Physiologic Cold Shock Increases Adherence ofMoraxella catarrhalisto and Secretion of Interleukin 8 in Human Upper Respiratory Tract Epithelial Cells

The innate immune system is the host’s first line of immune defence against any invading pathogen. To establish an infection in a human host the influenza virus must replicate in epithelial cells of the upper respiratory tract. However, there are several innate immune mechanisms in place to stop the virus from reaching epithelial cells. In addition to limiting viral replication and dissemination, the innate immune system also activates the adaptive immune system leading to viral clearance, enabling the respiratory system to return to normal homeostasis. However, an overzealous innate immune system or adaptive immune response can be associated with immunopathology and aid secondary bacterial infections of the lower respiratory tract leading to pneumonia. In this review, we discuss the mechanisms utilised by the innate immune system to limit influenza virus replication and the damage caused by influenza viruses on the respiratory tissues and how these very same protective immune responses can cause immunopathology.

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The histone demethylase KDM6B fine-tunes the host response to Streptococcus pneumoniae

10.1101/757906 ◽

2019 ◽

Author(s):

Michael G. Connor ◽

Tiphaine Marie-Noelle Camarasa ◽

Emma Patey ◽

Orhan Rasid ◽

Laura Barrio ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Epithelial Cells ◽

Respiratory Tract ◽

Chromatin Remodeling ◽

Host Response ◽

Histone Demethylase ◽

Infection Model ◽

Dependent Manner ◽

Upper Respiratory Tract ◽

Upper Respiratory

AbstractStreptococcus pneumoniae is a natural colonizer of the human upper respiratory tract and an opportunistic pathogen. After colonization, bacteria either remain in the human upper respiratory tract, or may progress to cause pneumococcal disease. Although epithelial cells are among the first to encounter pneumococci, the cellular processes and contribution of epithelial cells to the host response are poorly understood. Here, we show a S. pneumoniae serotype 6B ST90 strain, which does not cause disease in a murine infection model, induces a unique NF-κB signature response distinct from an invasive disease causing isolate of serotype 4 (TIGR4). This signature is characterized by activation of p65 (RelA) and requires a histone demethylase, KDM6B. At the molecular level, we show that interaction of the 6B strain with epithelial cells leads to chromatin remodeling within the IL-11 promoter in a KDM6B dependent manner, where KDM6B specifically demethylates histone H3 lysine 27 di-methyl. Chromatin remodeling of the IL-11 locus facilitates p65 access to three NF-κB sites, which are otherwise inaccessible when stimulated by IL-1β or TIGR4. Finally, we demonstrate through chemical inhibition of KDM6B, with GSK-J4 inhibitor, and through exogenous addition of IL-11 that the host responses to 6B ST90 and TIGR4 strains can be interchanged both in vitro and in a murine model of infection in vivo. Our studies hereby reveal how a chromatin modifier governs cellular responses during infection.

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Infection of lymphoid tissues in the macaque upper respiratory tract contributes to the emergence of transmissible measles virus

Journal of General Virology ◽

10.1099/vir.0.054650-0 ◽

2013 ◽

Vol 94 (9) ◽

pp. 1933-1944 ◽

Cited By ~ 25

Author(s):

Martin Ludlow ◽

Rory D. de Vries ◽

Ken Lemon ◽

Stephen McQuaid ◽

Emma Millar ◽

...

Keyword(s):

Epithelial Cells ◽

Respiratory Tract ◽

Immune Cells ◽

Measles Virus ◽

Upper Respiratory Tract ◽

Free Virus ◽

Cell Debris ◽

Cell Layers ◽

Infected Cells ◽

Upper Respiratory

Measles virus (MV), a member of the family Paramyxoviridae, remains a major cause of morbidity and mortality in the developing world. MV is spread by aerosols but the mechanism(s) responsible for the high transmissibility of MV are largely unknown. We previously infected macaques with enhanced green fluorescent protein-expressing recombinant MV and euthanized them at a range of time points. In this study a comprehensive pathological analysis has been performed of tissues from the respiratory tract around the peak of virus replication. Isolation of virus from nose and throat swab samples showed that high levels of both cell-associated and cell-free virus were present in the upper respiratory tract. Analysis of tissue sections from lung and primary bronchus revealed localized infection of epithelial cells, concomitant infiltration of MV-infected immune cells into the epithelium and localized shedding of cells or cell debris into the lumen. While high numbers of MV-infected cells were present in the tongue, these were largely encapsulated by intact keratinocyte cell layers that likely limit virus transmission. In contrast, the integrity of tonsillar and adenoidal epithelia was disrupted with high numbers of MV-infected epithelial cells and infiltrating immune cells present throughout epithelial cell layers. Disruption was associated with large numbers of MV-infected cells or cell debris ‘spilling’ from epithelia into the respiratory tract. The coughing and sneezing response induced by disruption of the ciliated epithelium, leading to the expulsion of MV-infected cells, cell debris and cell-free virus, contributes to the highly infectious nature of MV.

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Dual and Triple Epithelial Coculture Model Systems with Donor-Derived Microbiota and THP-1 Macrophages To Mimic Host-Microbe Interactions in the Human Sinonasal Cavities

mSphere ◽

10.1128/msphere.00916-19 ◽

2020 ◽

Vol 5 (1) ◽

Cited By ~ 1

Author(s):

Charlotte De Rudder ◽

Marta Calatayud Arroyo ◽

Sarah Lebeer ◽

Tom Van de Wiele

Keyword(s):

Microbial Community ◽

Epithelial Cells ◽

Respiratory Tract ◽

Model Systems ◽

Upper Respiratory Tract ◽

Microbe Interactions ◽

Upper Respiratory ◽

Host Microbe Interactions ◽

Nasal Microbiota

ABSTRACT The epithelium of the human sinonasal cavities is colonized by a diverse microbial community, modulating epithelial development and immune priming and playing a role in respiratory disease. Here, we present a novel in vitro approach enabling a 3-day coculture of differentiated Calu-3 respiratory epithelial cells with a donor-derived bacterial community, a commensal species (Lactobacillus sakei), or a pathobiont (Staphylococcus aureus). We also assessed how the incorporation of macrophage-like cells could have a steering effect on both epithelial cells and the microbial community. Inoculation of donor-derived microbiota in our experimental setup did not pose cytotoxic stress on the epithelial cell layers, as demonstrated by unaltered cytokine and lactate dehydrogenase release compared to a sterile control. Epithelial integrity of the differentiated Calu-3 cells was maintained as well, with no differences in transepithelial electrical resistance observed between coculture with donor-derived microbiota and a sterile control. Transition of nasal microbiota from in vivo to in vitro conditions maintained phylogenetic richness, and yet a decrease in phylogenetic and phenotypic diversity was noted. Additional inclusion and coculture of THP-1-derived macrophages did not alter phylogenetic diversity, and yet donor-independent shifts toward higher Moraxella and Mycoplasma abundance were observed, while phenotypic diversity was also increased. Our results demonstrate that coculture of differentiated airway epithelial cells with a healthy donor-derived nasal community is a viable strategy to mimic host-microbe interactions in the human upper respiratory tract. Importantly, including an immune component allowed us to study host-microbe interactions in the upper respiratory tract more in depth. IMPORTANCE Despite the relevance of the resident microbiota in sinonasal health and disease and the need for cross talk between immune and epithelial cells in the upper respiratory tract, these parameters have not been combined in a single in vitro model system. We have developed a coculture system of differentiated respiratory epithelium and natural nasal microbiota and incorporated an immune component. As indicated by absence of cytotoxicity and stable cytokine profiles and epithelial integrity, nasal microbiota from human origin appeared to be well tolerated by host cells, while microbial community composition remained representative for that of the human (sino)nasal cavity. Importantly, the introduction of macrophage-like cells enabled us to obtain a differential readout from the epithelial cells dependent on the donor microbial background to which the cells were exposed. We conclude that both model systems offer the means to investigate host-microbe interactions in the upper respiratory tract in a more representative way.

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Innate immunity gene expression by epithelial cells of upper respiratory tract in children with adenoid hypertrophy

Auris Nasus Larynx ◽

10.1016/j.anl.2017.11.011 ◽

2018 ◽

Vol 45 (4) ◽

pp. 753-759 ◽

Cited By ~ 2

Author(s):

Lyudmila Viktorovna Gankovskaya ◽

Valentina Pavlovna Bykova ◽

Leila Seimurovna Namasova-Baranova ◽

Alexander Viktorovich Karaulov ◽

Irina Viktorovna Rahmanova ◽

...

Keyword(s):

Gene Expression ◽

Innate Immunity ◽

Epithelial Cells ◽

Respiratory Tract ◽

Adenoid Hypertrophy ◽

Upper Respiratory Tract ◽

Immunity Gene ◽

Innate Immunity Gene ◽

Upper Respiratory

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Measles Virus Infection of Epithelial Cells in the Macaque Upper Respiratory Tract Is Mediated by Subepithelial Immune Cells

Journal of Virology ◽

10.1128/jvi.03258-12 ◽

2013 ◽

Vol 87 (7) ◽

pp. 4033-4042 ◽

Cited By ~ 41

Author(s):

M. Ludlow ◽

K. Lemon ◽

R. D. de Vries ◽

S. McQuaid ◽

E. L. Millar ◽

...

Keyword(s):

Epithelial Cells ◽

Virus Infection ◽

Respiratory Tract ◽

Immune Cells ◽

Measles Virus ◽

Upper Respiratory Tract ◽

Upper Respiratory

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Nontypeable Haemophilus influenzae Responds to Virus-Infected Cells with a Significant Increase in Type IV Pilus Expression

mSphere ◽

10.1128/msphere.00384-20 ◽

2020 ◽

Vol 5 (3) ◽

Cited By ~ 2

Author(s):

Elaine M. Mokrzan ◽

Kolapo A. Dairo ◽

Laura A. Novotny ◽

Lauren O. Bakaletz

Keyword(s):

Epithelial Cells ◽

Virus Infection ◽

Respiratory Tract ◽

Haemophilus Influenzae ◽

Chronic Obstructive ◽

Upper Respiratory Tract ◽

Type Iv Pilus ◽

Content Type ◽

Type Iv ◽

Upper Respiratory

ABSTRACT Nontypeable Haemophilus influenzae (NTHI) colonizes the human nasopharynx, but when the host immune response is dysregulated by upper respiratory tract (URT) virus infection, NTHI can gain access to more distal airway sites and cause disease. The NTHI type IV pilus (T4P) facilitates adherence, benign colonization, and infection, and its majority subunit PilA is in clinical trials as a vaccinogen. To further validate the strategy of immunization with PilA against multiple NTHI-induced diseases, it is important to demonstrate T4P expression under microenvironmental conditions that predispose to NTHI infection of the airway. Because URT infection commonly facilitates NTHI-induced diseases, we examined the influence of ongoing virus infection of respiratory tract epithelial cells on NTHI T4P expression in vitro. Polarized primary human airway epithelial cells (HAEs) were sequentially inoculated with one of three common URT viruses, followed by NTHI. Use of a reporter construct revealed that NTHI upregulated pilA promoter activity when cultured with HAEs infected with adenovirus (AV), respiratory syncytial virus (RSV), or rhinovirus (RV) versus that in mock-infected HAEs. Consistent with these results, pilA expression and relative PilA/pilin abundance, as assessed by quantitative reverse transcription-PCR (qRT-PCR) and immunoblot, respectively, were also significantly increased when NTHI was cultured with virus-infected HAEs. Collectively, our data strongly suggest that under conditions of URT virus infection, PilA vaccinogen induction of T4P-directed antibodies is likely to be highly effective against multiple NTHI-induced diseases by interfering with T4P-mediated adherence. We hypothesize that this outcome could thereby limit or prevent the increased load of NTHI in the nasopharynx that characteristically precedes these coinfections. IMPORTANCE Nontypeable Haemophilus influenzae (NTHI) is the predominant bacterial causative agent of many chronic and recurrent diseases of the upper and lower respiratory tracts. NTHI-induced chronic rhinosinusitis, otitis media, and exacerbations of cystic fibrosis and chronic obstructive pulmonary disease often develop during or just after an upper respiratory tract viral infection. We have developed a vaccine candidate immunogen for NTHI-induced diseases that targets the majority subunit (PilA) of the type IV twitching pilus (T4P), which NTHI uses to adhere to respiratory tract epithelial cells and that also plays a role in disease. Here, we showed that NTHI cocultured with virus-infected respiratory tract epithelial cells express significantly more of the vaccine-targeted T4P than NTHI that encounters mock-infected (healthy) cells. These results strongly suggest that a vaccine strategy that targets the NTHI T4P will be effective under the most common predisposing condition: when the human host has a respiratory tract virus infection.

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Nontypeable Haemophilus influenzae Type IV Pilus Mediates Augmented Adherence to Rhinovirus-Infected Human Airway Epithelial Cells

Infection and Immunity ◽

10.1128/iai.00248-20 ◽

2020 ◽

Vol 88 (9) ◽

Cited By ~ 1

Author(s):

Stephen L. Toone ◽

Michelle Ratkiewicz ◽

Laura A. Novotny ◽

Binh L. Phong ◽

Lauren O. Bakaletz

Keyword(s):

Epithelial Cells ◽

Respiratory Tract ◽

Haemophilus Influenzae ◽

Host Cell ◽

Bacterial Load ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Upper Respiratory Tract ◽

Type Iv ◽

Upper Respiratory

ABSTRACT Human rhinovirus (hRV) is frequently detected in the upper respiratory tract, and symptomatic infection is associated with an increased nasopharyngeal bacterial load, with subsequent development of secondary bacterial diseases. Nontypeable Haemophilus influenzae (NTHI) is a commensal bacterial species of the human nasopharynx; however, in the context of prior or concurrent upper respiratory tract viral infection, this bacterium commonly causes multiple diseases throughout the upper and lower respiratory tracts. The present study was conducted to determine the mechanism(s) by which hRV infection promotes the development of NTHI-induced diseases. We showed that hRV infection of polarized primary human airway epithelial cells resulted in increased adherence of NTHI, due in part to augmented expression of CEACAM1 and ICAM1, host cell receptors to which NTHI binds via engagement of multiple adhesins. Antibody blockade of these host cell receptors significantly reduced NTHI adherence. With a specific focus on the NTHI type IV pilus (T4P), which we have previously shown binds to ICAM1, an essential adhesin and virulence determinant, we next showed that T4P-directed antibody blockade significantly reduced NTHI adherence to hRV-infected airway cells and, further, that expression of this adhesin was required for the enhanced adherence observed. Collectively, these data provide a mechanism by which “the common cold” promotes diseases due to NTHI, and they add further support for the use of PilA (the majority subunit of T4P) as a vaccine antigen, since antibodies directed against PilA are expected to limit the notably increased bacterial load associated with hRV coinfection and thereby to prevent secondary NTHI-induced diseases of the respiratory tract.

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