In situ vaccine application of inactivated CPMV nanoparticles for cancer immunotherapy.
In situ vaccine application of inactivated CPMV nanoparticles for cancer immunotherapy.
复制标题
DOI：
10.1039/d0ma00752h
复制
发表时间：
2021-03-07
影响因子：
5
通讯作者：
Steinmetz NF
中科院分区：
文献类型：
--
作者：
Chariou PL;Beiss V;Ma Y;Steinmetz NF
豇豆花叶病毒（CPMV）目前正在开发多种生物医学应用，包括癌症免疫治疗。特别地，CPMV作为原位疫苗的应用已经显示出前景;在这里，植物病毒纳米颗粒用作佐剂并直接注射到肿瘤中以逆转免疫抑制并引发全身性抗肿瘤免疫。这种基于CPMV的癌症免疫疗法的功效已在多种肿瘤小鼠模型和犬癌症患者中得到证实。然而，虽然CPMV对哺乳动物是非感染性的，但它对豆类是感染性的，因此，从安全性的角度来看，希望开发非感染性CPMV制剂。已经产生了缺乏核酸的CPMV的非感染性病毒样颗粒;然而，这种空CPMV纳米颗粒的功效与载有核酸的CPMV的功效不匹配。多价衣壳通过病原体模式识别受体（PRR）如toll样受体（TLR）激活先天免疫系统; RNA货物通过TLR-7/8提供额外的信号传导，这增强了这种佐剂的功效。因此，在这项研究中，我们着手开发RNA负载，但非感染性CPMV。我们报告了用紫外线灭活CPMV和用β-丙内酯（βPL）或福尔马林化学灭活。7.5 J cm−2 UV、50 mM βPL或1 mM福尔马林足以抑制CPMV并防止植物感染。我们使用RAW-Blue™报告细胞和鼠同基因、正交各向异性黑色素瘤模型（使用B16 F10细胞和C57 BL 6小鼠）在体外和体内比较了天然CPMV和灭活CPMV制剂的免疫原性。虽然体外测定表明甲醛和UV灭活的CPMV以与天然CPMV相当的水平激活了RAW-Blue™报告细胞; β PL灭活的CPMV似乎具有降低的活性。肿瘤小鼠模型实验表明化学灭活的CPMV（未测试UV处理的CPMV）的有效功效，导致肿瘤消退和存活增加;当与CPMV相比时，功效稍微降低，然而这些样品优于空的CPMV纳米颗粒。这些结果将促进安全和有效的基于CPMV的癌症免疫疗法的转化发展。豇豆花叶病毒（CPMV）目前正在开发多种生物医学应用，包括癌症免疫治疗。
Cowpea mosaic virus (CPMV) is currently in the development pipeline for multiple biomedical applications, including cancer immunotherapy. In particular the application of CPMV as in situ vaccine has shown promise; here the plant viral nanoparticle is used as an adjuvant and is injected directly into a tumor to reverse immunosuppression and prime systemic anti-tumor immunity. Efficacy of this CPMV-based cancer immunotherapy has been demonstrated in multiple tumor mouse models and canine cancer patients. However, while CPMV is non-infectious to mammals, it is infectious to legumes and therefore, from a safety perspective, it is desired to develop non-infectious CPMV formulations. Non-infectious virus-like particles of CPMV devoid of nucleic acids have been produced; nevertheless, efficacy of such empty CPMV nanoparticles does not match efficacy of nucleic acid-laden CPMV. The multivalent capsid activates the innate immune system through pathogen pattern recognition receptors (PRRs) such as toll-like receptors (TLRs); the RNA cargo provides additional signaling through TLR-7/8, which boosts the efficacy of this adjuvant. Therefore, in this study, we set out to develop RNA-laden, but non-infectious CPMV. We report inactivation of CPMV using UV light and chemical inactivation using β-propiolactone (βPL) or formalin. 7.5 J cm−2 UV, 50 mM βPL or 1 mM formalin was determined to be sufficient to inactivate CPMV and prevented plant infection. We compared the immunogenicity of native CPMV and inactivated CPMV formulations in vitro and in vivo using RAW-Blue™ reporter cells and a murine syngeneic, orthotropic melanoma model (using B16F10 cells and C57BL6 mice). While the in vitro assay indicated activation of the RAW-Blue™ reporter cells by formaldehyde and UV-inactivated CPMV at levels comparable to native CPMV; βPL-inactivated CPMV appeared to have diminished activity. Tumor mouse model experiments indicate potent efficacy of the chemically-inactivated CPMV (UV-treated CPMV was not tested) leading to tumor regression and increased survival; efficacy was somewhat reduced when compared to CPMV, however these samples outperformed the empty CPMV nanoparticles. These results will facilitate the translational development of safe and potent CPMV-based cancer immunotherapies. Cowpea mosaic virus (CPMV) is currently in the development pipeline for multiple biomedical applications, including cancer immunotherapy.