Klausberger Miriam, Tscheliessnig Rupert, Neff Silke, Nachbagauer Raffael, Wohlbold Teddy John, Wilde Monika, Palmberger Dieter, Krammer Florian, Jungbauer Alois, Grabherr Reingard
Department of Biotechnology, University of Natural Resources and Life Sciences Vienna, Vienna, Austria.
Austrian Centre of Industrial Biotechnology, Vienna, Austria.
PLoS One. 2016 Apr 18;11(4):e0153579. doi: 10.1371/journal.pone.0153579. eCollection 2016.
Significant genetic variability in the head region of the influenza A hemagglutinin, the main target of current vaccines, makes it challenging to develop a long-lived seasonal influenza prophylaxis. Vaccines based on the conserved hemagglutinin stalk domain might provide broader cross-reactive immunity. However, this region of the hemagglutinin is immunosubdominant to the head region. Peptide-based vaccines have gained much interest as they allow the immune system to focus on relevant but less immunogenic epitopes. We developed a novel influenza A hemagglutinin-based display platform for H1 hemagglutinin stalk peptides that we identified in an epitope mapping assay using human immune sera and synthetic HA peptides. Flow cytometry and competition assays suggest that the identified stalk sequences do not recapitulate the epitopes of already described broadly neutralizing stalk antibodies. Vaccine constructs displaying 25-mer stalk sequences provided up to 75% protection from lethal heterologous virus challenge in BALB/c mice and induced antibody responses against the H1 hemagglutinin. The developed platform based on a vaccine antigen has the potential to be either used as stand-alone or as prime-vaccine in combination with conventional seasonal or pandemic vaccines for the amplification of stalk-based cross-reactive immunity in humans or as platform to evaluate the relevance of viral peptides/epitopes for protection against influenza virus infection.
甲型流感血凝素头部区域存在显著的基因变异性，而该区域是当前疫苗的主要靶点，这使得开发长效季节性流感预防措施具有挑战性。基于保守的血凝素茎部结构域的疫苗可能会提供更广泛的交叉反应性免疫。然而，血凝素的这一区域在免疫方面相对于头部区域来说是次要的。基于肽的疫苗备受关注，因为它们能让免疫系统聚焦于相关但免疫原性较低的表位。我们开发了一种新型的基于甲型流感血凝素的展示平台，用于展示我们在使用人免疫血清和合成HA肽的表位作图分析中鉴定出的H1血凝素茎部肽段。流式细胞术和竞争试验表明，所鉴定的茎部序列并未重现已描述的广泛中和茎部抗体的表位。展示25聚体茎部序列的疫苗构建体在BALB/c小鼠中提供了高达75%的针对致死性异源病毒攻击的保护，并诱导了针对H1血凝素的抗体反应。所开发的基于疫苗抗原的平台有可能单独使用，或作为初免疫苗与传统季节性或大流行疫苗联合使用，以增强人类基于茎部的交叉反应性免疫，或作为评估病毒肽/表位对预防流感病毒感染相关性的平台。
