Staphylococcus aureus and Escherichia coli elicit different innate immune responses from bovine mammary epithelial cells |
| |
| Authors: | Yunhe Fu Ershun Zhou Zhicheng Liu Fenyang Li Dejie Liang Bo Liu Xiaojing Song Fuyi Zhao Xiaosheng Fen Depeng Li Yongguo Cao Xichen Zhang Naisheng Zhang Zhengtao Yang |
| |
| Institution: | 1. Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province 130062, People''s Republic of China;2. Guangdong Institute of Modern Agricultural Group, Guangzhou, Guangdong Province, People''s Republic of China |
| |
| Abstract: | Escherichia coli and Staphylococcus aureus are the most important pathogenic bacteria causing bovine clinical mastitis and subclinical mastitis, respectively. However, little is known about the molecular mechanisms underlying the different host response patterns caused by these bacteria. The aim of this study was to characterize the different innate immune responses of bovine mammary epithelium cells (MECs) to heat-inactivated E. coli and S. aureus. Gene expression of Toll-like receptor 2 (TLR2) and TLR4 was compared. The activation of nuclear factor kappa B (NF-κB) and the kinetics and levels of cytokine production were analyzed. The results show that the mRNA for TLR2 and TLR4 was up-regulated when the bovine MECs were stimulated with heat-inactivated E. coli, while only TLR2 mRNA was up-regulated when the bovine MECs were stimulated with heat-inactivated S. aureus. The expression of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 and IL-8 increased more rapidly and higher when the bovine MECs were stimulated with heat-inactivated E. coli than when they were stimulated with heat-inactivated S. aureus. E. coli strongly activated NF-κB in the bovine MECs, while S. aureus failed to activate NF-κB. Heat-inactivated S. aureus could induce NF-κB activation when bovine MECs cultured in medium without fetal calf serum. These results were confirmed using TLR2- and TLR4/MD2-transfected HEK293 cells and suggested that differential TLR recognition and the lack of NF-κB activation account for the impaired immune response elicited by heat-inactivated S. aureus. |
| |
| Keywords: | Escherichia coli Staphylococcus aureus Bovine mammary epithelial cells TLR4 TLR2 NF-κB |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
