Majallah-i Dānishgāh-i ̒Ulūm-i Pizishkī-i Bābul (Jun 2008)
MESENCHYMAL STEM CELLS WITH HIGH GROWTH RATE IN THE SUPERNATANT MEDIUM FROM RAT BONE MARROW PRIMARY CULTURE
Abstract
BACKGROUND AND OBJECTIVE: In marrow primary culture for mesenchymal stem cell isolation, the cells suspended in supernatant are usually discarded at first medium exchange. The objective of this study was to culture and expand these cells, to examine their mesenchymal stem cell nature, to compare their growth rate with that of adherent cells of primary culture and eventually to optimize the culture conditions for the cells maximum proliferation.METHODS: In this experimental study, 10 Wistar strain rats were sacrificed, their tibial bone marrow were collected and plated in 75cm2 culture flasks. Four days after culture initiation, the supernatant medium was collected and its floating cells along with those primarily adherent cells were expanded by three successive subcultures, during which population doubling time (PDT) was calculated and statistically compared. Furthermore, culture condition including its fetal bovine serum (FBS) concentration as well as the cell density at culture initiation for maximum proliferation of the cells was optimized. The isolated cells were evaluated with respect to their potential to differentiate into bone, cartilage and adipose cells. FINDINGS: Based on our results, the population of the cells from removed medium was doubled in number each 14.9±2 hr, while this value was 19±2.1 hr for primarily adherent cell population (p<0.05). Data indicated that both cells had a maximum proliferation when cultured in a medium containing 15% FBS at 100 cell/cm2. The isolated cells were readily differentiated into skeletal cells as were evident in specific staining as well as RT-PCR analysis. CONCLUSION: Supernatant of rat’s marrow primary culture contains mesenchymal stem cells (MSCs) with high growth rate.
