title: Determination of the differentiation capacities of murines' primary mononucleated cells and MC3T3-E1 cells.
abstract: BACKGROUND
  The main morphological features of primitive cells, such as stem and progenitor cells, are that these cells consists only one nucleus. The main purpose of this study was to determine the differentiation capacities of stem and progenitor cells. This study was performed using mononucleated cells originated from murine peripheral blood and MC3T3-E1 cells. Three approaches were used to determine their differentiation capacities: 1) Biochemical assays, 2) Gene expression analysis, and 3) Morphological observations.
  
  
  RESULTS
  We found that both cells were able to differentiate into mature osteoblasts, as assayed by ALP activity. RT-PCR analysis showed the activation of the Opn gene after osteoblast differentiation. Morphological observations of both cells revealed the formation of black or dark-brown nodules after von Kossa staining. Nevertheless, only mononucleated cells showed the significant increase in TRAP activity characteristic of mature osteoclasts. The osteoclast-specific CatK gene was only upregulated in mononucleated cells. Morphological observations indicated the existence of multinucleated osteoclasts. Sca-1 was activated only in undifferentiated mononucleated cells, indicating that the cells were hematopoietic stem cells. In both cell lines, the housekeeping Gapdh gene was activated before and after differentiation.
  
  
  CONCLUSIONS
  The isolated mononucleated cells were able to differentiate into both osteoblasts and osteoclasts; indicating that they are stem cells. On the other hand, MC3T3-E1 cells can only differentiate into osteoblasts; a characteristic of progenitor cells.
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia.
authors.forename: Muhammad Dain
authors.initials: MD
authors.lastname: Yazid
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia.
authors.forename: Shahrul Hisham Zainal
authors.initials: SHZ
authors.lastname: Ariffin
authors.affiliation: School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia.
authors.forename: Sahidan
authors.initials: S
authors.lastname: Senafi
authors.affiliation: Department of Orthopedic, Universiti Kebangsaan Malaysia Medical Centre, Universiti Kebangsaan Malaysia, 56000 Cheras, Selangor, Malaysia.
authors.forename: Mohamad Abdul
authors.initials: MA
authors.lastname: Razak
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Universiti Kebangsaan Malaysia, 50300 Kuala Lumpur, Malaysia.
authors.forename: Rohaya Megat Abdul
authors.initials: RMA
authors.lastname: Wahab