Respiration rate of rat osteoblasts in varied in vitro culture methods
Song F., Mei GY., Song KD., Jiang LL., Wen PF., Liu TQ., Ma XH., Cui ZF.
Background: Tissue-engineered seed cells combined with microcapsule technique are widely used in cell therapy, gene therapy and drug controlled release to detect consumed oxygen and respiration rates of osteoblasts. This method can provide a related theoretical basis for osteoblast in vitro culture, amplification and three-dimensional construction of engineered bone tissues, as well as above-mentioned experiments. Objective: To compare consumed oxygen qualities and respiration rates of osteoblasts cultured in static direct culture and cyst culture in vitro. Design, Time and Setting: The control experiment was performed at the Research and Development Center for Stem Cells and Tissue Engineering (i.e. National Key Laboratory of Fine Chemicals), Dalian University of Technology, Liaoning Province, China from March to September 2007. Materials: Ten 2-3 days SD rats of SPF grade and both genders were selected. Sodium polymannuronate solution was purchased from Tianjin Yuanhang, China. Methods: Cranial bone was sterilely obtained from each rat, sliced into 1 mm×1 mm blocks. Sections were digested with 2.5 g/L trypsin solution and 1 g/L type II collagenase, incubated in DMEM containing bovine calf serum of 0.1 volume fraction. When at the density of 10 9 L -1 , cells were incubated in T-25 medium. At the second and third passages, cells were cultured directly in culture flasks or encapsulated cultured by calcium alginate microcapsules. Main Outcome Measures: Adhesion, extension and distribution of osteoblasts in culture flasks or during encapsulated culture under an inverted phase contrast microscope; cell growth curve; biological function and respiration rates of osteoblasts in different culture fashions. Results: Primary culture of osteoblasts was adhered to the flask, showing spindle and polygonal. After encapsulated culture, osteoblasts were round and evenly distributed. Biological function of in vitro cultured osteoblasts was good. The outcomes of in vitro static direct culture and encapsulated culture were good. Respiration rates were 5.56×l0 -6 μ mol/min and 1.25×l0 -7 μ mol/min, respectively. Conclusion: Consumed oxygen qualities and respiration rates of osteoblasts were higher in the in vitro direct culture compared with the encapsulated culture. Varied biological functions of osteoblasts in both cultures are good, which can provide significant instruction for further studies on seed cells in tissue engineering.