scholarly journals A Tractable Drosophila Cell System Enables Rapid Identification of Acinetobacter baumannii Host Factors

Author(s):  
Qing-Ming Qin ◽  
Jianwu Pei ◽  
Gabriel Gomez ◽  
Allison Rice-Ficht ◽  
Thomas A. Ficht ◽  
...  
Author(s):  
Qing-Ming Qin ◽  
Jianwu Pei ◽  
Gabriel Gomez ◽  
Allison Rice-Ficht ◽  
Thomas A. Ficht ◽  
...  

AbstractAcinetobacter baumannii is an important causative agent of nosocomial infections worldwide. The pathogen also readily acquires resistance to antibiotics, and pan-resistant strains have been reported. A. baumannii is widely regarded as an extracellular bacterial pathogen. However, accumulating evidence demonstrates that the pathogen can invade, survive or persist in infected mammalian cells. Unfortunately, the molecular mechanisms controlling these processes remain poorly understood. Here, we show that Drosophila S2 cells provide several attractive advantages as a model system for investigating the intracellular lifestyle of the pathogen, including susceptibility to bacterial intracellular replication and limited infection-induced host cell death. We also show that the Drosophila system can be used to rapidly identify host factors, including MAP kinase proteins, which confer susceptibility to intracellular parasitism. Finally, analysis of the Drosophila system suggested that host proteins that regulate organelle biogenesis and membrane trafficking contribute to regulating the intracellular lifestyle of the pathogen. Taken together, these findings establish a novel model system for elucidating interactions between A. baumannii and host cells, define new factors that regulate bacterial invasion or intracellular persistence, and identify subcellular compartments in host cells that interact with the pathogen.


Coronaviruses ◽  
2021 ◽  
Vol 02 ◽  
Author(s):  
Hari Om Singh ◽  
Kamini Jakhar ◽  
Vijay Nema ◽  
Asha Krishnaraj ◽  
Ranjana Choudhari

Background: Angiotensin converting enzyme 2 (ACE2) is the main cellular receptor for entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and acts as a proinflammatory mediator of Coronavirus disease (COVID-19). The clinical outcome of SARS-CoV-2 infection is influenced by proinflammatory mediators. The specific microRNAs (miRNAs) influence the ACE2 expression and are accountable for the increased circulatory proinflammatory mediator levels. Thus host factors play a crucial role in COVID-19 pathophysiology. The pathogenesis of COVID-19 disease is not well understood. Hence we comprehended the role of miRNAs, proinflammatory cytokines and ACE2 in COVID-19 pathophysiology. Methods: We utilized multiple databases, specifically, EMBASE, PubMed (Medline) and Google Scholar for our search. Discussion: SARS-CoV-2 genes could be target of host miRNAs. The miRNAs regulate the expression of ACE2 in various organs including kidney, heart, blood vessels, and lung. ACE2 acts as a proinflammatory mediator of SARS-CoV-2 associated disease. Proinflammatory cytokines (IL-6, IL-1β and TNF) have been associated with severe COVID-19 disease. Hence variation in expression of miRNAs would influence the regulation of COVID-19 pathophysiology. The clinical outcomes of COVID -19 are variable which could be linked with the difference in binding of host miRNA to target genes. Conclusion: Correlation of these genes with severe or critical stages of patients will provide biomarkers for severity of lung inflammation which would be useful in rapid identification of patients in need of hospital admission. Analysis of relationship between the miRNAs and ACE2 will be helpful in designing anti-miR therapy for ACE2-related SARS-CoV-2 infection.


2014 ◽  
Vol 63 (9) ◽  
pp. 1154-1159 ◽  
Author(s):  
Te-Li Chen ◽  
Yi-Tzu Lee ◽  
Shu-Chen Kuo ◽  
Su-Pen Yang ◽  
Chang-Phone Fung ◽  
...  

Acinetobacter baumannii, Acinetobacter nosocomialis and Acinetobacter pittii are clinically relevant members of the Acinetobacter calcoaceticus–A. baumannii (Acb) complex and important nosocomial pathogens. These three species are genetically closely related and phenotypically similar; however, they differ in their epidemiology, antibiotic resistance and pathogenicity. In this study, we investigated the use of a multiplex PCR-based assay designed to detect internal fragments of the 16S–23S rRNA intergenic region and the gyrB and recA genes. The assay was capable of differentiating A. baumannii, A. nosocomialis and A. pittii in a reliable manner. In 23 different reference strains and 89 clinical isolates of Acinetobacter species, the assay accurately identified clinically relevant Acb complex species except those ‘between 1 and 3’ or ‘close to 13TU’. None of the non-Acb complex species was misidentified. In an analysis of 1034 positive blood cultures, the assay had a sensitivity of 92.4 % and specificity of 98.2 % for Acb complex identification. Our results show that a single multiplex PCR assay can reliably differentiate clinically relevant Acb complex species. Thus, this method may be used to better understand the clinical differences between infections caused by these species.


2021 ◽  
Author(s):  
Joep Beumer ◽  
Maarten H Geurts ◽  
Mart M Lamers ◽  
Jens Puschhof ◽  
Jingshu Zhang ◽  
...  

Rapid identification of host genes essential for virus replication may expedite the generation of therapeutic interventions. Genetic screens are often performed in transformed cell lines that poorly represent viral target cells in vivo, leading to discoveries that may not be translated to the clinic. Intestinal organoids (IOs) are increasingly used to model human disease and are amenable to genetic engineering. To discern which host factors are reliable anti-coronavirus therapeutic targets, we generate mutant clonal IOs for 19 host genes previously implicated in coronavirus biology. We verify ACE2 and DPP4 as entry receptors for SARS-CoV/SARS-CoV-2 and MERS-CoV respectively. SARS-CoV-2 replication in IOs does not require the endosomal Cathepsin B/L proteases, but specifically depends on the cell surface protease TMPRSS2. Other TMPRSS family members were not essential. The newly emerging coronavirus variant B.1.1.7, as well as SARS-CoV and MERS-CoV similarly depended on TMPRSS2. These findings underscore the relevance of non-transformed human models for coronavirus research, identify TMPRSS2 as an attractive pan-coronavirus therapeutic target, and demonstrate that an organoid knockout biobank is a valuable tool to investigate the biology of current and future emerging coronaviruses.


Author(s):  
A. M. Courgeon ◽  
M. Ropp ◽  
E. Rollet ◽  
J. Becker ◽  
C. Maisonhaute ◽  
...  

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Joep Beumer ◽  
Maarten H. Geurts ◽  
Mart M. Lamers ◽  
Jens Puschhof ◽  
Jingshu Zhang ◽  
...  

AbstractRapid identification of host genes essential for virus replication may expedite the generation of therapeutic interventions. Genetic screens are often performed in transformed cell lines that poorly represent viral target cells in vivo, leading to discoveries that may not be translated to the clinic. Intestinal organoids are increasingly used to model human disease and are amenable to genetic engineering. To discern which host factors are reliable anti-coronavirus therapeutic targets, we generate mutant clonal IOs for 19 host genes previously implicated in coronavirus biology. We verify ACE2 and DPP4 as entry receptors for SARS-CoV/SARS-CoV-2 and MERS-CoV respectively. SARS-CoV-2 replication in IOs does not require the endosomal Cathepsin B/L proteases, but specifically depends on the cell surface protease TMPRSS2. Other TMPRSS family members were not essential. The newly emerging coronavirus variant B.1.1.7, as well as SARS-CoV and MERS-CoV similarly depended on TMPRSS2. These findings underscore the relevance of non-transformed human models for coronavirus research, identify TMPRSS2 as an attractive pan-coronavirus therapeutic target, and demonstrate that an organoid knockout biobank is a valuable tool to investigate the biology of current and future emerging coronaviruses.


2020 ◽  
Vol Volume 13 ◽  
pp. 4125-4132
Author(s):  
Qiuyang Deng ◽  
Jinyong Zhang ◽  
Min Zhang ◽  
Zhou Liu ◽  
Yuxin Zhong ◽  
...  

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