Conditionally Immortalized Retinal Capillary Endothelial Cell Lines (TR-iBRB) Expressing Differentiated Endothelial Cell Functions Derived from a Transgenic Rat
摘要
The objective of this study was to establish and characterize a retinal capillary endothelial cell line (TR-iBRB) from a newly developed transgenic rat harboring the temperature-sensitive simian virus 40 (SV 40) large T-antigen gene (Tg rat). Retinal capillary endothelial cells were isolated from a Tg rat and cultured in collagen-coated dishes at 37°C for a period of 48hr. Cells were subsequently cultured at 33°C to activate the large T-antigen. At the third passage, cells were cloned by colony formation and isolated from other cells. Nine immortalized cell lines of retinal capillary endothelial cells (TR-iBRB1
9) were obtained from a Tg rat. These cell lines had a spindle-fiber shape morphology, expressed the typical endothelial marker, von Willebrand factor, and internalized acetylated-low density lipoprotein. Moreover, vascular endothelial growth factor (VEGF) receptor-2 was expressed in TR-iBRBs. TR-iBRBs expressed a large T-antigen and grew well at 33°C with a doubling time of 19–21hr. In contrast, cells did not grow at 37 and 39°C due to the reduced expression of large T-antigen, supporting temperature-dependent cell growth. TR-iBRBs expressed GLUT1 and exhibited 3- O -methyl- D -glucose (3-OMG) uptake activity. This 3-OMG uptake was saturable with a Michaelis–Menten constant of 5.56±0.51m M and a maximum uptake rate of 45.3±2.6nmolmin−1mg protein−1. P-Glycoprotein, with a molecular weight of 180KDa, was expressed in TR-iBRBs. In addition, mdr 1a, mdr 1b andmdr 2 were detected in TR-iBRB2 using RT-PCR. In conclusion, conditionally immortalized retinal capillary endothelial cell lines were established from a transgenic rat harboring the temperature-sensitive SV 40 large T-antigen gene and these lines were shown to exhibit the properties of retinal capillary endothelial cells.
9) were obtained from a Tg rat. These cell lines had a spindle-fiber shape morphology, expressed the typical endothelial marker, von Willebrand factor, and internalized acetylated-low density lipoprotein. Moreover, vascular endothelial growth factor (VEGF) receptor-2 was expressed in TR-iBRBs. TR-iBRBs expressed a large T-antigen and grew well at 33°C with a doubling time of 19–21hr. In contrast, cells did not grow at 37 and 39°C due to the reduced expression of large T-antigen, supporting temperature-dependent cell growth. TR-iBRBs expressed GLUT1 and exhibited 3- O -methyl- D -glucose (3-OMG) uptake activity. This 3-OMG uptake was saturable with a Michaelis–Menten constant of 5.56±0.51m M and a maximum uptake rate of 45.3±2.6nmolmin−1mg protein−1. P-Glycoprotein, with a molecular weight of 180KDa, was expressed in TR-iBRBs. In addition, mdr 1a, mdr 1b andmdr 2 were detected in TR-iBRB2 using RT-PCR. In conclusion, conditionally immortalized retinal capillary endothelial cell lines were established from a transgenic rat harboring the temperature-sensitive SV 40 large T-antigen gene and these lines were shown to exhibit the properties of retinal capillary endothelial cells.