涉及流感或新城疫病毒基质蛋白(M)的异源病毒样颗粒(VLP)组装已被广泛用于探索针对呼吸道合胞病毒(RSV)的VLP疫苗的功效。这里,我们试图通过在RSVM蛋白上表达融合前(pre-F)或糖蛋白(G)来产生同源RSVVLP,并评估其在小鼠中的保护功效。
■我们在节食夜蛾(Sf9)昆虫细胞中使用杆状病毒表达系统产生了VLP。表达RSVpre-F的重组杆状病毒,G,将M抗原接种到Sf9细胞中,粒子是自组装的。用表达前F或G的VLP免疫小鼠,和免疫参数进行评估以确定保护。
■我们的发现表明,通过利用与天然基质蛋白一起表达RSV前F或G蛋白的重组杆状病毒可以实现成功的VLP组装。用表达pre-F或G抗原的VLP免疫的小鼠引发稳健的血清介导的病毒中和。VLP免疫在小鼠血清中引起Th1偏向的RSV特异性抗体应答。在用RSVA2株攻击感染后,免疫小鼠经历了较少的嗜酸性粒细胞和IL-4在肺部的积累,尽管从CD4T细胞观察到TNF-α分泌的显着增加。有趣的是,脾抗体分泌细胞对RSVF抗原的反应显著增强,但在免疫和攻击感染后不针对RSVG抗原。用VLP免疫小鼠显着抑制肺组织病理学发展,如炎性免疫细胞流入和粘蛋白分泌减少所示。
■组合,这些疫苗诱导的免疫反应有助于成功抑制RSV在小鼠肺中的复制,并证明使用昆虫细胞来源的同源RSV基质蛋白组装RSVVLP是一种可行的方法。
UNASSIGNED: Heterologous virus-like particle (VLP) assembly involving influenza or the Newcastle disease virus matrix protein (M) has been extensively used to explore the efficacies of VLP vaccines against the respiratory syncytial virus (RSV). Here, we attempted to generate homologous RSV VLPs by expressing the pre-fusion (pre-F) or the glycoprotein (G) on the RSV M protein and evaluated their protective efficacy in mice.
UNASSIGNED: We generated VLPs using the baculovirus expression system in Spodoptera frugiperda (Sf9) insect cells. Recombinant baculoviruses expressing the RSV pre-F, G, and M antigens were inoculated into Sf9 cells, and particles were self-assembled. Mice were immunized with either pre-F or G-expressing VLPs, and immune parameters were assessed to determine protection.
UNASSIGNED: Our findings show that successful VLP assembly can be achieved by utilizing recombinant baculoviruses expressing the RSV pre-F or G proteins with the native matrix protein. Mice immunized with either pre-F or the G antigen-expressing VLPs elicited robust serum-mediated virus neutralization. VLP immunization evoked Th1-biased RSV-specific antibody responses in the sera of mice. Following challenge infection with the RSV A2 strain, immunized mice experienced lesser eosinophil and IL-4 accumulation in the lungs, though a substantial increase in TNF-α secretion was observed from CD4+ T cells. Interestingly, splenic antibody-secreting cell responses were substantially enhanced against RSV F antigen, but not against the RSV G antigen following immunization and challenge infection. Immunizing mice with the VLPs significantly inhibited pulmonary histopathology development, as indicated by the diminished inflammatory immune cell influx and mucin secretion.
UNASSIGNED: Combined, these vaccine-induced immune responses contributed to successfully inhibiting the RSV replication in the lungs of mice and demonstrated that RSV VLP assembly using insect cell-derived homologous RSV matrix protein is a feasible approach.