BACKGROUND:Studies about low-frequency pulsed electromagnetic fields interfering with bone marrow mesenchymal stem cells proliferation and differentiation are many, but the Raman spectra of single stem cells irradiated in electromagnetic fields analyzed by surface Raman spectroscopy analysis are rarely reported. OBJECTIVE:To compare the difference in Raman spectra of bone marrow mesenchymal stem cells with or with no irradiation of 3 000 Hz pulsed electromagnetic fields. METHODS:Bone marrow mesenchymal stem cells isolated from Sprague-Dawley rats were cultured and identified. Passage 3 cells were inoculated into 6-wel plates and divided into two groups:pulsed electromagnetic field irradiation group and blank control group. After cultured for 7 days, cells in the two groups were transferred to physiological saline, and 30 cells were randomly col ected from each group. Four Raman spectra were harvested from each celland the average relative intensity of Raman spectra was calculated and compared between two groups. RESULTS AND CONCLUSION:There were the same Raman peaks in the two groups, and the waveforms were basical y same in the two group based on the curve mapping by origin 7.0 software. The peak value in the irradiation group was decreased compared with the blank control group. Laser optical tweezers Raman spectroscopy can be applied to study the biochemical changes of a single stem cellat the molecular level. The Raman spectra of bone marrow mesenchymal stem cells irradiated by 3 000 Hz pulsed electromagnetic fields differ from those without irradiation, and the peak also lowered after irradiation.

OBJECTIVE: To compare the efficiency of human bone marrow mesenchymal stem cells (hBMSCs) with rat BMSCs (rBMSCs) transfected by modified adenovirus containing fiber 35 (AdF35)-enhanced green fluorescence protein(eGFP). METHODS: We separated hBMSCs and rBMSCs from the bone marrow of humans and rats, respectively, and osteogenesis and adipogenesis were induced. eGFP was carried by modified AdF35, which was transfected to hBMSCs and rBMSCs with different multiplicity of infections (MOIs). Activity of the cells was detected by MTT. The transfected cells were observed under fluorescent microscope. The transfection efficiency was measured by flow cytometer. The expression of coxsackie and adenovirus receptor (CAR) and CD46 mRNA in the cells was inspected by real time PCR. RESULTS: hBMSCs and rBMSCs induced osteogenesis and adipogenesis successfully after being separated from human and rat bone marrow respectively. The activity of the cells was inhibited when MOI was 1,000 PFU/mL. hBMSCs with strong green fluorescence were observed but few rBMSCs were seen under fluorescence microscope 48 h after being transfected by AdF35-eGFP. The transfective efficiency was (84.8±7.1)% and (3.3±1.1)%, respectively. The expression of CD46 was high while that of CAR was low in hBMSCs. The expression of CAR was very high and that of CD46 was low in rBMSCs (P<0.01). CONCLUSION AdF35 may be the ideal vector to carry the target gene to transfect hBMSCs effectively but not to transfect rBMSCs.
Adenoviridae ; genetics ; Animals ; Bone Marrow Cells ; cytology ; metabolism ; Genetic Vectors ; Green Fluorescent Proteins ; biosynthesis ; genetics ; Humans ; Mesenchymal Stem Cells ; cytology ; metabolism ; Rats ; Transfection