ObjectiveTo explore the effect of fetal bovine serum (FBS) of different concentrations in the culture medium on osteogenic growth peptide (OGP) promoting bone marrow mesenchymal stem cells (BMSCs) proliferation and differentiation. MethodsBMSCs were separated from limb bones of 8 Sprague Dawley rats (5 weeks old) and purified by adherence method, and BMSCs at passage 3 were divided into 4 groups according to OGP concentration: OGP 1×10-10 mol/L group, OGP 1×10-9mol/L group, OGP 1×10-8 mol/L group, and control group without OGP; and 0, 2%, 5%, 8%, and 10%FBS concentration gradient was used in each group. The cell proliferation rate was detected by MTT method at 1, 3, 5, 7, 9, and 12 days after culture, and the activity of intracellular alkaline phosphatase (ALP) was determined by the method of p-nitrophenyl phosphate disodium at 9 days after culture. ResultsBMSCs showed adherent growth, rapid proliferation, long fiber vortex, and typical morphology. MTT analysis showed that cells could not sustain proliferation when FBS concentration was less than 5% in each group; when FBS concentration was above 8%, cells proliferated continually. Proliferation promoting effect of OGP 1×10-8 mol/L and 1×10-9 mol/L groups was significantly higher than that of the control group in all serum concentrations (P<0.05); when FBS concentration was lower than 10%, the proliferation promoting effect of OGP 1×10-8 mol/L group was significantly higher than that of the other 2 OGP groups (P<0.05), but when FBS concentration was 10%, OGP 1×10-8 mol/L group had no advantage of promoting proliferation. ALP test results showed that as the FBS concentration increased, ALP activity of all groups also significantly increased (P<0.05). Under the condition of 5%FBS and 8%FBS, the ALP activity of each OGP group was significantly greater than that of the control group, and it was the highest in OGP 1×10-8 mol/L group (P<0.05). Under the condition of 10%FBS, the ALP activity of each OGP group was still greater than that of the control group (P<0.05), but no significant difference was found between the OGP 1×10-8 mol/L group and OGP 1×10-9 mol/L group (P>0.05). ConclusionThe concentration of 8%FBS is the best concentration of serum for OGP promoting the proliferation and differentiation of BMSCs, and the most suitable concentration of promoting the proliferation and differentiation of BMSCs is OGP 1×10-8 mol/L.
Objective Neuron purification is essential to procedure of various nerve cell experimental research, however, at present there is few reports on the effect of various factors on neural axons during purification. To find out a simple method of neuron purification, and to investigate the influence factors of corresponding purification culture in dorsal root gangl ion (DRG) tissue culture on β3-tubul in positive axon. Methods The DRGs were obtained from the 3 days neonatal SD rat microscopically and were made into cell suspension. Then, the amount of attached DRG neurons and non neuronal cells in poly-D-lysine (PDL) group, PDL/Laminin (PDL/LN) group and collagen-I (Col I) group was observed from 10 to 100 minutes. Then, the extension and arborization of β3-tubul in positive axons were observed after 72 hours completely randomised DRG tissue culture for the research of the influences among culture substrates (PDL, PDL/LN, and Col I), FBS (0, 5%, and 10%), 5 fluorouracil (5-Fu, 0, 20, and 40 μmol/L), and cytrarabine (Ara-C, 0, 10, and 20 μmol/L). Results Adherent cells were observed instantly after inoculation by inverted phase contrast microscope and inverted fluoresence microscope; after cell suspension was removed, adherent growth of DRGn cells and non-DRGn cells were still seen. In PDL group, the amount of NSE negative cells was significantly higher than that of NSE positive cells at 10 and 30 minutes (P lt; 0.05); the amount of NSE positive cells was significantly higher than that of NSE negative cells at 80, 90 and 100 minutes (P lt; 0.05). In PDL/LN gruop, there was no significant difference (P gt; 0.05) in the amount of NSE negative cells and NSE positive cells at 10, 20, 30, 40, and 50 minutes; the amount of NSE positive cells was significantly higher (P lt; 0.05) than that of NSE negative cells at 60, 70, 80, 90, 100 minutes. In Col I group, the amount of NSE negative cells was higher than that of NSE positive cells at 10-40 minutes, but showing no significant difference (P gt; 0.05); the amount of NSE positive cells was significantly higher (P lt; 0.05) than that of NSE negative cells at 70-100 minutes. At 72 hours after DRG tissue culture, the best result of β3-tubul in positive axon extension and arborization was obtained when the substrate level was PDL/LN, and the average length of PDL/LN level was significantly larger than that of other two substrates (P lt; 0.05). The highest number of β3-tubul in positive axon distal end was obtained at 5% concentration level of FBS (P lt; 0.05), but showing no significant differences in β3-tubul in positive axon length among three levels (P gt; 0.05). Both the most of β3-tubul in positive axon distal ends and the longest β3-tubul in positive axon average length were obtained at 0 μmol/L concentration level of 5-Fu, showing significant differences between 0 μmol/L level and 20, 40 μmol/L levels (P lt; 0.05). A similar result of β3-tubul in positive axon distal end was got at the 0 μmol/L level and 10 μmol/L level of Ara-C, which was significantly higher than that of 20 μmol/L level (Plt; 0.05). Conclusion? A purified DRG neuron suspension for neuron culture could be obtained via PDL differential attachment for 30 minutes. When DRG neuron culture, neuron special medium, PDL/LN substrate and 10 μmol/L Ara-C are recommended in β3-tubul in positive axon research.
Objective To investigate the possibility of culturing human oral keratinocyte using autologous serum in order to provide theoretical and technical foundation for clinical application of tissue engineering oral mucosa epithelium.Methods The human oral keratinocytes were cultured by the medium containing different concentrations of autologous serum(10%,20%,30%)and fetalbovine serum (10%), respectively. The growth conditions for the cell and the mucosa epithelium in the groups were observed, the cell growth curves were drawn, and the population doubling time (PDT) was counted. Results The results showed that the human oral keratinocyte could proliferate well in the medium containing autologous serum or fetal bovine serum. The differences in the 24hour clone rate and PDT were not significant. Both the area and the thickness of the cultured oral epithelium increased with the increase of the autologous serum concentration, and the difference between autologous serum and fetal bovine serum was significant, especially with the medium containing 20% autologous serum( P＜0.05) . The human nature of the cultured epithelium was demonstrated by the immunofluorescent mouse anti-HLA antigen. Conclusion The autologous serum can replace the fetal bovine serum to culture the oral keratinocyte well, and the cultured oral mucosa epithelium can be better differentiated in the autologous serum than in the fetal bovine serum.