文献类型： 外文期刊

作者： Chu, Jun ¹ ; Guo, Yongxia ³ ; Xu, Guanlong ⁴ ; Zhang, Qiang ³ ; Zuo, Zonghui ³ ; Li, Qiang ³ ; Wang, Yihui ³ ; He, Cheng ¹ ;

作者机构： 1.Foshan Univ, Coll Life Sci & Engn, Foshan 528000, Guangdong, Peoples R China

2.Beijing Acad Agr & Forestry Serv, Inst Anim Husb & Vet Med, Beijing 100097, Peoples R China

3.China Agr Univ, Coll Vet Med, Key Lab Anim Epidemiol & Zoonosis, Minist Agr, Beijing 100193, Peoples R China

4.China Inst Vet Drug Control, Natl Reference Lab Anim Brucellosis, Beijing 100082, Peoples R China

关键词： Chlamydia psittaci; avian influenza virus H9N2; coinfection; macrophage functions; avian airsacculitis

期刊名称：ANIMALS （ 影响因子：2.752； 五年影响因子：2.942 ）

ISSN： 2076-2615

年卷期： 2020 年 10 卷 4 期

页码：

收录情况： SCI

摘要： Simple SummaryChlamydia psittaci, an obligate, intracellular, Gram-negative bacterium and economically relevant pathogen in poultry and pet bird, could cause psittacosis/ornithosis, and is also a human pathogen causing atypical pneumonia after zoonotic transmission. H9N2 influenza virus, a low pathogenic avian influenza viruses' subtype, has become endemic in different types of domestic poultry in lots of countries, resulting in great economic loss due to reduced egg production or high mortality associated with coinfection with other pathogens. These two pathogens are easily mixed with other pathogens to aggravate the disease, and often cause mixed infection in clinics. Co-infection of C. psittaci with H9N2 commonly induces severe pneumonia and high mortality in specific pathogen-free (SPF) chickens. According to previous studies, we postulated that C. psittaci infection may beneficial for the replication of H9N2 in HD11. Consequently, in this study, we clarify the pathogenic mechanism of coinfection with C. psittaci and H9N2 in the chicken macrophage cell line HD11, which is the first study of the coinfection of C. psittaci and H9N2 in vitro. Abstract In a pilot study, simultaneous infection with Chlamydia psittaci (C. psittaci) and H9N2 virus induced 20% mortality and severe avian airsacculitis, shedding light on animal models of poultry respiratory diseases. However, the pathogenesis is still unclear. In the current study, we hypothesized that C. psittaci infection execrates macrophage function and facilitates H9N2 infection. To explore the potential mechanism, we studied the effect of C. psittaci and H9N2 on the functions of HD11 cells in vitro by simultaneous infection of C. psittaci and H9N2. At the same time, we used infection with C. psittaci or H9N2 alone as the control groups. The results showed that coinfection with C. psittaci and H9N2 could significantly aggravate the mortality of HD11 cells compared to C. psittaci or H9N2 infection alone. In addition, coinfection with C. psittaci and H9N2 did not induce high C. psittaci loads compared to C. psittaci infection alone at 12- and 24-hours post-inoculation (hpi), but coinfection with C. psittaci and H9N2 could increase the loads of H9N2 compared to H9N2 alone in HD11 cells at 12 hpi. More importantly, inducible nitric oxide synthase (iNOS) expression levels, enzyme activity, nitric oxide (NO) production, and phagocytosis were reduced significantly in the group with C. psittaci and H9N2 coinfection compared to those of H9N2 or C. psittaci alone at 24 hpi. Finally, C. psittaci infection induced robust expressions of type Th2 cytokines interleukin (IL)-4 and IL-10, while interferon gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) displayed a significant decrease compared to H9N2 infection alone at 24 hpi. All the above data indicate that C. psittaci infection can facilitate H9N2 invasion and to aggravate severe avian airsacculitis by impairing macrophage functions.