Münch Jan, Ständker Ludger, Pöhlmann Stefan, Baribaud Frédéric, Papkalla Armin, Rosorius Olaf, Stauber Roland, Sass Gabriele, Heveker Nikolaus, Adermann Knut, Escher Sylvia, Klüver Enno, Doms Robert W, Forssmann Wolf-Georg, Kirchhoff Frank
Institute for Clinical and Molecular Virology, University of Erlangen-Nürnberg, 91054 Erlangen, Germany.
Antimicrob Agents Chemother. 2002 Apr;46(4):982-90. doi: 10.1128/AAC.46.4.982-990.2002.
Proteolytic processing of the abundant plasmatic human CC chemokine 1 (HCC-1) generates a truncated form, HCC-1[9-74], which is a potent agonist of CCR1, CCR3, and CCR5; promotes calcium influx and chemotaxis of T lymphoblasts, monocytes, and eosinophils; and inhibits infection by CCR5-tropic human immunodeficiency virus type 1 (HIV-1) isolates. In the present study we demonstrate that HCC-1[9-74] interacts with the second external loop of CCR5 and inhibits replication of CCR5-tropic HIV-1 strains in both primary T cells and monocyte-derived macrophages. Low concentrations of the chemokine, however, frequently enhanced the replication of CCR5-tropic HIV-1 isolates but not the replication of X4-tropic HIV-1 isolates. Only HCC-1[9-74] and HCC-1[10-74], but not other HCC-1 length variants, displayed potent anti-HIV-1 activities. Fluorescence-activated cell sorter analysis revealed that HCC-1[9-74] caused up to 75% down-regulation of CCR5 cell surface expression, whereas RANTES (regulated on activation, normal T-cell expressed and secreted) achieved a reduction of only about 40%. Studies performed with green fluorescent protein-tagged CCR5 confirmed that both HCC-1[9-74] and RANTES, but not full-length HCC-1, mediated specific internalization of the CCR5 HIV-1 entry cofactor. Our results demonstrate that the interaction with HCC-1[9-74] causes effective intracellular sequestration of CCR5, but they also indicate that the effect of HCC-1[9-74] on viral replication is subject to marked cell donor- and HIV-1 isolate-dependent variations.
大量存在的人CC趋化因子1（HCC-1）经蛋白水解加工后产生一种截短形式，即HCC-1[9-74]，它是CCR1、CCR3和CCR5的强效激动剂；可促进T淋巴母细胞、单核细胞和嗜酸性粒细胞的钙内流和趋化作用；并抑制CCR5嗜性1型人类免疫缺陷病毒（HIV-1）分离株的感染。在本研究中，我们证明HCC-1[9-74]与CCR5的第二个外环相互作用，并抑制CCR5嗜性HIV-1毒株在原代T细胞和单核细胞衍生巨噬细胞中的复制。然而，低浓度的趋化因子常常会增强CCR5嗜性HIV-1分离株的复制，但不会增强X4嗜性HIV-1分离株的复制。只有HCC-1[9-74]和HCC-1[10-74]，而不是其他HCC-1长度变体，表现出强效的抗HIV-1活性。荧光激活细胞分选分析显示，HCC-1[9-74]可导致CCR5细胞表面表达下调多达75%，而调节激活正常T细胞表达和分泌因子（RANTES）仅使CCR5细胞表面表达降低约40%。用绿色荧光蛋白标记的CCR5进行研究证实，HCC-1[9-74]和RANTES均可介导CCR5 HIV-1进入辅助因子的特异性内化，但全长HCC-1则不能。我们的结果表明，与HCC-1[9-74]的相互作用会导致CCR5在细胞内有效隔离，但也表明HCC-1[9-74]对病毒复制的影响存在明显的细胞供体和HIV-1分离株依赖性差异。
