T、B淋巴细胞联合免疫缺陷对急性高眼压小鼠视网膜神经细胞的影响

Influence of T-and B-cell-deficiency on retinal neurocytes of mice with acute ocular hypertension

目的研究T、B淋巴细胞联合缺陷对急性高眼压小鼠视网膜神经细胞的影响。方法选取重度联合免疫缺陷(SCID)小鼠和野生型C57BL/6小鼠各16只。2种小鼠分别随机取6只不做任何处理作为正常对照组,剩余10只作为模型组。采用前房穿刺的方法建立缺血-再灌注模型,每只小鼠取右眼为实验眼,左眼为模型对照眼。通过荧光金逆行标记技术,观察并计数再灌注后21d存活的视网膜神经节细胞(RGCs);同时进行视网膜切片苏木精-伊红染色,观察再灌注后21d视网膜形态并测量内核层厚度。结果正常对照组SCID小鼠和C57BL/6小鼠的RGCs形态和数量、视网膜结构及厚度均无明显差异。视网膜缺血-再灌注损伤后21d,SCID小鼠RGCs的存活率为91%±5%,C57BL/6小鼠RGCs的存活率为78%±5%,二者比较差异有统计学意义(P=0.003);SCID小鼠实验眼内核层厚度为(33.52±2.13)μm,模型对照眼为(34.06±3.00)μm,二者比较差异无统计学意义(P>0.05);C57BL/6小鼠实验眼内核层厚度为(22.44±1.70)μm,模型对照眼为(31.06±3.75)μm,二者比较差异有统计学意义(P=0.004)。结论急性高眼压模型中,T、B淋巴细胞联合免疫缺陷小鼠RGCs的存活率较高,视网膜损伤明显轻于野生型C57BL/6小鼠。

Background Recently, the study on the cause of optic nerve damage induced by glaucoma is of concern in ophthalmology. Some research showed that the immune system is associated with glaucoma-induced optic neuropathy. Acute ischemia-repeffusion is an ideal model of studying optic neuropathy. Objective The present study investigates the effect of T and B lymphocyte deficiency on the retinal neurocytes of mice with acute intraocular hypertension. Methods Sixteen SPF CB- 17/Icr. Cg-Prkdcseid Lystbg/CrlVR mice 6 -8 week-old （severe combined immunodeficiency mouse,SCID） were used in this study and 16 age-matched SPF wild type （C57BL/6） mice served as controls. The ischemia-repeffusion injury models were induced in the right eyes of 10 SCID mice and 10 C57BL/6 mice through intra-anterior chamber infusion of balanced saline solution for 45 minutes to increase the intraocular pressure to 104 mmHg,and the left eyes served as model controls. The other 6 SCID mice and 6 C57BL/6 mice served as normal control group. 10 g/L （2 ±） of FlouroGold was injected into the brains of the mice for the labeling of surviving retinal ganglion cells 21 days after ischemia-repeffusion. The thickness of retinal inner nuclear layer was measured by H＆E staining under the fluorescent microscope 21 days after ischemic insult. The use of the animals followed the Standard of Association for Research in Vision and Ophthalmology. Results In normal control mice, the morphology of retinal ganglion cells （RGCs） and retinal structure were similar between SCID mice and C57BL/6 mice. The differences in the numbers of RGCs and retinal thickness were insignificant between the two types of mice （P 〉 0.05 ）. In the experimental mice, the surviving RGCs were strikingly increased in SCID mice （91% ±5% ） compared with C57BL/6 mice （78% ±5% ） （P = 0. 003）. The thickness of the retinal inner nuclear layer was obviously thinner in the model eyes （ 22.44 ±1.70 μm） compared to model control eyes （31.06 ±3.75 μm） in C57BL/6 mice （P = 0. 004 ） , but no statistically significant difference was found between the model eyes and model control eyes in SCID mice （33.52 ±2.13μm vs 34.06 ±3.00 μm） 21 days after ischemia-reperfusion injury（P 〉 0.05）. Conclusion T and B lymphocytes deficient mice show a better tolerance to acute intraocular hypertension than the wild type C57BL/6 mice.