scholarly journals The Hag Protein of Moraxella catarrhalis Strain O35E Is Associated with Adherence to Human Lung and Middle Ear Cells

2003 ◽  
Vol 71 (9) ◽  
pp. 4977-4984 ◽  
Author(s):  
Melissa M. Holm ◽  
Serena L. Vanlerberg ◽  
Darren D. Sledjeski ◽  
Eric R. Lafontaine
Keyword(s):  
Cell Lines ◽  
Middle Ear ◽  
Moraxella Catarrhalis ◽  
Human Lung ◽  
Primary Cultures ◽  
A549 Cells ◽  
Pcr Analysis ◽  
Nucleotide Sequence Data ◽  
Human Lung Cells ◽  
Conjunctival Cells

ABSTRACT Previous studies have demonstrated that the Moraxella catarrhalis surface antigen UspA1 is an adhesin for Chang human conjunctival cells. The present report demonstrates that lack of UspA1 expression does not affect the adherence of strain O35E to A549 human lung cells or primary cultures of human middle ear epithelial (HMEE) cells. These results imply that another molecule mediates the adherence of M. catarrhalis to these two cell lines. To identify this adhesin, strain O35E was mutagenized with a transposon and 1,000 mutants were screened in a microcolony formation assay using A549 cells. Nine independent isolates exhibited an 8- to 19-fold reduction in adherence and contained a transposon in the same locus. Nucleotide sequence data and PCR analysis indicated that the transposons were inserted in different locations in the gene encoding the surface protein Hag. Quantitative assays using one representative transposon mutant, O35E.TN2, showed considerably decreased binding to A549 as well as HMEE cells. However, this mutant adhered at wild-type levels to Chang conjunctival cells. These findings suggest that the M. catarrhalis Hag protein is an adhesin for cell lines derived from human lung and middle ear tissues.

scholarly journals The Moraxella catarrhalis Porin-Like Outer Membrane Protein CD Is an Adhesin for Human Lung Cells

2004 ◽  
Vol 72 (4) ◽  
pp. 1906-1913 ◽  
Author(s):  
Melissa M. Holm ◽  
Serena L. Vanlerberg ◽  
Ian M. Foley ◽  
Darren D. Sledjeski ◽  
Eric R. Lafontaine
Keyword(s):  
Membrane Protein ◽  
Outer Membrane ◽  
Gene Product ◽  
Outer Membrane Protein ◽  
Moraxella Catarrhalis ◽  
Human Lung ◽  
A549 Cells ◽  
Vaccine Antigen ◽  
Lung Cells ◽  
Human Lung Cells

ABSTRACT The outer membrane protein CD (OMPCD) of Moraxella catarrhalis is an outer membrane protein with several attributes of a potential vaccine antigen. We isolated four transposon mutants of strain O35E on the basis of their reduced binding to A549 human lung cells in microcolony formation assays, and we determined that they contain a transposon in ompCD. We also found that these transposon insertions had pleiotropic effects: mutants grew slower, became serum sensitive, bound ∼10-fold less to A549 cells, and appeared transparent when grown on solid medium. We confirmed that these various phenotypes could be attributed solely to disruption of ompCD by constructing the isogenic strain O35E.CD1. O35E-ompCD was cloned, and recombinant Escherichia coli bacteria expressing the gene product exhibited a 10-fold increase in adherence to A549 cells. This is the first report of M. catarrhalis ompCD mutants, and our findings demonstrate that this gene product is an adhesin for human lung cells.

scholarly journals Cytotoxic Effects of Flubendazole in Human Lung Cancer Cell Line A549

2020 ◽  
Vol 11 (4) ◽  
Author(s):  
Elham Hoveizi ◽  
Fatemeh Fakharzadeh Jahromi
Keyword(s):  
Lung Cancer ◽  
Cell Viability ◽  
Human Lung ◽  
A549 Cells ◽  
Beclin 1 ◽  
Human Lung Cancer ◽  
Pcr Analysis ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Acridine Orange Staining

Background: The development of effective anticancer drugs is a significant health issue. Previous studies showed that members of the benzimidazole family have anticancer effects on several cancers Objectives: The present study investigated the cytotoxic effect of flubendazole on A549 human lung cancer cells. Methods: The A549 cells were treated with flubendazole at 1, 2, 5, and 10 µM concentrations for three days. Cell viability was measured by the MTT assay and Acridine orange staining. Also, the expressions of P62 and Beclin -1 were analyzed by qRT-PCR analysis. Results: Cell viability of A549 cells, in a concentration-dependent manner, showed significant differences between the treatment and control groups, and the IC50 value was determined to be 2 µM. Also, flubendazole reduced the expression of P62 and increased the expression of Beclin 1 in treated cells. Conclusions: Flubendazole induces cell death in A549 cells in a dose and time-dependent manner and can offer new factors in lung cancer therapeutic strategies.

scholarly journals Moraxella catarrhalis Might Be More Common than Expected in Acute Otitis Media in Young Finnish Children

2016 ◽  
Vol 54 (9) ◽  
pp. 2373-2379 ◽  
Author(s):  
Saara Sillanpää ◽  
Sami Oikarinen ◽  
Markku Sipilä ◽  
Lenka Kramna ◽  
Markus Rautiainen ◽  
...  
Keyword(s):  
Otitis Media ◽  
Middle Ear ◽  
Moraxella Catarrhalis ◽  
Acute Otitis Media ◽  
Pcr Analysis ◽  
Considerable Proportion ◽  
Bacterial Dna ◽  
Content Type ◽  
Conventional Culture

According to studies based on bacterial cultures of middle ear fluids,Streptococcus pneumoniae,Haemophilus influenzae, andMoraxella catarrhalishave been the most common pathogens in acute otitis media. However, bacterial culture can be affected by reduced viability or suboptimal growth of bacteria. PCR detects bacterial DNA from samples with greater sensitivity than culture. In the present study, we analyzed the middle ear pathogens with both conventional culture and semiquantitative real-time PCR in 90 middle ear fluid samples obtained from children aged 5 to 42 months during acute otitis media episodes. Samples were tested for the presence ofS. pneumoniae,H. influenzae,M. catarrhalis,Alloiococcusotitidis,Staphylococcus aureus, andPseudomonas aeruginosa. One or more bacterial pathogens were detected in 42 (47%) samples with culture and in 69 (77%) samples with PCR. According to PCR analysis,M. catarrhalisresults were positive in 42 (47%) samples,H. influenzaein 30 (33%),S. pneumoniaein 27 (30%),A. otitidisin 6 (6.7%),S. aureusin 5 (5.6%), andP. aeruginosain 1 (1.1%). Multibacterial etiology was seen in 34 (38%) samples, andM. catarrhaliswas detected in most (85%) of those cases. Fifteen signals forM. catarrhaliswere strong, suggesting a highly probable etiological role of the pathogen. In conclusion, even thoughM. catarrhalisis often a part of mixed flora in acute otitis media, a considerable proportion of cases may be primarily attributable to this pathogen.

Fe- and Zn-induced inhibition of Cd uptake in human lung cell lines: Speciation studies with H441 and A549 cells

2011 ◽  
Vol 25 (8) ◽  
pp. 1701-1711 ◽  
Author(s):  
Marc Mantha ◽  
Loubna El Idrissi ◽  
Tatiana Leclerc-Beaulieu ◽  
Catherine Jumarie
Keyword(s):  
Cell Lines ◽  
Human Lung ◽  
A549 Cells ◽  
Cd Uptake

scholarly journals Hag Directly Mediates the Adherence of Moraxella catarrhalis to Human Middle Ear Cells

2005 ◽  
Vol 73 (8) ◽  
pp. 5127-5136 ◽  
Author(s):  
Brian Bullard ◽  
Serena L. Lipski ◽  
Eric R. Lafontaine
Keyword(s):  
Middle Ear ◽  
Moraxella Catarrhalis ◽  
Primary Cultures ◽  
Surface Protein ◽  
Cell Types ◽  
Negative Control ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
E Coli ◽  
Human Middle Ear

ABSTRACT Moraxella catarrhalis is a human pathogen that causes otitis media in young children and lung infections in patients with chronic obstructive pulmonary disease. In this study, the role of the surface protein Hag in the adherence of multiple M. catarrhalis strains was examined. The hag genes of four clinical isolates were disrupted with a spectinomycin resistance cassette, and the binding of isogenic mutants to primary cultures of human middle ear epithelial cells (HMEE), as well as A549 pneumocytes, was measured. These experiments revealed that the attachment of most mutants to both cell types was 10-fold less than that of their wild-type progenitors. To determine whether Hag directly mediates adherence to human cells, the hag genes from three M. catarrhalis isolates were cloned and expressed in a nonadherent Escherichia coli cloning strain. At least 17-fold more E. coli bacteria expressing Hag attached to HMEE cells than an adherence-negative control. Surprisingly, Hag expression did not increase the binding of recombinant E. coli to A549 monolayers. Our data demonstrate that the involvement of Hag in M. catarrhalis adherence to A549 and HMEE cells is conserved among isolates and that Hag directly mediates binding to HMEE cells.

scholarly journals Aptamer Profiling of A549 Cells Infected with Low-Pathogenicity and High-Pathogenicity Influenza Viruses

Viruses ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1028 ◽  
Author(s):  
Kevin M. Coombs ◽  
Philippe F. Simon ◽  
Nigel J. McLeish ◽  
Ali Zahedi-Amiri ◽  
Darwyn Kobasa
Keyword(s):  
Influenza A ◽  
Human Lung ◽  
A549 Cells ◽  
Influenza Viruses ◽  
Post Translational Modification ◽  
Emerging Pathogens ◽  
Influenza A Viruses ◽  
Human Lung Cells ◽  
Wide Range ◽  
High Pathogenicity

Influenza A viruses (IAVs) are important animal and human emerging and re-emerging pathogens that are responsible for yearly seasonal epidemics and sporadic pandemics. IAVs cause a wide range of clinical illnesses, from relatively mild infections by seasonal strains, to acute respiratory distress during infections with highly pathogenic avian IAVs (HPAI). For this study, we infected A549 human lung cells with lab prototype A/PR/8/34 (H1N1) (PR8), a seasonal H1N1 (RV733), the 2009 pandemic H1N1 (pdm09), or with two avian strains, an H5N1 HPAI strain or an H7N9 strain that has low pathogenicity in birds but high pathogenicity in humans. We used a newly-developed aptamer-based multiplexed technique (SOMAscan®) to examine >1300 human lung cell proteins affected by the different IAV strains, and identified more than 500 significantly dysregulated cellular proteins. Our analyses indicated that the avian strains induced more profound changes in the A549 global proteome compared to all tested low-pathogenicity H1N1 strains. The PR8 strain induced a general activation, primarily by upregulating many immune molecules, the seasonal RV733 and pdm09 strains had minimal effect upon assayed molecules, and the avian strains induced significant downregulation, primarily in antimicrobial response, cardiovascular and post-translational modification systems.

scholarly journals In Vitro Cytotoxicity of Nanoparticles: A Comparison between Particle Size and Cell Type

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Devashri Sahu ◽  
G. M. Kannan ◽  
Mukul Tailang ◽  
R. Vijayaraghavan
Keyword(s):  
Cell Lines ◽  
Human Lung ◽  
Lung Epithelial Cells ◽  
Differential Sensitivity ◽  
Human Monocytes ◽  
Toxic Response ◽  
Human Lung Cells ◽  
Micron Size ◽  
Nano Size

The reduction in size of Zinc oxide (ZnO) and Silicon dioxide (SiO2) particles from micron to nano scale offers unique physical characteristics on one hand while making them cytotoxic on other hand. The present study was aimed at comparing cytotoxic effects of ZnO and SiO2 nanoparticles with their micron size and secondary aim was to compare responses of these particles to two different cell types, namely, human lung epithelial cells (L-132) and human monocytes (THP-1). The L-132 and THP-1 cells were exposed to nano and micron size of ZnO and SiO2 particles with different concentrations (5–500 μg/mL) for 24 h, and cytotoxicity was analyzed by MTT assay, live-dead staining, and TC-50 was calculated. ZnO and SiO2 particles showed concentration-dependent cytotoxicity in both cell lines. In size-dependent study, ZnO particles exhibited nearly equal toxicity profile in L-132 cells while in THP-1 cells nano ZnO showed more toxicity than its micron size. The SiO2 particles showed more toxicity in their nano size than micron size in both cell lines. Human monocytes, THP-1 cells, were more sensitive towards the toxicity of both particles than human lung cells, L-132. The results highlight the difference of cytotoxicity between particle sizes and differential sensitivity of cells towards the particles of same composition. In conclusion, ZnO and SiO2 particles exhibited concentration-dependent toxicity, which was more in their nano size than micron counterpart. However, the toxic response varies depending on type of cell exposed due to differential sensitivity.

scholarly journals Quantitative Proteomic Analyses of Influenza Virus-Infected Cultured Human Lung Cells

2010 ◽  
Vol 84 (20) ◽  
pp. 10888-10906 ◽  
Author(s):  
Kevin M. Coombs ◽  
Alicia Berard ◽  
Wanhong Xu ◽  
Oleg Krokhin ◽  
Xiaobo Meng ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Protein Function ◽  
Human Lung ◽  
Isotope Labeling ◽  
Morphological Changes ◽  
A549 Cells ◽  
Host Cells ◽  
Human Influenza Virus ◽  
Human Lung Cells ◽  
Cell Immunity

ABSTRACT Because they are obligate intracellular parasites, all viruses are exclusively and intimately dependent upon host cells for replication. Viruses, in turn, induce profound changes within cells, including apoptosis, morphological changes, and activation of signaling pathways. Many of these alterations have been analyzed by gene arrays, which measure the cellular “transcriptome.” Until recently, it has not been possible to extend comparable types of studies to globally examine all the host cellular proteins, which are the actual effector molecules. We have used stable isotope labeling by amino acids in cell culture (SILAC), combined with high-throughput two-dimensional (2-D) high-performance liquid chromatography (HPLC)/mass spectrometry, to determine quantitative differences in host proteins after infection of human lung A549 cells with human influenza virus A/PR/8/34 (H1N1) for 24 h. Of the 4,689 identified and measured cytosolic protein pairs, 127 were significantly upregulated at >95% confidence, 153 were significantly downregulated at >95% confidence, and a total of 87 proteins were upregulated or downregulated more than 5-fold at >99% confidence. Gene ontology and pathway analyses indicated differentially regulated proteins and included those involved in host cell immunity and antigen presentation, cell adhesion, metabolism, protein function, signal transduction, and transcription pathways.

Microarray analysis of Streptococcus pneumoniae gene expression changes to human lung epithelial cells

2008 ◽  
Vol 54 (3) ◽  
pp. 189-200 ◽  
Author(s):  
Xin-Ming Song ◽  
Wayne Connor ◽  
Shakiba Jalal ◽  
Karsten Hokamp ◽  
Andrew A. Potter
Keyword(s):  
Gene Expression ◽  
Streptococcus Pneumoniae ◽  
Epithelial Cells ◽  
Human Lung ◽  
Cell Envelope ◽  
A549 Cells ◽  
Lung Epithelial Cells ◽  
Pcr Analysis ◽  
Lung Epithelial ◽  
Human Lung Epithelial Cells

Streptococcus pneumoniae infection starts from the respiratory tract where interaction with host epithelial cells occurs. To gain more insights on pneumococcal pathogenesis, an oligonucleotide (oligo)-based microarray was used to investigate gene expression changes of one serotype 3 encapsulated pathogenic S. pneumoniae strain 82 and one unencapsulated avirulent S. pneumoniae strain R6 upon exposure to human lung epithelial cells (A549) for 1 and 3 h, respectively. We observed that genes associated with many functional categories were differentially regulated in strain 82, such as genes in pathogenesis, cell envelope, transcription, translation, transport, metabolism, and unknown functions. In contrast, few genes were changed in strain R6 except for genes in ribonucleotide biosynthesis and unknown functions. Quantitative real-time PCR analysis confirmed the microarray results for most of the genes tested. To further characterize functions of the selected genes, knockout mutants were constructed in strain R6. We demonstrated that 2 genetic loci, SP_2170 (AdcB, zinc ABC transporter) and SP_0157 (hypothetical protein), were involved in adherence to A549 cells. These data suggest that divergent gene expression changes occur in S. pneumoniae pathogenic and avirulent strains during interaction with human lung epithelial cells. Some of those genes are involved in pneumococcal pathogenesis.

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