Farooq Umar, Liu Guiqiong, Ahmed Sohail, Yang Huiguo, Ahmed Mehboob, Jiang Xunping
Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan, China.
Laboratory of Small Ruminant Genetics, Breeding and Reproduction, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, China.
Front Immunol. 2025 Jul 18;16:1598969. doi: 10.3389/fimmu.2025.1598969. eCollection 2025.
The Orf virus (ORFV) poses a significant threat to livestock and human health, causing economic losses in the livestock industry and potential zoonotic infections. Given the limitations of current vaccines, the objective of this study was to investigate the immune response and gut microbiota modulation induced by the ORFV B2L gene-based DNA vaccine (GV) and the live attenuated vaccine (LV) in rats. The findings of this study will provide a scientific foundation for the development of more effective vaccines. Female Sprague-Dawley rats, which were free of specific pathogens, were divided into three groups. The experiment included three groups: the first group was designated as the GV group, the second group was designated as the LV group, and the third group was designated as the control group. Rats in the GV group received intra-muscular injection of 100μg/dose of pVAX - B2L - asd plasmid, those in the LV group were immunized with a commercial live - attenuated vaccine, and the control group was injected with PBS. After immunization, various immune - related parameters, such as T - cell subsets, antibody levels, cytokines, and oxidative stress markers, were measured. To this end, composition and function of gut microbiota were thoroughly examined through the implementation of 16S rRNA gene sequencing and PICRUSt-2 functional prediction. The GV group exhibited elevated levels of cellular and humoral immunity. It had a higher percentage of CD4 and CD8 T cells, enhanced levels of cytokines i.e. IL - 2, IL - 6, and TNF - α, elevated IgA, IgG antibody production compared to the LV and control groups. Additionally, the GV group showed reduced oxidative stress. In terms of gut microbiota, GV immunization led to an increase in beneficial bacteria like Lachnospi-raceae_NK4A136_group and a decrease in harmful or potentially pathogenic bacteria. KEGG pathway analysis indicated that differential flora exhibited an increase in metabolic pathway diversity, including those related to biological systems, metabolism, and human diseases. In sum, the results of the present study demonstrate that the ORFV B2L DNA vaccine (GV) elicited a more robust immune response and exerted a beneficial effect on composition and function of the gut microbiota compared with ORF live-attenuated vaccine. The results of the present study indicate that modulation of gut microbiota by GV vaccine play a crucial role in enhancing vaccine efficacy. The current study provides new perspectives on ORFV vaccine development and its association with vaccines and gut microbiota modulation.
羊口疮病毒（ORFV）对家畜和人类健康构成重大威胁，给畜牧业造成经济损失，并可能引发人畜共患病感染。鉴于目前疫苗存在局限性，本研究旨在探究基于ORFV B2L基因的DNA疫苗（GV）和减毒活疫苗（LV）在大鼠体内诱导的免疫反应及对肠道微生物群的调节作用。本研究结果将为开发更有效的疫苗提供科学依据。将无特定病原体的雌性斯普拉格-道利大鼠分为三组。实验包括三组：第一组为GV组，第二组为LV组，第三组为对照组。GV组大鼠肌肉注射100μg/剂量的pVAX - B2L - asd质粒，LV组大鼠用市售减毒活疫苗免疫，对照组注射PBS。免疫后，检测各种免疫相关参数，如T细胞亚群、抗体水平、细胞因子和氧化应激标志物。为此，通过实施16S rRNA基因测序和PICRUSt-2功能预测，全面检查肠道微生物群的组成和功能。GV组细胞免疫和体液免疫水平升高。与LV组和对照组相比，其CD4和CD8 T细胞百分比更高，细胞因子IL - 2、IL - 6和TNF - α水平升高，IgA、IgG抗体产生增加。此外，GV组氧化应激降低。在肠道微生物群方面，GV免疫导致有益菌如毛螺菌科_NK4A136_组增加，有害或潜在致病菌减少。KEGG通路分析表明，差异菌群的代谢通路多样性增加，包括与生物系统、代谢和人类疾病相关的通路。总之，本研究结果表明，与ORF减毒活疫苗相比，ORFV B2L DNA疫苗（GV）引发了更强的免疫反应，并对肠道微生物群的组成和功能产生了有益影响。本研究结果表明，GV疫苗对肠道微生物群的调节在提高疫苗效力方面起着关键作用。本研究为ORFV疫苗开发及其与疫苗和肠道微生物群调节的关联提供了新的视角。
