Objective: To construct a HIV-1 gp120 transgenic mouse model (gp120+) with α7 nicotinic acetylcholine receptor (α7nAChR) gene knockout.
Methods: The α7nAChR gene knockout mice (α7R-/-) were crossed with HIV-1gp120 transgenic mice (gp120+) to generate F1 generation mice. We selected the F1 mice with the genotype of α7R+/-/gp120+ to mate to obtain the F2 mice. The genotypes of the F3 mice were identified by PCR, and the protein expressions in the double transgenic animal model was analyzed by immunohistochemistry. BV2 cells were treated with gp120 protein and α7nAChR inhibitor, and the expressions of IL-1β and TNF-α were detected using ELISA.
Results: The results of PCR showed the bands of the expected size in F3 mice. Two F3 mice with successful double gene editing (α7R-/-/gp120+) were obtained, and immunohistochemistry showed that the brain tissue of the mice did not express α7 nAChR but with high gp120 protein expression. In the in vitro cell experiment, treatment with gp120 promoted the secretion of IL-1β and TNF-α in BV2 cells, while inhibition of α7nAChR significantly decreased the expression of IL-1β and TNF-α (P < 0.001).
Conclusions: By mating gp120 Tg mice with α7R-/- mice, we obtained gp120 transgenic mice with α7nAChR gene deletion, which serve as a new animal model for exploring the role of α7nAChR in gp120-induced neurotoxicity.
目的: 通过构建双基因编辑小鼠模型（α7R-/-/gp120+），为探索α7乙酰胆碱受体（α7 nAChR）介导gp120中枢神经毒性的作用和机制提供研究基础。
方法: α7 nAChR基因敲除小鼠（α7R-/-）与HIV-1 gp120转基因小鼠（gp120+）杂交（F0），从产生的F1小鼠中，选取基因型为α7R+/-/gp120+的小鼠进一步交配，得到F2小鼠。PCR法鉴定和筛选F3小鼠基因型，免疫组化分析双转基因动物模型蛋白表达；体外实验使用gp120蛋白和α7 nAChR抑制剂处理小胶质细胞，ELISA检测各组IL-1β与TNF-α表达情况。
结果: F3小鼠的PCR结果符合预期，其中有2只双基因编辑成功的小鼠。免疫组化结果显示双基因编辑小鼠（α7R-/-/gp120+）的脑组织缺乏α7 nAChR的同时高表达gp120蛋白。体外实验结果表明Gp120可促进小胶质细胞分泌IL-1β与TNF-α，而抑制α 7nAChR后IL-1β与TNF-α表达明显降低（P＜0.001）。
结论: α7R-/-/gp120+双基因修饰小鼠成功构建，且具有稳定遗传的特点，可为后续探索α7 nAChR介导gp120中枢神经毒性的作用和机制提供重要的动物模型。
Keywords: ?; HIV-1 gp120; gene knockout; transgenic mouse models; α7 nicotinic acetylcholine receptor.