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Adhesion, growth and differentiation markers in human osteoblast-like cells cultured on surface-modified metallic materials designer for bone implants

Bacakova L., Kabatova J., Lisa V., Stary V., Fencl J.

Inżynieria Biomateriałów

2006

R. 9, nr 58-60

1-3

A series of metallic materials with different surface treatments were prepared: pure machined titanium (T), titanium polished by diamond paste (TL), machined Ti6Al4V alloy (TS), Ti6Al4V alloy polished by diamond paste (TSL), Ti5Al2.5Fe alloy treated by electro-erosion (A) and Ti5Al2.5Fe plasma-sprayed with Ti (PL). The materials were seeded with human osteoblast-like cells MG 63. One day after seeding, the highest cell numbers were obtained on the samples of medium surface roughness (T and TS; Ra 0.63-0.30 um and 0.89-0.57 um, respectively). From day 1 to 4, the cell proliferation was the quickest on the samples with the lowest surface roughness (TL and TSL; Ra 0.17-0.13 for both materials). The cells on TL also contained the highest concentration of integrin adhesion molecules with alpha V chain, i.e. receptors for vitronectin and fibronectin. One day 8 after seeding, the cell on all metallic samples as well as tissue culture polystyrene reached similar population densities. The cells on electro-eroded Ti5Al2.5Fe (samples A; Ra 15.27-0.74 um) contained the highest concentration of osteocalcin and osteopontin, i.e. markers of osteoblastic differentiation. Thus, the latter newly developed material could be considered as promising for construction of bone implants well anchored in the surrounding bone tissue.

Pro-angiogenic effects of X-rays on murine endothelial cells

Lisiak E., Dziekiewicz M., Meineke V., Bilski M., Janiak M.

Nukleonika

2005

Vol. 50,suppl.2

17-20

Recently, significant attention has been paid to the possibility of thwarting cancer progression by inhibition of neoangiogenesis (formation of new blood vessels) in growing tumors. Although general mechanisms of angiogenesis have been elucidated, virtually nothing is known about the effects of low doses of ionizing radiation on pro-angiogenic properties of endothelial cells. In the present study, we evaluated the effects of a low (0.2 Gy), intermediate (1 Gy), and high (4 Gy) doses of X-rays on a few angiogenesis-related parameters of isolated murine endothelial cells. We show here that 24 to 48 hours after irradiation with 0.2 Gy the cell proliferation was inhibited to a similar extent as after the exposure to 1 Gy. Also, adhesion of the 0.2 Gy-irradiated cells to both gelatin and MatrigelŽ was inhibited 24 hours post-exposure, whereas irradiation with 1 or 4 Gy resulted in the increased adhesion of the cells to these substrata. Similar effects were observed during the "wound" migration assay. Finally, 24 hours after exposure of the cells to 0.2 Gy of X-rays, the surface expression of the â3 integrin subunit was down-regulated, whereas irradiations with 1 and 4 Gy of X-rays resulted in the significantly elevated expression of this subunit. These results indicate that proliferating endothelial cells are sensitive in vitro to relatively low doses of ionizing radiation