Wang Yang, Gong Shenglong, Dong Xiao, Li Jinpeng, Grenier Daniel, Yi Li
College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China.
Key Laboratory of Molecular Pathogen and Immunology of Animal of Luoyang, Luoyang, China.
Front Microbiol. 2020 Apr 7;11:507. doi: 10.3389/fmicb.2020.00507. eCollection 2020.
() and () are primary swine pathogens that have been frequently co-isolated from pigs suffering from severe respiratory disease. The purpose of this study was to investigate the biological impacts of the interactions between and . A single- and dual-species culture model was established via HA9801 (serotype 2) and CVCC265 (serotype 1). The single or mixed biofilms were imaged by confocal laser scanning microscopy. The biomass and viable cells in biofilms were quantified by crystal violet staining and determination of colony-forming units. The antibiotic susceptibility was determined by a microdilution broth method. The differences in gene transcription in pure- or mixed-species biofilms of and was evaluated by quantitative PCR. and formed two-species biofilms when co-cultured . When co-cultured with , biofilm formation by was significantly increased with the absence of NAD that is necessary for the growth of . Moreover, compared with monocultures, the antibiotic resistance of and was both enhanced in the co-culture model. When grown in dual-species biofilms, for , genes associated with virulence factors, including exotoxins and adhesins, were significantly upregulated. For , virulence factor-related genes , , , and were highly induced. These results suggest that the interspecies interactions between and may be cooperative under specific conditions and may play an important role in the disease progression and persistent infection.
（）和（）是主要的猪病原体，经常从患有严重呼吸道疾病的猪中共同分离出来。本研究的目的是调查（）和（）之间相互作用的生物学影响。通过HA9801（2型血清型）和CVCC265（1型血清型）建立了单物种和双物种培养模型。通过共聚焦激光扫描显微镜对单物种或混合生物膜进行成像。通过结晶紫染色和菌落形成单位的测定对生物膜中的生物量和活细胞进行定量。通过微量稀释肉汤法测定抗生素敏感性。通过定量PCR评估（）和（）的纯物种或混合物种生物膜中基因转录的差异。（）和（）共培养时形成双物种生物膜。与（）共培养时，在缺乏（）生长所必需的NAD的情况下，（）的生物膜形成显著增加。此外，与单培养相比，在共培养模型中（）和（）的抗生素抗性均增强。当在双物种生物膜中生长时，对于（），与毒力因子相关的基因，包括外毒素和粘附素，显著上调。对于（），毒力因子相关基因（）、（）、（）和（）被高度诱导。这些结果表明，（）和（）之间的种间相互作用在特定条件下可能是协同的，并且可能在疾病进展和持续感染中起重要作用。
