相対細胞増殖率に及ぼすTi, Al, V濃度の影響

Abstract

The effects of Ti, V and Al concentrations on the relative growth ratios of L929, MC3T3-E1 cells and on the colony formation ratio of V79 cells by cell culture method with metallic powders were investigated. These powders were sterilized under U.V. lamp for 14 ks(4 h), suspended in the medium and were extracted for 173 ks(48 h), 259 ks(72 h) and 346 ks(96 h) in the incubator under a 95% air-5%CO2 atmosphere. The medium not containing any metallic powder (control) was also extracted under similar conditions. After filtering with a 0.2 μm filter, 1.0×104∼5.0×104 L929 cells/ml, 5×104 MC3T3-E1 cells/ml and 102 V79 cells/ml were seeded in control and in the filtrates of the medium containing metallic powder. The number of cells were counted using a coulter counter from 86 ks(1 d) to 605 ks(7 d). The number of L929 cells after 346 ks(4 d) of incubation were almost similar for Ti extraction and control, whereas in the case of Al and V extractions the number of cells were too low as compared to that of control. The relative growth ratios of L929 cells for Ti, Al and V after 346 ks (4 d) of incubation were about 1, 0.05 and 0.02 respectively. Also, similar trends were observed for MC3T3-E1 and V79 cells. The relative growth ratio (number of cells in test medium/number of cells in control) of L929 cells for Ti powder was almost equal to one in 1∼10 g of Ti powder. On the contrary, the relative growth ratio of L929 cells for Al decreased with the increase in the weight of Al powder from 1 g to 3 g for both Eagle’s MEM (Minimum Essential Medium not containing fetal bovine serum and 7.5%NaHCO3) and Eagle’s medium extractions. No colonies of V79 cells were found for Al. Further, the concentration of Al in the medium increased with the increase in the weight of the Al powder. The relative growth ratio of L929 cells decreased as the initial number of L929 cells increased. Moreover, dilutions from 1 to 10 times in the case of Al and from 1 to 5000 times in the case of V were made. The relative growth ratios of L929, MC3T3-E1 and V79 cells became equal to 1 at 5 times dilution for Al and at 4000 times dilution for V. As the metallic concentration of Al and V ion in the medium increased from 0.2 to 0.5 mass ppm, the relative growth ratio of L929 and colony formation ratio of V79 cells decreased from 1 to almost 0. But, for MC3T3-E1 cells, the effect from a much lower concentration of V ion (0.02 ppm) was observed.