Pre-clinical development of an influenza vaccine to induce broad protection through multiple immune mechanisms

迫切需要一种通用流感疫苗，以预防下一次流感大流行，并更好地预防季节性流感。目前使用的疫苗并不像我们希望的那样有效，即使在某些年份，疫苗的成分与同一流感季节流行并引起疾病的流感病毒非常匹配。就像2014-15年发生的那样，大约每20年就有一年出现不匹配，结果是，与去年相比，美国因流感需要住院治疗的老年人数量增加了一倍，据报道，儿童死亡人数也异常高。目前正在进行研制能够对抗所有流感病毒的疫苗的研究。两种最先进的方法都依赖于靶向病毒的保守区域；诱导抗体对抗血凝素干细胞，或识别内部抗原核蛋白（NP）和基质蛋白1 （M1）的T细胞。牛津大学在T细胞增强疫苗的临床开发方面处于领先地位；西奈山医院一直处于抗干细胞抗体研究的前沿。MVA-NP+M1单次免疫可增强年轻人和老年人的T细胞应答，目前一项使用MVA和ChAdOx1表达NP+M1的临床研究显示，免疫后强烈T细胞应答持续时间延长，这对维持保护性免疫很重要。在两次免疫后，Mount Sinai已经能够获得针对HA干细胞的保护性抗体滴度，但是每次免疫必须递送不同版本的嵌合HA （cHA）分子。我们现在建议合作生产同时利用免疫机制（抗体和T细胞）的疫苗，以生产最终的通用流感疫苗。我们将生产和测试复制缺陷病毒载体（类人猿腺病毒ChAdOx1和修饰痘苗病毒安卡拉MVA），表达来自2组甲型流感病毒的cHA分子和已用于临床试验的NP+M1融合蛋白。在每个病毒载体中使用不同版本的cHA将使我们能够诱导针对HA干细胞的保护性抗体反应，同时增强和维持针对NP和M1的保护性T细胞反应。我们还将测试使用重组cHA蛋白来提高抗干细胞抗体。我们将在小鼠和雪貂中进行免疫原性和有效性测试，并生产适合cGMP生产和临床测试的pre-GMP疫苗和/或细胞库。这将使我们能够在完成临床前研究后很快进行临床试验。

There is an overwhelming need for a universal influenza vaccine to protect against the next influenza pandemic as well as providing improved protection against seasonal influenza. Vaccines that are currently in use are not as effective as we would like them to be even in years when the composition of the vaccines is a good match for the influenza viruses that are circulating and causing illness in the same influenza season. Approximately one year in every 20 there is a poor match, as has happened in 2014-15, and as a result twice as many older adults have required hospital treatment for influenza in the US compared to last year, with an unusually high number of deaths in children also being reported. Research is being conducted into making vaccines that will work against all influenza viruses. The two most advanced approaches both rely on targeting conserved regions of the virus; inducing antibodies against the haemagglutinin stem, or T cells recognizing the internal antigens nucleoprotein (NP) and matrix protein 1 (M1). Oxford has taken the lead in clinical development of T cell boosting vaccines; Mount Sinai has been at the forefront of anti-stem antibody research. A single immunization with MVA-NP+M1 boosts T cell responses in young and older adults, and a current clinical study using both MVA and ChAdOx1 to express NP+M1 has shown increased duration of strong T cell responses following immunization, which will be important to maintain protective immunity. Mount Sinai have been able to achieve protective antibody titres against HA stem after two immunisations, but different versions of the chimeric HA (cHA) molecule must be delivered with each immunization.We now propose to collaborate to produce vaccines which employ both mechanisms of immunity (antibodies and T cells) in order to produce the ultimate universal influenza vaccine. We will produce and test replication-deficient viral vectors (simian adenovirus ChAdOx1 and Modified Vaccinia virus Ankara MVA) expressing both a cHA molecule derived from a group 2 influenza A virus and the NP+M1 fusion protein that has been used in clinical trials. Using a different version of cHA in each viral vector will allow us to induce protective antibody responses against HA stem at the same time as boosting and maintaining protective T cell responses against NP and M1. We will also test the use of recombinant cHA protein to boost anti-stem antibodies.We will conduct immunogencity and efficacy testing in mice and ferrets, and produce pre-GMP vaccine and/or cell banks suitable for cGMP manufacture and clinical testing. This will allow us to pregress to clinical trials very soon after the completion of this pre-clinical study.