Biochemical and biological characterization of a dodecameric CD4-Ig fusion protein - Implications for therapeutic and vaccine strategies
Biochemical and biological characterization of a dodecameric CD4-Ig fusion protein - Implications for therapeutic and vaccine strategies
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DOI：
10.1074/jbc.m111191200
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发表时间：
2002-03-29
影响因子：
4.8
通讯作者：
Fauci, AS
中科院分区：
文献类型：
--
作者：
Arthos, J;Cicala, C;Fauci, AS
与HAART相关的药物毒性迫切需要开发新的抗HIV疗法。在病毒生命周期的进入阶段抑制病毒复制是一种有吸引力的策略，因为它可以防止从头感染。可溶性CD 4（sCD 4），这类药物中的第一个，未能抑制病毒在体内复制。至少有三个因素导致了这种失败：sCD 4在体外对大多数HIV原代分离株的中和活性较差;它在低浓度下表现出增强病毒复制的内在能力;并且它在体内表现出相对较短的半衰期。许多抗gp 120单克隆抗体，包括中和单克隆抗体，在次优浓度下也能增强病毒复制。我们对导致病毒进入的事件的理解的进展表明了可以减少这种活动的策略。我们假设，通过构建一个大的，同时结合多个gp 120的基于sCD 4的分子，并且对gp 120具有高度的亲和力，我们可以消除其增强病毒进入的能力。在这里，我们描述了一个多聚的CD 4-IgG 1融合蛋白的建设。该分子的流体动力学半径约为12 nM。它可以结合至少10个gp 120亚基，结合动力学表明对病毒体相关包膜的高度亲合力相互作用。这种蛋白质在次优浓度下不增强病毒复制。这些观察结果可能有助于设计新的治疗方法和疫苗。
Drug toxicities associated with HAART lend urgency to the development of new anti-HIV therapies. Inhibition of viral replication at the entry stage of the viral life cycle is an attractive strategy because it prevents de novo infection. Soluble CD4 (sCD4), the first drug in this class, failed to suppress viral replication in vivo. At least three factors contributed to this failure: sCD4 demonstrated poor neutralizing activity against most primary isolates of HIV in vitro; it demonstrated an intrinsic capacity to enhance viral replication at low concentrations; and it exhibited a relatively short half-life in vivo. Many anti-gp120 monoclonal antibodies, including neutralizing monoclonal antibodies also enhance viral replication at suboptimal concentrations. Advances in our understanding of the events leading up to viral entry suggest strategies by which this activity can be diminished. We hypothesized that by constructing a sCD4-based molecule that is large, binds multiple gp120s simultaneously, and is highly avid toward gp120, we could remove its capacity to enhance viral entry. Here we describe the construction of a polymeric CD4-IgG1 fusion protein. The hydrodynamic radius of this molecule is similar to12 nM. It can bind at least 10 gp120 subunits with binding kinetics that suggest a highly avid interaction toward virion-associated envelope. This protein does not enhance viral replication at suboptimal concentrations. These observations may aid in the design of new therapeutics and vaccines.