Co-infection of Mycoplasma gallisepticum and Escherichia coli Triggers Inflammatory Injury Involving the IL-17 Signaling Pathway

Abstract

Mycoplasma gallisepticum and Escherichia coli are well known respiratory disease-inducing pathogens. Previous studies have reported that co-infection by MG and E.coli causes significant economic loss in the poultry industry. In order to assess the respiratory toxicity of co-infection in chicken lung, we established a co-infection model to investigate changes in the inflammatory cytokines, lung tissue structure, and transcriptome profiles of chicken lung. The results showed that co-infection caused a wider range of immune damage and more severe tissue lesions than single-pathogen infection. Differentially expressed gene (DEG) analysis indicated that 3,115/1,498/1,075 genes were significantly expressed among the three infection groups, respectively. Gene ontology and KEGG analysis showed genes enriched in response to immune response, cytokine-cytokine receptor interaction, and inflammation-related signaling pathways. Among these pathways, IL-17 signaling was found to be significantly enriched only in co-infection. The expression of IL-17C, CIKS, TRAF6, NFκB, C/EBPβ, and inflammatory chemokines were significantly up-regulated in response to co-infection. Taken together, we concluded that co-infection increased the expression of inflammatory chemokines in lungs through IL-17 signaling, leading to cilia loss and excessive mucus secretion. These results provide new insights into co-infection and reveal target proteins for drug therapy.

Arachidonic acid metabolism is elevated inMycoplasma gallisepticumandEscherichia colico-infection and induces LTC4 in serum as the biomarker for detecting poultry respiratory disease

“…The Co-infection group (B): 0.2 ml of MG medium (1 × 10 9 CCU/ml) was injected into the left caudal thoracic air sac at 7 th day, and 0.1 ml of E.coli bacteria (10 9 CFU/ml) was injected intraperitoneally at day 10 [ 25 ]. Four methods were used to verify whether the three models were successfully established including PCR tests, serological tests, pathological observations and pathogen isolation as previously described [ 21 , 26 ].…”

“…14/31 metabolites in the co-infection-specific metabolic signature mapped onto their interconnecting pathways and the involved genes were also added to the map. The expression of related genes was screened from our previous RNA-seq results by the BGI data mining online website ( http://report.bgi.com ) as explained in previously [ 21 ]. The results showed that the expression of LTC4 S and ALOX5AP in co-infection was elevated significantly compared to control group, while the expression of CYP2C21 L and LTA4 H were decreased significantly, and the other genes showed no significant differences.…”

“…NO was used to assess the underlying mechanisms of airway and lung inflammation for investigating asthma [ 20 ]. We previously demonstrated that co-infection of MG and E.coli triggers inflammatory injury involving IL-17 signaling pathway [ 21 ]. Furthermore, IL17A was reported that induce neutrophilic inflammation, airway hyperresponsiveness, steroid insensitivity and airway remodeling [ 22 ].…”

Mycoplasma gallisepticum Infection Impaired the Structural Integrity and Immune Function of Bursa of Fabricius in Chicken: Implication of Oxidative Stress and Apoptosis

“…A piece of bursal sample was processed for histopathological examination as described previously (21). In brief, samples were fixed in 10% formalin for 12 h, dehydrated in a series of ethanol solution, embedded in wax and cut into tiny sections for mounting on glass slides.…”

The design optimization of Chinese medicinal compound for the treatment of co-infection of Mycoplasma gallisepticum and Escherichia Coli

“…We have selected six TCMs according to this method, while the optimal combination of Chinese medicine is still an obstacle to the development of Chinese medicinal compound (CMC). In this study, we focus on the strategy for optimizing the combination of active components of CMC based on our laboratory's model research [7] .…”