1,25 (OH)2 vitamin D3 upregulated both osteopontin and osteocalcin mRNA, and dexamethasone downregulated alkaline phosphatase and alpha2(I) collagen mRNA. Thus, MDPC-23 cells express proteins which are common to mineralizing tissue. The expression of DSP and DSP-PP strongly suggests that this cell line is from the odontoblast lineage.
authors.affiliation: Department of Oral Medicine, Pathology, Medicine and Surgery, University of Michigan School of Dentistry, Ann Arbor 48109, USA.
authors.forename: Z L
authors.initials: ZL
authors.lastname: Sun
authors.forename: D N
authors.initials: DN
authors.lastname: Fang
authors.forename: X Y
authors.initials: XY
authors.lastname: Wu
authors.forename: H H
authors.initials: HH
authors.lastname: Ritchie
authors.forename: C
authors.initials: C
authors.lastname: Bègue-Kirn
authors.forename: J C
authors.initials: JC
authors.lastname: Wataha
authors.forename: C T
authors.initials: CT
authors.lastname: Hanks
authors.forename: W T
authors.initials: WT
authors.lastname: Butler
mesh_terms: D000818:Animals; D002460:Cell Line; D003771:Dental Papilla / Q000166:cytology / Q000378:metabolism*; D016326:Extracellular Matrix Proteins; D051379:Mice; D015675:Osteocalcin / Q000096:biosynthesis; D053495:Osteopontin; D010750:Phosphoproteins; D011498:Protein Precursors; D012795:Sialoglycoproteins / Q000096:biosynthesis* / Q000235:genetics; D000099311:Dentin Sialophosphoprotein
chemical_list: D016326:Extracellular Matrix Proteins; D015675:Osteocalcin; D053495:Osteopontin; D010750:Phosphoproteins; D011498:Protein Precursors; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein; C506896:Spp1 protein, mouse