Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.
The Pirbright Institute, Pirbright, Surrey, UK.
Sci Rep. 2018 Jan 16;8(1):853. doi: 10.1038/s41598-017-19079-y.
Cattle are subject to economically-important respiratory tract infections by various bacterial and viral pathogens and there is an urgent need for the development of more realistic in vitro models of the bovine respiratory tract to improve our knowledge of disease pathogenesis. In the present study, we have optimized the culture conditions in serum-free medium that allow bovine bronchial epithelial cells (BBECs) grown at an air-liquid interface to differentiate into a three-dimensional epithelium that is highly representative of the bovine airway. Epidermal growth factor was required to trigger both proliferation and differentiation of BBECs whilst retinoic acid was also essential for mucociliary differentiation. Triiodothyronine was demonstrated not to be important for the differentiation of BBECs. Oxygen concentration had a minimal effect although optimal ciliation was achieved when BBECs were cultured at 14% oxygen tension. Insert pore-density had a significant effect on the growth and differentiation of BBECs; a high-pore-density was required to trigger optimum differentiation. The established BBEC model will have wide-ranging applications for the study of bacterial and viral infections of the bovine respiratory tract; it will contribute to the development of improved vaccines and therapeutics and will reduce the use of cattle in in vivo experimentation.
牛易患各种细菌性和病毒性呼吸道传染病，因此迫切需要开发更逼真的牛呼吸道体外模型，以增进我们对疾病发病机制的了解。在本研究中，我们优化了无血清培养基中的培养条件，使在气-液界面生长的牛支气管上皮细胞（BBEC）分化为高度代表牛气道的三维上皮细胞。表皮生长因子（EGF）不仅能触发 BBEC 的增殖，还能触发其分化，而维甲酸（RA）对于黏液纤毛分化也是必需的。三碘甲状腺原氨酸（T3）对 BBEC 的分化并不重要。尽管 BBEC 在 14%氧张力下培养时能达到最佳纤毛化，但氧浓度的影响很小。插板孔密度对 BBEC 的生长和分化有显著影响；高孔密度可触发最佳分化。所建立的 BBEC 模型将广泛应用于牛呼吸道的细菌和病毒感染研究；它将有助于开发改进的疫苗和疗法，并减少在体内实验中使用牛。
