Search bioRxiv⌕ Search

Biology subjects

Shields, M. D.

Publications and source records attributed to Shields, M. D..

5 recordsLinked to original sources

Age-dependent expression and antiviral activity of interferon epsilon in respiratory epithelium

Respiratory syncytial virus (RSV) disease burden is greatest between six weeks and 6 months of life, with young age the most common risk factor among hospitalised children. A robust innate immune response in the airway epithelium is crucial for mitigating RSV-associated disease, but early-life immune responses to infection remain largely unexplored. RNA-seq analysis of RSV-infected primary nasal epithelial cell cultures from healthy infants at birth and one year revealed diminished expression of interferon epsilon (IFNE), a poorly characterised type I IFN, in newborns versus one-year. We hypothesised, therefore, that IFNE plays an important role during infant RSV infection. We found that IFNE is endogenously expressed in airway epithelial cell lines. Recombinant human IFN{varepsilon} (rhIFN{varepsilon}) induced an antiviral state against an RSV clinical isolate and related Sendai virus, but not SARS-CoV-2 under the conditions tested. The antiviral potency of rhIFN{varepsilon} was diminished relative to rhIFN beta (rhIFN{beta}1) or rhIFN lambda-1 (rhIFN{lambda}1), as evidenced by IC50 data. Importantly, rhIFN{varepsilon} induced similar ISGs as rhIFN{beta}1 but demonstrated a transient temporal expression profile that differed from both rhIFN{beta}1 and rhIFN{lambda}1. These results suggest that lower IFN{varepsilon} expression at birth may contribute to increased susceptibility to severe RSV-associated disease, offering insights into potential therapeutic interventions.

microbiology↗

Inhibition of the TLR4 signalling pathway with TAK-242 reduces RSV infection and cytokine release in primary airway epithelial cells

Respiratory syncytial virus (RSV) infection is the leading cause of hospitalisation in children worldwide, but there is still no vaccine or anti-viral treatment available. RSV has been implicated in the development of respiratory diseases such as asthma. Toll like receptor 4 (TLR4) has been well characterised in the immune responses to RSV. However, the role of TLR4 in RSV infection remains unclear. To study RSV in the lung epithelium, where RSV preferentially infects ciliated cells, we used a well-differentiated primary airway epithelial cell (WD-PAEC) model: a pseudostratified epithelium that produces mucus and beating cilia. We demonstrate in this physiologically relevant model that TLR4 is a pro-viral factor. Inhibition of TLR4 using TAK-242 significantly reduces RSV titres in WD-PAECs in a dose-dependent manner but has no effect on RSV growth kinetics in a range of immortalised respiratory-derived cell lines. Specific inhibition of a range of downstream effectors of TLR4 signalling in the WD-PAEC model identified p38 MAPK as a pro-viral factor, whereas inhibition of MEK1/2 significantly increased RSV titres. Our data demonstrate a role for TLR4 in RSV infection and highlight the importance of biologically relevant models to study virus-host interactions. Author summaryRespiratory Syncytial Virus (RSV) can cause severe respiratory infection in young children and is responsible for approximately 200,000 deaths worldwide every year. Despite decades of research since the identification of this virus in the 1950s there is still no vaccine or treatment available. Advances in research have led to the development of cell cultures that are very similar to the cells that line human airways. These cultures provide an opportunity to study how viruses interacts with airway cells in a representative model and may provide insights that traditional research models have not yet been able to answer. Using this experimental model we show that a drug, TAK-242 which targets a pathogen recognition receptor on the surface of cells, reduces growth of RSV and dampens the immune response to infection in these airway cells. Our data demonstrate potential targets for RSV treatments and also highlight the importance of using relevant experimental models.

microbiology↗

Comparative therapeutic potential of ALX-0171 and palivizumab against RSV clinical isolate infection of well-differentiated primary pediatric bronchial epithelial cell cultures

Respiratory syncytial virus (RSV) causes severe lower respiratory tract infections in young infants. There are no RSV-specific treatments available. Ablynx has been developing an anti-RSV F-specific Nanobody(R), ALX-0171. To characterise the therapeutic potential of ALX-0171 we exploited our well-differentiated primary pediatric bronchial epithelial cell (WD-PBEC)/RSV infection model, which replicates several hallmarks of RSV disease in vivo. Using 2 clinical isolates (BT2a; Memphis 37), we compared the therapeutic potential of ALX-0171 with palivizumab, which is currently prescribed for RSV prophylaxis in high-risk infants. ALX-0171 treatment (900 mM) at 24 h post-infection reduced apically released RSV titers to near or below the limit of detection within 24 h for both strains. Progressively lower doses resulted in concomitantly diminished RSV neutralisation. ALX-0171 was approximately 3 fold more potent in this therapeutic RSV/WD-PBEC model than palivizumab (mean IC50 = 346.9-363.6 nM and 1048-1090 nM for ALX-0171 and palivizumab, respectively), irrespective of the clinical isolate. When viral genomic copies (GC) were measured by RT-qPCR, the therapeutic effect was considerably less and GCs were only moderately reduced (0.62 - 1.28 Log10 copies/mL) by ALX-0171 treatment at 300 and 900 nM. Similar findings were evident for palivizumab. Therefore, ALX-0171 was very potent at neutralising RSV released from apical surfaces but only had a limited impact on virus replication. The data indicate a clear disparity between viable virus neutralisation and GC viral load, the latter of which does not discriminate between viable and neutralised RSV. This study validates the RSV/WD-PBEC model for the pre-clinical evaluation of RSV antivirals.

microbiology↗

METABOLIC DIVERSITY IN HUMAN NON-SMALL CELL LUNG CANCER CELLS

Intermediary metabolism in cancer cells is regulated by diverse cell-autonomous processes including signal transduction and gene expression patterns arising from specific oncogenotypes and cell lineages. Although it is well established that metabolic reprogramming is a hallmark of cancer, we lack a full view of the diversity of metabolic programs in cancer cells and an unbiased assessment of the associations between metabolic pathway preferences and other cell-autonomous processes. Here we quantified over 100 metabolic features, mostly from 13C enrichment of molecules from central carbon metabolism, in over 80 non-small cell lung cancer (NSCLC) cell lines cultured under identical conditions. Because these cell lines were extensively annotated for oncogenotype, gene expression, protein expression and therapeutic sensitivity, the resulting database enables the user to uncover new relationships between metabolism and these orthogonal processes.

cancer biology↗

The Role of Toll-like receptor 4 in respiratory syncytial virus replication, interferon lambda 1 induction, and chemokine responses.

Respiratory syncytial virus (RSV) infection is the leading cause of severe lower respiratory tract infections (LRTI) in infants worldwide. The immune responses to RSV infection are implicated in RSV pathogenesis but RSV immunopathogenesis in humans remains poorly understood. We previously demonstrated that IFN-{lambda}1 is the principle interferon induced following RSV infection of infants and well-differentiated primary pediatric bronchial epithelial cells (WD-PBECs). Interestingly, RSV F interacts with the TLR4/CD14/MD2 complex to initiate secretion of pro-inflammatory cytokines, while TLR4 stimulation with house dust mite induces IFN-{lambda}1 production. However, the role of TLR4 in RSV infection and concomitant IFN-{lambda}1 induction remains unclear. Using our RSV/WD-PBEC infection model, we found that CLI-095 inhibition of TLR4 resulted in significantly reduced viral growth kinetics, and secretion of IFN-{lambda}1 and pro-inflammatory chemokines. To elucidate specific TLR4 signalling intermediates implicated in virus replication and innate immune responses we selected 4 inhibitors, including LY294002, U0126, SB203580 and JSH-23. SB203580, a p38 MAPK inhibitor, reduced both viral growth kinetics and IFN-{lambda}1 secretion, while JSH-23, an NF-{kappa}B inhibitor, reduced IFN-{lambda}1 secretion without affecting virus growth kinetics. Our data indicate that TLR4 plays a role in RSV entry and/or replication and IFN-{lambda}1 induction following RSV infection is mediated, in part, by TLR4 signalling through NF- {kappa}B and/or p38 MAPK. Therefore, targeting TLR4 or downstream effector proteins could present novel treatment strategies against RSV.\n\nImportanceThe role of TLR4 in RSV infection and IFN-{lambda}1 induction is controversial. Using our WD-PBEC model, which replicates many hallmarks of RSV infection in vivo, we demonstrated that the TLR4 pathway is involved in both RSV infection and/or replication and the concomitant induction of IFN-{lambda}1 and other pro-inflammatory cytokines. Increasing our understanding of the role of TLR4 in RSV immunopathogenesis may lead to the development of novel RSV therapeutics.

microbiology↗