Department of Immunology, Faculty of Medicine, Imperial College London, London, United Kingdom.
J Infect Dis. 2010 Aug 15;202(3):374-85. doi: 10.1086/653736.
Infection with human immunodeficiency virus (HIV) results in a chronic infection that progressively impairs the immune system. Although depletion of CD4(+) T cells is frequently used to explain immunosuppression, chronicity of infection and progressive loss of CD4(+) T cells are not sufficient to fully account for immune dysregulation. Arginase-induced l-arginine deprivation is emerging as a key mechanism for the down-regulation of immune responses. Here, we hypothesized that the level of arginase activity increases with disease severity in HIV-seropositive patients. We determined the levels of arginase activity in peripheral blood mononuclear cells from HIV-seropositive patients and uninfected control participants. Our results show that peripheral blood mononuclear cells from HIV-seropositive patients with low CD4(+) T cell counts expressed statistically significantly higher levels of arginase activity, compared with patients with high CD4(+) T cell counts or uninfected control participants. Furthermore, we found a statistically significant correlation between high level of arginase activity and high viral load in HIV-seropositive patients.
人类免疫缺陷病毒 (HIV) 感染会导致慢性感染，逐渐损害免疫系统。尽管 CD4(+) T 细胞耗竭常被用来解释免疫抑制，但感染的慢性和 CD4(+) T 细胞的逐渐丧失不足以完全解释免疫失调。精氨酸酶诱导的 l-精氨酸耗竭正在成为下调免疫反应的关键机制。在这里，我们假设精氨酸酶活性的水平随着 HIV 血清阳性患者疾病的严重程度而增加。我们测定了 HIV 血清阳性患者和未感染对照参与者外周血单个核细胞中的精氨酸酶活性水平。我们的结果表明，与高 CD4(+) T 细胞计数的患者或未感染对照参与者相比，低 CD4(+) T 细胞计数的 HIV 血清阳性患者外周血单个核细胞表达的精氨酸酶活性水平统计学上显著更高。此外，我们发现 HIV 血清阳性患者中精氨酸酶活性水平与高病毒载量之间存在统计学显著相关性。
