Evaluation of vaccinia IgG (VIG) in the protection of mi

总结：目前项目的目标是用几种VIG制剂进行动物保护研究，以验证体外中和试验。研究结果将大大提高CBER简化新旧VIG产品测试的能力，并缓解目前VIG短缺的问题。这些努力将促进测试新的重组牛痘疫苗，以预防艾滋病毒-1和癌症。 具体目标是： 第1阶段：确定可用于验证我们的体外病毒中和试验的牛痘病毒株vSC 56和Wyeth的最佳剂量。我们预计死亡将在10-20天内发生。 阶段2和3：检测多种牛痘免疫球蛋白（VIG）制剂并测定其IC 50。 这将涉及确定保护50%的动物免受致命剂量的牛痘病毒感染所需的VIG浓度。 结果如下： - 研究发现，SCID小鼠比裸鼠更易感染牛痘病毒，免疫缺陷也比裸鼠严重。 - 测试的两种牛痘病毒株，Wyeth疫苗株和vSC 56，在感染后25-35天期间感染SCID小鼠（10^6 pfu/小鼠，IP）。 - 在第一项体内小鼠保护研究中，将巴克斯特和MPH VIG与未稀释或1：10和1：100稀释的VIG制剂的Wyeth牛痘病毒一起孵育。 - 未稀释的MPH VIG是完全保护性的。1：10和1：100稀释液具有部分保护作用。他们将动物死亡时间推迟了1-2周。 - 巴克斯特VIG（4 oC批次）的保护性低于MPH。用未稀释的制剂和1：10的VIG稀释液观察到一例死亡。1：100稀释液没有显著保护作用。 正在进行的研究： - 使用Wyeth牛痘病毒和巴克斯特和MPH VIG制备物的多重稀释液（1：4系列稀释液）重复第一项研究。 - 使用vSC 56病毒（用于体外中和试验的病毒株）进行的类似保护研究。 - VIG亚类在体内保护中的测试。 - 在体外试验中检测显示具有高牛痘中和滴度的IVIG批次保护SCID小鼠免受牛痘感染的能力。

Summary: The goal of the current project is to conduct an animal protection study with several VIG preparations in order to validate the in vitro neutralization assay. The results will greatly enhance the ability of CBER to streamline the testing of old and new VIG products and to alleviate the current shortage of VIG. These efforts will promote the testing of new recombinant vaccinia-based vaccines against HIV-1 and cancer. The specific goals are: Stage 1: To establish the optimal dose of vaccinia strains vSC56 and Wyeth that can be used to validate our in vitro viral neutralization assay. We expect death to occur within 10-20 days. Stage 2 and 3: To test multiple preparations of Vaccinia Immunoglobulins (VIG) and determine their IC50. This will involve determining the concentration of VIG required to protect 50 percent of the animals from a lethal dose of vaccinia virus infection. Results: - SCID mice were found to be more susceptible to vaccinia infection than nude mice.The immunodeficiency of SCID mice is more severe than that of the nude mice. - Both strains of vaccinia that were tested, Wyeth vaccine strain and vSC56, killled SCID mice between 25-35 days post infection (10^6 pfu/mouse, IP). - In the first in vivo mouse protection study, Baxter and MPH VIG were incubated with Wyeth vaccinia virus, either undiluted or at 1:10 and 1:100 dilutions of the VIG preparations. - Undiluted MPH VIG was completely protective. 1:10 and 1:100 dilutions were partially protective. They postponed animal death by 1-2 weeks. - The Baxter VIG (4oC lot) was less protective than the MPH. one death was observed with undiluted preparation and 1:10 VIG dilution. The 1:100 dilution was not significantly protective. On going studies: - Repeat of the first study using the Wyeth vaccinia virus and multiple dilutions of Baxter and MPH VIG preparations (1:4 serial dilutions). - Similar protection study using vSC56 virus (the virus strain which is used in the in vitro neutralization assays). - Testing of VIG subclasses in in vivo protection. - Testing of IVIG lots that were shown to have high vaccinia neutralization titers in the in vitro assay for their capacity to protect SCID mice from vaccinia infection.