González-Miró Majela, Radecker Anna-Maria, Rodríguez-Noda Laura M, Fariñas-Medina Mildrey, Zayas-Vignier Caridad, Hernández-Cedeño Mabel, Serrano Yohana, Cardoso Félix, Santana-Mederos Darielys, García-Rivera Dagmar, Valdés-Balbín Yury, Vérez-Bencomo Vicente, Rehm Bernd H A
Finlay Vaccine Institute, 27th Avenue, No. 19805 between 198 and 202, La Lisa, Havana 11600, Cuba.
Institute of Fundamental Sciences, Massey University, Colombo Road, Palmerston North 4422, New Zealand.
ACS Biomater Sci Eng. 2018 Sep 10;4(9):3413-3424. doi: 10.1021/acsbiomaterials.8b00579. Epub 2018 Aug 14.
can cause life-threatening infections mostly in infants, children, and elderly people. Capsular polysaccharide conjugate vaccines provide serotype-dependent protection against infections but fail to protect against new emerging serotypes. To overcome these limitations, pneumolysin (Ply), a serotype-independent and conserved protein was selected. As such subunit vaccines lack immunogenicity, we engineered Ply to be attached to self-assembled polyester beads in order to boost immunogenicity. To display Ply at the surface of these polyester beads, it was translationally fused to the N-terminus of the polyhydroxybutyrate (PHB) synthase (PhaC), which mediates PHB bead assembly inside recombinant . We also chemically conjugated the capsular polysaccharide (CPS) 19F to isolated PHB beads to further assess their antigen carrier properties. CPS conjugated to soluble tetanus toxoid served as control. Balb/c mice immunized with Ply-PhaC beads and 19F-PhaC beads induced specific and higher IgG levels than the respective soluble counterparts. The induced IgG antibodies recognized Ply in whole cell lysates of six different serotypes of Additionally, restimulated splenocytes from animals immunized with Ply-PhaC beads produced a balanced INF-γ/IL-17A profile unlike animals immunized with soluble Ply. The 19F-PhaC beads induced production of antibodies showing high opsonophagocytic titers against the homologous strain, serotype 19F, while CPS 19F only mixed with PhaC beads did not elicit any detectable immune response. This study provided insight into the design of PHB beads as a carrier of proteinaceous antigens and CPS in order to induce immune responses for the prevention of pneumococcal infections.
主要可在婴儿、儿童和老年人中引发危及生命的感染。荚膜多糖结合疫苗可提供针对特定血清型感染的保护，但无法抵御新出现的血清型。为克服这些局限性，我们选择了肺炎溶素（Ply），一种血清型非依赖性且保守的蛋白质。由于此类亚单位疫苗缺乏免疫原性，我们对Ply进行改造，使其附着于自组装聚酯珠上，以增强免疫原性。为使Ply展示在这些聚酯珠表面，将其与聚羟基丁酸酯（PHB）合酶（PhaC）的N端进行翻译融合，PhaC可介导重组菌体内PHB珠的组装。我们还将荚膜多糖（CPS）19F化学偶联至分离出的PHB珠上，以进一步评估其抗原载体特性。偶联至可溶性破伤风类毒素的CPS用作对照。用Ply-PhaC珠和19F-PhaC珠免疫的Balb/c小鼠诱导产生的特异性IgG水平高于各自的可溶性对应物。诱导产生的IgG抗体可识别六种不同血清型肺炎链球菌全细胞裂解物中的Ply。此外，用Ply-PhaC珠免疫的动物经再刺激的脾细胞产生的INF-γ/IL-17A谱较为平衡，这与用可溶性Ply免疫的动物不同。19F-PhaC珠诱导产生的抗体对同源菌株血清型19F显示出高调理吞噬效价，而仅将CPS 19F与PhaC珠混合则未引发任何可检测到的免疫反应。本研究为将PHB珠设计为蛋白质抗原和CPS的载体以诱导免疫反应预防肺炎球菌感染提供了见解。
