Abstract：
Antigen presenting cells (APCs)-derived exosomes are nano-vesicles that can induce antigen-specific T cell responses, and possess therapeutic effects in clinical settings. Moreover, dendritic cells (DCs)-based vaccines have been developed to combat human immunodeficiency virus-1 (HIV-1) infection in preclinical and clinical trials. We investigated the immunostimulatory effects (B- and T-cells activities) of DCs- and exosomes-based vaccine constructs harboring HIV-1 Nefmut-Tat fusion protein as an antigen candidate and heat shock protein 70 (Hsp70) as an adjuvant in mice. The modified DCs and engineered exosomes harboring Nefmut-Tat protein or Hsp70 were prepared using lentiviral vectors compared to electroporation, characterized and evaluated by in vitro and in vivo immunological tests. Our data indicated that the engineered exosomes induced high levels of total IgG, IgG2a, IFN-γ, TNF-α and Granzyme B. Moreover, co-injection of exosomes harboring Hsp70 could significantly increase the secretion of antibodies, cytokines and Granzyme B. The highest levels of IFN-γ and TNF-α were observed in exosomes harboring Nefmut-Tat combined with exosomes harboring Hsp70 (Exo-Nefmut-Tat + Exo-Hsp70) regimen after single-cycle replicable (SCR) HIV-1 exposure. Generally, Exo-Nefmut-Tat + Exo-Hsp70 regimen can be considered as a promising safe vaccine candidate due to high T-cells (Th1 and CTL) activity and its maintenance against SCR HIV-1 exposure.
摘要：
抗原呈递细胞（APC）来源的外泌体是可以诱导抗原特异性T细胞反应的纳米囊泡，并在临床环境中具有治疗作用。此外，在临床前和临床试验中，已经开发了基于树突状细胞（DC）的疫苗来对抗人类免疫缺陷病毒1（HIV-1）感染。我们研究了含有HIV-1Nefmut-Tat融合蛋白作为抗原候选物和热休克蛋白70（Hsp70）作为佐剂的基于DC和外泌体的疫苗构建体的免疫刺激作用（B和T细胞活性）小鼠。与电穿孔相比，使用慢病毒载体制备修饰的DC和带有Nefmut-Tat蛋白或Hsp70的工程外泌体，通过体外和体内免疫学测试进行表征和评估。我们的数据表明，工程外泌体诱导高水平的总IgG，IgG2a,IFN-γ，TNF-α和颗粒酶B。共同注射携带Hsp70的外泌体可以显着增加抗体的分泌，在单周期可复制（SCR）HIV-1暴露后，在含有Nefmut-Tat的外泌体和含有Hsp70（Exo-Nefmut-Tat+Exo-Hsp70）方案的外泌体中观察到最高水平的IFN-γ和TNF-α。一般来说,Exo-Nefmut-Tat+Exo-Hsp70方案由于高T细胞(Th1和CTL)活性及其对SCRHIV-1暴露的维持而被认为是一种有前途的安全疫苗候选方案。
