HIV-1 CCR5-tropic阴道途径感染人源化BLTS小鼠模型

来源文献：Human immunodeficiency virus infection induces lymphoid fibrosis in the BM-liver-thymus-spleen humanized mouse model

PMID:30232273

DOI:10.1172/jci.insight.120430

Construction of the BLTS humanized mouse model. In Step I, NSG mice are myoablated via γ irradiation (200 rads) using a Cesium-137 irradiator. In Step II, fetal tissues (spleen, thymus, and liver) are processed into 1 mm2 pieces and transplanted as a “sandwich” under the kidney capsule in irradiated NSG mice, following the administration of antibiotic and analogesic therapy and the induction of general anesthesia. In Step III, autologous CD34+ hematopoietic stem cells are isolated from the fetal liver via magnetic selection and transplanted at 2 × 10^5cells per mouse via retro-orbital injection following kidney capsule transplantation of the lymphoid tissues. In Step IV, transplanted NSG mice were maintained under specific pathogen free conditions, and the human spleen and thymus organoids — along with other lymphoid tissues and associated immune cells — were allowed to develop over a period of 10 weeks, resulting in the BLTS humanized mouse model. 293T supernatant without HIV was used as mock control. Humanized mice with stable human leukocyte reconstitution were anesthetized and inoculated with mock or HIV-1 (~1 × 10^5 infectious units) i.v. (via retroorbital route) or via intravaginal route. ART in HIV-infected human immune system–humanized mice. Chronic HIV-infected humanized mice were treated with ART (daily i.p. injections emtricitabine [FTC, Cayman Chemicals, catalog 16879, 200 mg/ kg body weight], tenofovir disoproxil fumarate [TDF, Cayman Chemicals, catalog 16922, 200 mg/kg body weight], and raltegravir [RAL, Cayman Chemicals, catalog 16071, 80 mg/kg body weight) beginning at 8 weeks after infection for a duration of 4 weeks.

1、1. SIVmac251静脉感染恒河猴外周血病毒载量结果

8只SIVmac251静脉感染恒河猴均在感染后7d检出病毒载量阳性，之后迅速上升，在感染后14d达到高峰，峰值在107至108copies/mL之间，随后迅速下降（图1）。SIVmac251静脉感染后42d到140d感染猴的血浆载量比较稳定，1、2、3、4、9、11六只感染猴血浆病毒载量维持在105至107copies/mL之间；10号猴血浆病毒载量下降至105copies/mL以下；12号猴血浆病毒载量一直维持在较高水平，即107copies/mL以上。

图1 SIVmac251静脉感染中国恒河猴外周血病毒载量结果

Fig.1 Theviremia (viral RNA copies/ml plasma) in Chinese-original rhesus macaquesinfected intravenously with SIVmac251

1、 2. SIVmac251静脉感染恒河猴CD4+/CD8+比值结果

8只感染猴CD4+/CD8+的比例在SIVmac251静脉感染后持续下降，均于感染后14d出现倒置。2、4、10、11、12猴在感染后期一直维持在1以下的水平，其中，2、10、11三只猴维持在0.5上下波动。1、3、9三只感染猴在SIVmac251静脉感染后期CD4+/CD8+比值有些许反弹，在1.0上下波动。（图2）。

图2 SIVmac251静脉感染中国恒河猴外周血CD4+/CD8+T淋巴细胞比值

Fig.2 The changes of CD4+/CD8+ ratio of T lymphocytes in Chinese-original rhesus macaquesinfected intravenously with SIVmac251

3.SIVmac251静脉感染恒河猴CD4+ T细胞绝对数

8只感染猴CD4+细胞绝对数在SIVmac251静脉感染后迅速下降，随后发生回弹，在感染后56d下降至最低，之后维持在稳定水平（图3）。12号猴的CD4+细胞绝对数在感染后231天下降至50个/µL，出现艾滋病症状，继而死亡。4号猴的CD4+细胞绝对数在感染后259天下降至100个/µL以下；3号猴的CD4+细胞绝对数一直在800-1000个/µL上下浮动。

图3 SIVmac251静脉感染中国恒河猴外周血CD4+T淋巴细胞绝对数

Fig.3 The CD4+T cell counts (per l blood) in Chinese-origin rhesus macaques infectedintravenously with SIVmac251

所有感染动物必须在ABSL-3室中进行。

1.该模型制备比较成熟，国内外都有此模型，构建和评价指标一致，所以该模型应用广泛，具有统一的操作规程。

2. 该模型制备的关键：1）小鼠必须是重度免疫缺陷的，而且饲养环境必须洁净；2）HIV操作需要生物安全。

3.此模型具有完善的人的免疫系统，HIV感染后，具有艾滋病病人相似的临床症状，所以具有很高的比较医学应用价值。