Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Facultad de Medicina, UNT, Av. Kirchner 2100, (4000) San Miguel de Tucumán, Tucumán, Argentina.
Laboratorio de Ciencias Básicas. OR. Genética. Facultad de Medicina de la Universidad Nacional de Tucumán, Tucumán, Argentina.
Probiotics Antimicrob Proteins. 2020 Sep;12(3):961-972. doi: 10.1007/s12602-019-09598-7.
The hepatitis E virus (HEV) genotype 3 (GT3) is an emergent pathogen in industrialized countries. It is transmitted zoonotically and may lead to chronic hepatitis in immunocompromised individuals. We evaluated if the major antigen of HEV, the capsid protein, can be used in combination with immunobiotic bacterium-like particles (IBLP) for oral vaccination in a mouse model. We have cloned and expressed the RGS-His-tagged HEV GT3 capsid protein (ORF2) in E. coli and purified it by NiNTA. IBLP were obtained from two immunobiotic Lactobacillus rhamnosus strains acid- and heat-treated. ORF2 and the IBLP were orally administered to Balb/c mice. After three oral immunizations (14-day intervals), blood, intestinal fluid, Peyer´s patches, and spleen samples were drawn. IgA- and IgG-specific antibodies were determined by ELISA. Mononuclear cell populations from Peyer's patches and spleen were analyzed by flow cytometry, and the cytokine profiles were determined by ELISA to study cellular immunity. Orally administered recombinant ORF2 and IBLP from two L. rhamnosus strains (CRL1505 and IBL027) induced both antigen-specific humoral and cellular immune responses in mice. IBLP027 was more effective in inducing specific secretory IgA in the gut. IFN-γ, TNF-α, and IL-4 were produced by Peyer's plaques lymphocytes stimulated with ORF2 ex vivo suggesting a mixed Th1/Th2-type adaptive immune response in immunized mice. Oral vaccines are not invasive, do not need to be administered by specialized personal, and elicit both systemic and local immune responses at the port of entry. Here, we present an experimental oral vaccine for HEV GT3, which could be further developed for human and/or veterinary use.
戊型肝炎病毒（HEV）基因型 3（GT3）是工业化国家的一种新兴病原体。它通过动物传播，可能导致免疫功能低下个体的慢性肝炎。我们评估了 HEV 的主要抗原，衣壳蛋白，是否可以与免疫生物类似物细菌样颗粒（IBLP）结合，用于在小鼠模型中进行口服疫苗接种。我们已经在大肠杆菌中克隆并表达了 RGS-His 标记的 HEV GT3 衣壳蛋白（ORF2），并通过 NiNTA 进行了纯化。IBLP 是从两种免疫生物鼠李糖乳杆菌菌株经酸和热处理获得的。ORF2 和 IBLP 通过口服给予 Balb/c 小鼠。在进行了三次口服免疫（间隔 14 天）后，采集血液、肠液、派尔氏斑和脾脏样本。通过 ELISA 测定 IgA 和 IgG 特异性抗体。通过流式细胞术分析派尔氏斑和脾脏的单核细胞群，并通过 ELISA 测定细胞因子谱以研究细胞免疫。来自两种鼠李糖乳杆菌（CRL1505 和 IBL027）的口服重组 ORF2 和 IBLP 均可在小鼠中诱导抗原特异性体液和细胞免疫应答。IBL027 更有效地诱导肠道中特异性分泌型 IgA。体外刺激 ORF2 可使派尔氏斑淋巴细胞产生 IFN-γ、TNF-α 和 IL-4，表明免疫小鼠中存在混合的 Th1/Th2 型适应性免疫应答。口服疫苗无侵袭性，不需要由专业人员进行给药，并且可以在进入部位引发全身和局部免疫应答。在这里，我们提出了一种用于 HEV GT3 的实验性口服疫苗，该疫苗可以进一步开发用于人类和/或兽医用途。
