Nucleoside-modified mRNA vaccine for prevention and treatment of genital herpes

摘要 生殖器疱疹影响着全球6.5亿人。迫切需要疫苗来预防感染和治疗 已经被感染的人。在当前的资金周期中，我们开发了一种候选疫苗，用于预防 使用包裹在脂质纳米粒(LNP)中的核苷修饰的mRNA表达的生殖器疱疹 单纯疱疹病毒2型(HSV-2)糖蛋白C、D和E(GC2、GD2、GE2)。疫苗针对的是一名入境者 分子GD2，以及两个免疫逃逸分子GC2和GE2。我们的候选疫苗将进入第一阶段 2022年12月进行人体试验。我们的新目标是定义免疫相关的保护 使用我们在此拨款周期内从免疫小鼠和豚鼠收集的血清进行的三价疫苗，并 开发一种基于信使核糖核酸的疫苗作为免疫疗法。 在目标1中，我们将定义保护的免疫相关因素。我们的假设是，通过定义免疫 ，我们将更好地理解疫苗保护的机制和所需的免疫反应。 在人体试验中取得成功。我们将使用高通量生物传感器技术和我们广泛的gC2面板， GD2和gE2单抗确定三价疫苗是否产生至关重要的抗体 GC2、gD2和gE2的表位。感兴趣表位包括GC2上与补体成分结合的表位 C3b抑制补体激活，gE2结合Ig G Fc结构域以阻断Fc介导的活动，包括 补体激活和抗体依赖的细胞毒性，以及与病毒细胞受体结合的GD2 进入并调节细胞间的传播。我们将把与这些重要表位结合的抗体与 预防包括生殖器损伤和潜伏感染在内的临床后果。表位作图研究 将使我们能够评估每一种糖蛋白免疫原对保护的贡献。 目的利用mRNA免疫原研制生殖器疱疹治疗性疫苗。我们假设T细胞 对于一种成功的治疗性疫苗来说，反应将特别重要。在初步研究中，我们感染了 豚鼠阴道内感染HSV-2病毒，一旦康复，我们用糖蛋白E和I(gE2/GI2)免疫。 M RNA-LNP。GE2/GI2mRNA-LNP将生殖器复发病变的天数减少了47%，这是一个极好的 开始我们的主要终点&gt；减少70%的复发性生殖器病变。为了实现我们70%的目标， 我们将加入其他抗原，包括额外的糖蛋白、即刻早期、衣壳和被膜 免疫原并评估雄性和雌性小鼠的CD4和CD8 T细胞反应。我们将全力以赴 在豚鼠身上进行疗效研究的候选对象。我们首先将重点放在糖蛋白免疫原上，因为 针对一种密切相关的病毒水痘带状疱疹病毒的治疗性疫苗取得了显著成功，该疫苗使用 糖蛋白E作为抗原。我们将把GC2/GD2/gE2三价疫苗纳入治疗研究 确定一种疫苗配方是否对预防和治疗有效。如果成功，则 目标1和目标2中的研究将通过预防和治疗生殖器疱疹对数十亿人产生积极影响。

Abstract Genital herpes affects 650 million people globally. Vaccines are urgently needed to prevent infection and treat individuals already infected. During the current funding cycle, we developed a candidate vaccine for preventing genital herpes that uses nucleoside-modified mRNA encapsulated within lipid nanoparticles (LNP) to express herpes simplex virus type 2 (HSV-2) glycoproteins C, D, and E (gC2, gD2, gE2). The vaccine targets an entry molecule, gD2, and two immune evasion molecules, gC2 and gE2. Our vaccine candidate will enter phase 1 human trials in December 2022. Our new goals are to define the immune correlates of protection for the trivalent vaccine using sera we collected from immunized mice and guinea pigs during this grant cycle, and to develop an mRNA-based vaccine as immunotherapy. In Aim 1, we will define the immune correlates of protection. Our hypothesis is that by defining immune correlates, we will better understand the mechanisms of vaccine protection and the immune responses required for success in human trials. We will use high throughput biosensor technology and our extensive panel of gC2, gD2, and gE2 monoclonal antibodies to determine whether the trivalent vaccine produces antibodies to crucial epitopes on gC2, gD2 and gE2. The epitopes of interest include those on gC2 that bind complement component C3b to inhibit complement activation, gE2 that bind the IgG Fc domain to block Fc-mediated activities including complement activation and antibody-dependent cellular cytotoxicity, and gD2 that bind to cell receptors for virus entry and mediate cell-to-cell spread. We will correlate antibody binding to these important epitopes with protection against clinical outcomes including genital lesions and latent infection. The epitope mapping studies will enable us to assess the contribution of each of the glycoprotein immunogens to protection. Aim 2 uses mRNA immunogens to develop a genital herpes therapeutic vaccine. We hypothesize that T cell responses will be particularly important for a successful therapeutic vaccine. In Preliminary studies, we infected guinea pigs intravaginally with HSV-2 and once recovered, we immunized with glycoproteins E and I (gE2/gI2) mRNA-LNP. gE2/gI2 mRNA-LNP reduced the number of days with recurrent genital lesions by 47%, an excellent start towards our primary endpoint of >70% reduction in recurrent genital lesions. To achieve our goal of >70%, we will incorporate other antigens, including additional glycoproteins, immediate early, capsid and tegument immunogens and assess CD4 and CD8 T cell responses in male and female mice. We will advance the best candidates for efficacy studies in guinea pigs. We will focus initially on glycoprotein immunogens because of the remarkable success of a therapeutic vaccine for a closely related virus, varicella zoster virus, that uses glycoprotein E as the antigen. We will include the trivalent gC2/gD2/gE2 vaccine in the therapeutic studies to determine whether one vaccine formulation will be effective for prevention and treatment. If successful, the studies in Aims 1 and 2 will have a positive impact on billions of people by preventing and treating genital herpes.