Kano Tetsuya, Abe Toshiaki, Tomita Hiroshi, Sakata Tsuneaki, Ishiguro Sei-ichi, Tamai Makoto
Department of Ophthalmology, Tohoku University, School of Medicine, Miyagi, Japan.
Invest Ophthalmol Vis Sci. 2002 Dec;43(12):3744-53.
Brain-derived neurotrophic factor (BDNF) has been reported to protect retinal neurons against ischemia and light-induced damage. In the current study, the BDNF gene was transfected into iris pigment epithelial (IPE) cells of Long-Evans rats, and the neuroprotective ability of the IPE cells transfected with the BDNF gene against N-methyl-D-aspartate (NMDA)-induced neuroretinal cell death and against phototoxic damage was examined.
The level of BDNF mRNA and protein expressed in the transfected cells was determined by reverse transcription-polymerase chain reaction (RT-PCR) and by sandwich enzyme-linked immunosorbent assay (ELISA). The neuroprotective effects were determined by culturing BDNF gene-transfected IPE cells or nontransfected cells with neuroretinal cells in the presence of NMDA. The neuroprotective activity was also evaluated for the damage induced by constant exposure to light on the photoreceptors by transplanting BDNF gene-transfected IPE cells into the subretinal region of the superior half of the eye.
BDNF gene-transfected IPE cells expressed higher levels of BDNF mRNA and protein than did nontransfected IPE cells. A significant increase in the protection against NMDA was observed in the neuroretinal cells cultured with BDNF-transfected IPE cells than in those cultured with nontransfected IPE cells (P = 0.0029) or with nontreated cells (P = 0.0010). The effect was partially attenuated by the addition of anti-BDNF antibody. Significant photoreceptor cell protection against injury from constant light was also observed by the subretinal transplantation of BDNF-transfected IPE cells when compared with those receiving transplants of nontransfected cells or vehicle injection.
BDNF-transfected IPE cells demonstrated a neuronal rescue effect in both in vitro and in vivo experiments. IPE cells may be a potential source for autologous cell transplantation for some retinal diseases, and the transfection of the genes of neurotrophic factors into the transplanted cell may be a useful tool for delivering these factors to the retina.
据报道，脑源性神经营养因子（BDNF）可保护视网膜神经元免受缺血和光诱导损伤。在本研究中，将BDNF基因转染到长 Evans 大鼠的虹膜色素上皮（IPE）细胞中，并检测转染了BDNF基因的IPE细胞对N-甲基-D-天冬氨酸（NMDA）诱导的神经视网膜细胞死亡及光毒性损伤的神经保护能力。
通过逆转录聚合酶链反应（RT-PCR）和夹心酶联免疫吸附测定（ELISA）来测定转染细胞中BDNF mRNA和蛋白的表达水平。通过在NMDA存在的情况下，将转染了BDNF基因的IPE细胞或未转染的细胞与神经视网膜细胞共培养来确定神经保护作用。通过将转染了BDNF基因的IPE细胞移植到眼上半部分的视网膜下区域，还评估了持续光照对光感受器诱导损伤的神经保护活性。
转染了BDNF基因的IPE细胞比未转染的IPE细胞表达更高水平的BDNF mRNA和蛋白。与用未转染的IPE细胞（P = 0.0029）或未处理的细胞（P = 0.0010）共培养的神经视网膜细胞相比，在用转染了BDNF的IPE细胞共培养的神经视网膜细胞中，观察到对NMDA的保护作用显著增加。添加抗BDNF抗体后，该作用部分减弱。与接受未转染细胞移植或注射赋形剂的细胞相比，通过转染了BDNF的IPE细胞的视网膜下移植，也观察到对持续光照损伤的光感受器细胞有显著保护作用。
转染了BDNF的IPE细胞在体外和体内实验中均表现出神经元拯救作用。IPE细胞可能是某些视网膜疾病自体细胞移植的潜在来源，并且将神经营养因子基因转染到移植细胞中可能是将这些因子递送至视网膜的有用工具。
