Cytotoxic immunoconjugates to deplete persistent HIV reservoirs

我们将开发细胞毒性抗艾滋病毒免疫结合物，以消除持续的艾滋病毒蓄积物。这些 分子的目标是杀死产生传染性艾滋病毒的细胞。未结合的(裸体)抗体可通过 补体和Fc受体介导的效应。我们假设细胞毒性免疫结合物将 事实证明，在杀死有生产力的感染细胞方面，单抗比裸露单抗更有效。它们可能会被用来 如果在抗逆转录病毒疗法(ART)诱导的临床期间有足够的正在进行的病毒复制 延迟，或与“激活并清除”协议中的延迟扰乱代理结合使用。 有不同形式的细胞毒性免疫结合物，包括免疫毒素， 放射免疫结合物和抗体-药物结合物。每一种可能都有独特的优势或 艾滋病毒感染治疗的局限性。我们已经描述了抗HIV免疫毒素和抗体- 药物结合物，确定了最好的靶向单抗，并在小鼠和 猕猴。我们发现，虽然抗艾滋病毒免疫毒素对新城疫病毒感染者有潜在的效果 猕猴，其用途受到免疫原性的限制。药物结合物的免疫原性可能较低，但 我们发现它们的效力低于免疫毒素，而且它们可能只在细胞分裂时具有细胞毒性。 我们将优化抗HIV免疫结合物的设计，所有这些都是基于相同的抗HIV Env的单抗， 然后比较最好的免疫结合物与未结合单抗和无关单抗的效果 结合物，使用相同的分析方法。为此，我们提出了以下具体目标： 目的1.以细胞毒性为指标优化抗HIV免疫结合物的设计，比较其疗效。 我们将生产免疫原性较低的免疫毒素，更有效的抗体药物结合物和211 At- 放射免疫结合物，并比较它们对表达Env的细胞的细胞毒性。 目的2.用原代细胞培养法比较结合物和裸露单抗。我们将测试 应用抗逆转录病毒治疗患者原代培养的免疫结合物的疗效。 目的3.比较经抗逆转录病毒治疗的HIV感染者的结合物和非结合型单抗 用人造血组织重组的免疫缺陷小鼠。病毒血症与组织病毒载量 将被量化并进行病毒整合分析。 这些研究的目的是确定最有效的免疫结合物形式，用于未来的测试，作为前 新城疫病毒感染的临床候选抗逆转录病毒治疗猕猴。这些研究也与 免疫结合物在其他情况下的使用，尤其是癌症。

We will develop cytotoxic anti-HIV immunoconjugates to eliminate persistent HIV reservoirs. These molecules aim to kill cells producing infectious HIV. Unconjugated (naked) antibodies can kill cells via complement and Fc-receptor mediated effects. We hypothesize that cytotoxic immunoconjugates will prove even more effective than naked mAbs in killing productively-infected cells. They may be used alone if there is sufficient ongoing virus replication during anti-retroviral therapy (ART)-induced clinical latency, or in conjunction with latency-disrupting agents in an “activate and purge” protocol. There are different forms of cytotoxic immunoconjugates, including immunotoxins, radioimmunoconjugates, and antibody-drug conjugates. Each may have unique advantages or limitations for the treatment of HIV infection. We have described anti-HIV immunotoxins and antibody- drug conjugates, identified the best mAbs for targeting them, and shown anti-viral activity in mice and macaques. We found that while anti-HIV immunotoxins were potentially effective in SHIV-infected macaques, their utility was limited by immunogenicity. Drug conjugates may be less immunogenic, but we found them less potent than immunotoxins, and they may only be cytotoxic in dividing cells. We will optimize the design of anti-HIV immunoconjugates, all based on the same mAbs to HIV Env, then compare the efficacy of the best immunoconjugates with unconjugated mAbs and irrelevant conjugates, using the same assays. To do so, we propose the following Specific Aims: Aim 1. To optimize design of anti-HIV immunoconjugates using cytotoxicity to compare efficacy. We will produce less-immunogenic immunotoxins, more potent antibody drug conjugates and 211At- radioimmunoconjugates and compare them using cytotoxicity on Env-expressing cells. Aim 2. To compare conjugates and naked mAbs using primary cell cultures. We will test the efficacy of immunoconjugates using primary outgrowth cultures from ART-treated patients. Aim 3. To compare conjugates and unconjugated mAbs in HIV-infected, ART-treated immunodeficient mice reconstituted with human hematopoietic tissue. Viremia and tissue virus loads will be quantified and viral integration analyses performed. These studies aim to identify the most effective form of immunoconjugate for future testing as a pre- clinical candidate in SHIV-infected ART treated macaques. These studies also have relevance for the use of immunoconjugates in other conditions, especially cancer.