Yamamoto Satomi, Okumura Shiori, Kobayashi Risa, Maeda Yosuke, Takahashi Fumiaki, Tanabe Taishi
Laboratory of Veterinary Microbiology, School of Veterinary Medicine, Kitasato University, Aomori, Japan.
Laboratory of Clinical Veterinary Medicine for Large Animal, School of Veterinary Medicine, Kitasato University, Aomori, Japan.
J Vet Med Sci. 2024 Oct 1;86(10):1068-1075. doi: 10.1292/jvms.24-0068. Epub 2024 Aug 8.
In cattle, bovine respiratory syncytial virus (BRSV) is associated with secondary bacterial infections; however, the mechanisms of the interaction between BRSV and bacteria are unclear. Trueperella pyogenes (T. pyogenes) causes pneumonia in cattle and is involved in secondary infections following viral infections. In this study, we evaluated the effect of BRSV infection on the adhesion of T. pyogenes to BRSV-infected cells. BRSV infection significantly enhanced the adhesion of T. pyogenes to cells in a multiplicity of infection- and time-dependent manner. The BRSV-mediated change in the adhesion of T. pyogenes was widely observed in various cell types and bacterial strains. The results from the gentamicin protection assay showed that BRSV infection did not affect the intracellular invasion ability of T. pyogenes. Furthermore, adhesion assays conducted using BRSV G protein-expressing cells and anti-BRSV G antibodies revealed that the increased adhesion of T. pyogenes to cells was mediated by the G protein of BRSV. In addition, immunofluorescence assay revealed the colocalization of BRSV G protein and T. pyogenes. Thus, BRSV infection can potentially lead to bovine respiratory disease complex by promoting the adhesion of T. pyogenes to the infected cells.
在牛中，牛呼吸道合胞病毒（BRSV）与继发性细菌感染有关；然而，BRSV与细菌之间相互作用的机制尚不清楚。化脓隐秘杆菌（T. pyogenes）可导致牛患肺炎，并参与病毒感染后的继发性感染。在本研究中，我们评估了BRSV感染对化脓隐秘杆菌黏附于BRSV感染细胞的影响。BRSV感染以感染复数和时间依赖性方式显著增强了化脓隐秘杆菌对细胞的黏附。在各种细胞类型和细菌菌株中广泛观察到BRSV介导的化脓隐秘杆菌黏附变化。庆大霉素保护试验结果表明，BRSV感染不影响化脓隐秘杆菌的细胞内侵袭能力。此外，使用表达BRSV G蛋白的细胞和抗BRSV G抗体进行的黏附试验表明，化脓隐秘杆菌对细胞黏附增加是由BRSV的G蛋白介导的。此外，免疫荧光试验揭示了BRSV G蛋白与化脓隐秘杆菌的共定位。因此，BRSV感染可能通过促进化脓隐秘杆菌黏附于感染细胞而导致牛呼吸道疾病综合征。
