McGrath M S, Santulli S, Gaston I
Department of Medicine, University of California, San Francisco.
AIDS Res Hum Retroviruses. 1990 Aug;6(8):1039-43. doi: 10.1089/aid.1990.6.1039.
GLQ223 is a formulated version of tricosanthin, a single-chain ribosome-inactivating protein that was shown in earlier studies to inhibit human immunodeficiency virus (HIV) replication in T-lymphoblastoid cells and to decrease HIV p24 levels in HIV-infected monocyte-derived macrophages as measured by flow cytometry. The current studies were performed to test the selectivity of the observed inhibitory effects on HIV replication in chronically infected macrophages infected in vitro. Peripheral blood-derived monocyte/macrophages were infected in vitro and cultivated in suspension for at least two weeks prior to GLQ223 treatment. Anti-HIV effects were quantitated by measurement of cytoplasmic HIV p24, by both enzyme-linked immunosorbent assay (ELISA) and flow cytometry and HIV RNA levels were measured by slot blot analysis. Incorporation of [3H]leucine into trichloroacetic acid- (TCA) precipitable protein was also evaluated as an index of nonspecific inhibitory effects mediated by the compound in infected and uninfected cultures. Five days after a single 3-h treatment with GLQ223 there was a concentration-dependent decrease in all measurable HIV parameters within infected cultures. The anti-HIV effects persisted at least 28 days without evidence for increasing HIV expression. GLQ223 treatment of parallel uninfected macrophage cultures showed no significant inhibition of tritiated leucine uptake. These experiments demonstrate that a single pulsed exposure with GLQ223 of macrophages infected with HIV in vitro caused a sustained, concentration-dependent decrease in both HIV p24 antigen levels as well as HIV RNA without causing measurable toxicity in uninfected cultures.
GLQ223是天花粉蛋白的一种制剂形式，天花粉蛋白是一种单链核糖体失活蛋白，早期研究表明它能抑制T淋巴母细胞中的人类免疫缺陷病毒（HIV）复制，并通过流式细胞术检测发现其能降低HIV感染的单核细胞衍生巨噬细胞中的HIV p24水平。当前的研究旨在测试GLQ223对体外慢性感染巨噬细胞中HIV复制的抑制作用的选择性。外周血来源的单核细胞/巨噬细胞在体外感染，并在GLQ223处理前悬浮培养至少两周。通过酶联免疫吸附测定（ELISA）和流式细胞术测量细胞质HIV p24来定量抗HIV效果，并通过斑点杂交分析测量HIV RNA水平。将[3H]亮氨酸掺入三氯乙酸（TCA）沉淀蛋白中也作为该化合物在感染和未感染培养物中介导的非特异性抑制作用的指标进行评估。用GLQ223单次处理3小时后五天，感染培养物中所有可测量的HIV参数均呈浓度依赖性下降。抗HIV效果持续至少28天，且无HIV表达增加的证据。对平行的未感染巨噬细胞培养物进行GLQ223处理未显示出对氚化亮氨酸摄取的显著抑制。这些实验表明，体外对感染HIV的巨噬细胞单次脉冲暴露GLQ223会导致HIV p24抗原水平和HIV RNA均持续、浓度依赖性下降，且不会在未感染培养物中产生可测量的毒性。
