scholarly journals Development of anEx VivoTissue Platform To Study the Human Lung Response to Coxiella burnetii

2016 ◽  
Vol 84 (5) ◽  
pp. 1438-1445 ◽  
Author(s):  
Joseph G. Graham ◽  
Caylin G. Winchell ◽  
Richard C. Kurten ◽  
Daniel E. Voth

Coxiella burnetiiis an intracellular bacterial pathogen that causes human Q fever, an acute debilitating flu-like illness that can also present as chronic endocarditis. Disease typically occurs following inhalation of contaminated aerosols, resulting in an initial pulmonary infection. In human cells,C. burnetiigenerates a replication niche termed the parasitophorous vacuole (PV) by directing fusion with autophagosomes and lysosomes.C. burnetiirequires this lysosomal environment for replication and uses a Dot/Icm type IV secretion system to generate the large PV. However, we do not understand howC. burnetiievades the intracellular immune surveillance that triggers an inflammatory response. We recently characterized human alveolar macrophage (hAM) infectionin vitroand found that avirulentC. burnetiitriggers sustained interleukin-1β (IL-1β) production. Here, we evaluated infection ofex vivohuman lung tissue, defining a valuable approach for characterizingC. burnetiiinteractions with a human host. Within whole lung tissue,C. burnetiipreferentially replicated in hAMs. Additionally, IL-1β production correlated with formation of an apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC)-dependent inflammasome in response to infection. We also assessed potential activation of a human-specific noncanonical inflammasome and found that caspase-4 and caspase-5 are processed during infection. Interestingly, although inflammasome activation is closely linked to pyroptosis, lytic cell death did not occur followingC. burnetii-triggered inflammasome activation, indicating an atypical response after intracellular detection. Together, these studies provide a novel platform for studying the human innate immune response toC. burnetii.

2019 ◽  
Vol 87 (5) ◽  
Author(s):  
Amanda L. Dragan ◽  
Richard C. Kurten ◽  
Daniel E. Voth

ABSTRACTHuman Q fever is caused by the intracellular bacterial pathogenCoxiella burnetii. Q fever presents with acute flu-like and pulmonary symptoms or can progress to chronic, severe endocarditis. After human inhalation,C. burnetiiis engulfed by alveolar macrophages and transits through the phagolysosomal maturation pathway, resisting the acidic pH of lysosomes to form a parasitophorous vacuole (PV) in which to replicate. Previous studies showed thatC. burnetiireplicates efficiently in primary human alveolar macrophages (hAMs) inex vivohuman lung tissue. AlthoughC. burnetiireplicates in most cell typesin vitro, the pathogen does not grow in non-hAM cells of human lung tissue. In this study, we investigated the interaction betweenC. burnetiiand other pulmonary cell types apart from the lung environment.C. burnetiiformed a prototypical PV and replicated efficiently in human pulmonary fibroblasts and in airway, but not alveolar, epithelial cells. Atypical PV expansion in alveolar epithelial cells was attributed in part to defective recruitment of autophagy-related proteins. Further assessment of theC. burnetiigrowth niche showed that macrophages mounted a robust interleukin 8 (IL-8), neutrophil-attracting response toC. burnetiiand ultimately shifted to an M2-polarized phenotype characteristic of anti-inflammatory macrophages. Considering our findings together, this study provides further clarity on the uniqueC. burnetii-lung dynamic during early stages of human acute Q fever.


2020 ◽  
Vol 2 (7A) ◽  
Author(s):  
VerÓnica Ferrando ◽  
Yvonne Börgeling ◽  
Alexander Mellmann ◽  
Shrey Gandhi ◽  
Linda Brunotte ◽  
...  

Since the last influenza pandemic in 2009, H1N1pdm has been introduced into the swine population in Europe where, in combination with swine influenza A virus (IAV) lineages, it started to generate a variety of reassortant viruses of unknown zoonotic risk for humans. To study these reassortment events, we isolated a wild swine lung cell clone (C22) susceptible to IAV infection. We established conditions for co-infection and passaging of H1N1pdm and swine avian-like H1N1. After 7 passages, we plaque-purified C22-adapted strains, characterized their genome composition by next-generation sequencing and analysed replication abilities in swine and human lung cell lines as well as in human lung tissue ex vivo. Among C22-adapted viruses isolated from co-infection, we revealed reassortants carrying PB1/PA/NA or only PB1/PA from H1N1pdm. We also detected exclusively swine H1N1-derived strains. All isolates carried distinct mutations. As expected, adapted viruses reached higher titers compared to both parental strains in swine lung cells. Furthermore, all C22-adapted viruses were able to replicate in human lung A549 cells without any prior adaptation to the human host. Strikingly, all reassortants were able to infect and efficiently replicate in human lung tissue ex vivo, indicating that these viruses might pose a zoonotic risk. To summarize, we successfully established an in vitro swine-like model to study reassortment and adaptation of IAVs currently circulating in swine. Our results indicate that our model might be a useful tool to prospectively evaluate the compatibility of different IAV strains to generate reassortants, which might represent a threat to the human population.


Allergy ◽  
1986 ◽  
Vol 41 (5) ◽  
pp. 319-326 ◽  
Author(s):  
H. Bergstrand ◽  
B. Lundquist ◽  
B.-Å. Petersson

2012 ◽  
Vol 80 (6) ◽  
pp. 1980-1986 ◽  
Author(s):  
Laura J. MacDonald ◽  
Richard C. Kurten ◽  
Daniel E. Voth

ABSTRACTCoxiella burnetiiis the bacterial agent of human Q fever, an acute, flu-like illness that can present as chronic endocarditis in immunocompromised individuals. Following aerosol-mediated transmission,C. burnetiireplicates in alveolar macrophages in a unique phagolysosome-like parasitophorous vacuole (PV) required for survival. The mechanisms ofC. burnetiiintracellular survival are poorly defined and a recent Q fever outbreak in the Netherlands emphasizes the need for better understanding this unique host-pathogen interaction. We recently demonstrated that inhibition of host cyclic AMP-dependent protein kinase (PKA) activity negatively impacts PV formation. In the current study, we confirmed PKA involvement in PV biogenesis and probed the role of PKA signaling duringC. burnetiiinfection of macrophages. Using PKA-specific inhibitors, we found the kinase was needed for biogenesis of prototypical PV andC. burnetiireplication. PKA and downstream targets were differentially phosphorylated throughout infection, suggesting prolonged regulation of the pathway. Importantly, the pathogen actively triggered PKA activation, which was also required for PV formation by virulentC. burnetiiisolates during infection of primary human alveolar macrophages. A subset of PKA-specific substrates were differentially phosphorylated duringC. burnetiiinfection, suggesting the pathogen uses PKA signaling to control distinct host cell responses. Collectively, the current results suggest a versatile role for PKA inC. burnetiiinfection and indicate virulent organisms usurp host kinase cascades for efficient intracellular growth.


2013 ◽  
Vol 82 (1) ◽  
pp. 275-285 ◽  
Author(s):  
Jens Jäger ◽  
Sebastian Marwitz ◽  
Jana Tiefenau ◽  
Janine Rasch ◽  
Olga Shevchuk ◽  
...  

ABSTRACTHistological and clinical investigations describe late stages of Legionnaires' disease but cannot characterize early events of human infection. Cellular or rodent infection models lack the complexity of tissue or have nonhuman backgrounds. Therefore, we developed and applied a novel model forLegionella pneumophilainfection comprising living human lung tissue. We stimulated lung explants withL. pneumophilastrains and outer membrane vesicles (OMVs) to analyze tissue damage, bacterial replication, and localization as well as the transcriptional response of infected tissue. Interestingly, we found that extracellular adhesion ofL. pneumophilato the entire alveolar lining precedes bacterial invasion and replication in recruited macrophages. In contrast, OMVs predominantly bound to alveolar macrophages. Specific damage to septa and epithelia increased over 48 h and was stronger in wild-type-infected and OMV-treated samples than in samples infected with the replication-deficient, type IVB secretion-deficient DotA−strain. Transcriptome analysis of lung tissue explants revealed a differential regulation of 2,499 genes after infection. The transcriptional response included the upregulation of uteroglobin and the downregulation of the macrophage receptor with collagenous structure (MARCO). Immunohistochemistry confirmed the downregulation of MARCO at sites of pathogen-induced tissue destruction. Neither host factor has ever been described in the context ofL. pneumophilainfections. This work demonstrates that the tissue explant model reproduces realistic features of Legionnaires' disease and reveals new functions for bacterial OMVs during infection. Our model allows us to characterize early steps of human infection which otherwise are not feasible for investigations.


2015 ◽  
Vol 83 (3) ◽  
pp. 1190-1198 ◽  
Author(s):  
Joseph G. Graham ◽  
Caylin G. Winchell ◽  
Uma M. Sharma ◽  
Daniel E. Voth

Coxiella burnetiicauses human Q fever, a zoonotic disease that presents with acute flu-like symptoms and can result in chronic life-threatening endocarditis. In human alveolar macrophages,C. burnetiiuses a Dot/Icm type IV secretion system (T4SS) to generate a phagolysosome-like parasitophorous vacuole (PV) in which to replicate. The T4SS translocates effector proteins, or substrates, into the host cytosol, where they mediate critical cellular events, including interaction with autophagosomes, PV formation, and prevention of apoptosis. Over 100C. burnetiiDot/Icm substrates have been identified, but the function of most remains undefined. Here, we identified a novel Dot/Icm substrate-encoding open reading frame (CbuD1884) present in allC. burnetiiisolates except the Nine Mile reference isolate, where the gene is disrupted by a frameshift mutation, resulting in a pseudogene. The CbuD1884 protein contains two transmembrane helices (TMHs) and a coiled-coil domain predicted to mediate protein-protein interactions. The C-terminal region of the protein contains a predicted Dot/Icm translocation signal and was secreted by the T4SS, while the N-terminal portion of the protein was not secreted. When ectopically expressed in eukaryotic cells, the TMH-containing N-terminal region of the CbuD1884 protein trafficked to the endoplasmic reticulum (ER), with the C terminus dispersed nonspecifically in the host cytoplasm. This new Dot/Icm substrate is now termed ElpA (ER-localizingproteinA). Full-length ElpA triggered substantial disruption of ER structure and host cell secretory transport. These results suggest that ElpA is a pathotype-specific T4SS effector that influences ER function duringC. burnetiiinfection.


2015 ◽  
Vol 6 (12) ◽  
pp. 6971-6979 ◽  
Author(s):  
Ahsan R. Akram ◽  
Nicolaos Avlonitis ◽  
Annamaria Lilienkampf ◽  
Ana M. Perez-Lopez ◽  
Neil McDonald ◽  
...  

A fluorescently labelled ubiquicidin peptide enables bacterial detection in human lung tissuein vitro.


Gene Therapy ◽  
2000 ◽  
Vol 7 (8) ◽  
pp. 675-678 ◽  
Author(s):  
S McBride ◽  
D Rannie ◽  
D J Harrison

1998 ◽  
Author(s):  
Zhiwei Huang ◽  
Chee T. Chia ◽  
Cheong Hoong Diong ◽  
Sing Lee ◽  
Wei-Ming Zheng ◽  
...  

2021 ◽  
Vol 11 (2) ◽  
pp. 360-369
Author(s):  
Caide Xie ◽  
Tianjing Zhao ◽  
Liang Fang

In order to explore the high-resolution CT findings of leukemia pulmonary infiltration and chemotherapy outcomes and the in vitro study of human lung tissue, this paper selected a total of 120 clinically or surgically confirmed leukemia patients at the designated hospital of the study from December 2014 to December 2018, and divided them into three groups according to the random number table method: pulmonary infiltration group, chemotherapy outcome group and in vitro study group, with 40 cases in each group. The CT imaging features of the three groups of patients were observed and summarized respectively; the anomalous evaluation indexes of pulmonary parenchyma tissue abnormalities included CT halo sign, air crescent sign, lung segment consolidation, bronchial vascular bundle and nodules; the CT abnormalities such as thickening of the interlobular septum, bronchial interstitial thickening, nodular shadow, ground glassy change, and air cavity consolidation were selected as observation indicators. The results show that all cases have multiple solid nodules or multiple plaques, varying in number, size and distribution, in which 13 cases have multiple patchy shadows, 9 cases have multiple knots and 11 cases have multiple plaques and nodules; lesions are mainly distributed along the bronchial vessels in 21 cases, and 9 cases are along the center of the small leaves and 5 cases are randomly distributed; there are 13 cases that have frosted glass, in which 4 cases with pleural effusion, 9 cases with mold infection, show multiple patchy shadows with halo signs and layered mold balls. In summary, leukemia pulmonary infiltration has polymorphic high-resolution CT findings and chemotherapy outcomes; high-resolution CT imaging and in vitro studies of human lung tissue have important clinical and pathological research value for leukemia infiltration and chemotherapy outcome. The results of this study provide a reference for the further researches on high-resolution CT findings of pulmonary infiltration and chemotherapy outcomes and in vitro studies of human lung tissue.


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