Mei Chen, Sun Ai-Hua, Blackall Patrick J, Xian Hong, Li Shu-Fang, Gong Yu-Mei, Wang Hong-Jun
Beijing Key Laboratory for Prevention and Control of Infectious Diseases in Livestock and Poultry, Institute of Animal Husbandry and Veterinary Medicine, Beijing Municipal Academy of Agriculture and Forestry, Beijing, China.
Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD, Australia.
Front Microbiol. 2020 Sep 25;11:518060. doi: 10.3389/fmicb.2020.518060. eCollection 2020.
, the causative agent of infectious coryza, is known to release outer membrane vesicles (OMVs). In the present study, we investigated the composition, bioactivities, and functional properties of the OMVs of . Following extraction and purification, the OMVs were observed to be spherical in shape, with diameters ranging from 20 to 300 nm. The vesicles contained endotoxin as well as genomic DNA. The molecular weights of the OMV-contained protein fragments were mostly concentrated at 65 and 15 kDa. The components of the OMV proteins were mainly various functional enzymes (e.g., ATP-dependent RNA helicase), structural components (e.g., streptomycin B receptor and membrane protein), and some hypothetical proteins with unknown functions. The expression levels of inflammation-related factors, such as interleukin (IL)-2, IL-6, IL-1β, IL-10, and inducible nitric oxide synthase (iNOs), were significantly upregulated in chicken macrophage cells HD11 incubated with OMVs. Serum IgG antibodies were measured after two intramuscular injections of an OMV-based vaccine into specific pathogen-free (SPF) chickens. The vaccinated chickens were then challenged by of homologous and heterologous serovars. It was noted that the vaccinated chickens produced immunoglobulin G (IgG) antibodies against . The OMVs conferred an acceptable level of protection (70%), defined as an absence of colonization and of clinical signs, against the homologous strain (serovar A), while the cross-protection against heterologous challenge with serovars B and C was much weaker. However, the OMVS did provide significant protection against clinical signs for all three serovars. Overall, this study laid a foundation for further unraveling the functional roles of OMVs released by .
传染性鼻炎的病原体已知会释放外膜囊泡（OMVs）。在本研究中，我们调查了[病原体名称]的OMVs的组成、生物活性和功能特性。提取和纯化后，观察到OMVs呈球形，直径范围为20至300纳米。这些囊泡含有内毒素以及基因组DNA。OMV所含蛋白质片段的分子量大多集中在65 kDa和15 kDa。OMV蛋白质的成分主要是各种功能酶（如ATP依赖性RNA解旋酶）、结构成分（如链霉素B受体和膜蛋白）以及一些功能未知的假定蛋白质。在用OMVs孵育的鸡巨噬细胞HD11中，炎症相关因子如白细胞介素（IL）-2、IL-6、IL-1β、IL-10和诱导型一氧化氮合酶（iNOs）的表达水平显著上调。在对无特定病原体（SPF）鸡进行两次肌肉注射基于OMV的疫苗后，测量血清IgG抗体。然后用同源和异源血清型的[病原体名称]对接种疫苗的鸡进行攻毒。注意到接种疫苗的鸡产生了针对[病原体名称]的免疫球蛋白G（IgG）抗体。OMVs对同源菌株（血清型A）提供了可接受水平的保护（70%），定义为无定植和无临床症状，而对血清型B和C的异源攻毒的交叉保护则弱得多。然而，OMVs确实为所有三种血清型的临床症状提供了显著保护。总体而言，本研究为进一步阐明[病原体名称]释放的OMVs的功能作用奠定了基础。
