title: Prominent contribution of Th1, Th17, and Tregs to the host response during M. neoaurum infection.
abstract: Nontuberculous mycobacteria are ubiquitous in outside environment and animals. As for nontuberculous mycobacteria infection, there is only limited information in humans regarding infection and the subsequent immune response, especially for Mycobacterium neoaurum. Here, haematoxylin-eosin and Ziehl-Neelsen staining were used to observe pathological changes and detect acid-fast bacilli in organ samples in mouse model. Flow cytometry and quantitative real-time polymerase chain reaction were performed to analyze the contribution of Th1, Th17 and Tregs to the host immune response. M. neoaurum caused chronic infection in mice, resulting in infiltrates with large aggregates of inflammatory cells, especially macrophages, in lung tissues. Our results indicated that 72% of CD4+ T cells appeared in the early days of infection, which was followed by a decrease to 47% by day 32, and then a rise to 76% by day 56. Moreover, we found higher frequency of IFN-g-producing CD4+ T cells and elevated mRNA expression of the transcription factor T-bet in the lungs; however, we observed lower mRNA expression of the transcription factor RORgt and lower frequency of IL-17-producing CD4+ T cells. A transient relative decrease in the number of Treg cells was observed in the lungs; however, the number of Tregs did not change significantly between the first and last day following infection. Thus, M. neoaurum causes chronic infection in C57BL/6 mice, with Th1, Th17, and Tregs playing a prominent role in the host response. The present study may lay the basis for further studies on the mechanisms underlying infection with nontuberculous mycobacteria.
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, China wangchunfeng@jlau.edu.cn.
authors.forename: C F
authors.initials: CF
authors.lastname: Wang
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, China.
authors.forename: W T
authors.initials: WT
authors.lastname: Yang
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, China.
authors.forename: L M
authors.initials: LM
authors.lastname: Yue
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, China.
authors.forename: J Y
authors.initials: JY
authors.lastname: Qiu
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, China.
authors.forename: L J
authors.initials: LJ
authors.lastname: Zhang
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, China.|Key Laboratory of Animal Production, Product Quality and Security Ministry of Education, Changchun, China.
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.affiliation: College of Life Sciences, Jilin Agricultural University, Changchun, China.
authors.forename: X Y
authors.initials: XY
authors.lastname: Jiang
authors.affiliation: College of Animal Science and Technology, Jilin Agricultural University, Changchun, China.|Key Laboratory of Animal Production, Product Quality and Security Ministry of Education, Changchun, China.
authors.forename: A D
authors.initials: AD
authors.lastname: Qian
mesh_terms: D056704:Adaptive Immunity; D000818:Animals; D058491:Bacterial Load / Q000276:immunology; D015169:Colony Count, Microbial; D005260:Female; D051858:Forkhead Transcription Factors / Q000378:metabolism; D005786:Gene Expression Regulation; D054884:Host-Pathogen Interactions / Q000276:immunology*; D008168:Lung / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D016131:Lymphocyte Subsets / Q000276:immunology; D008810:Mice, Inbred C57BL; D009161:Mycobacterium / Q000254:growth & development / Q000276:immunology*; D009164:Mycobacterium Infections / Q000276:immunology* / Q000382:microbiology* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology*; D058504:Th17 Cells / Q000276:immunology*
chemical_list: D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D012333:RNA, Messenger