β-Casein(94-123)-derived peptides differently modulate production of mucins in intestinal goblet cells

2014 ◽  
Vol 82 (1) ◽  
pp. 36-46 ◽  
Author(s):  
Pascale Plaisancié ◽  
Rachel Boutrou ◽  
Monique Estienne ◽  
Gwénaële Henry ◽  
Julien Jardin ◽  
...  

We recently reported the identification of a peptide from yoghurts with promising potential for intestinal health: the sequence (94-123) of bovine β-casein. This peptide, composed of 30 amino acid residues, maintains intestinal homoeostasis through production of the secreted mucin MUC2 and of the transmembrane-associated mucin MUC4. Our study aimed to search for the minimal sequence responsible for the biological activity of β-CN(94-123) by using several strategies based on (i) known bioactive peptides encrypted in β-CN(94-123), (ii) in silico prediction of peptides reactivity and (iii) digestion of β-CN(94-123) by enzymes of intestinal brush border membranes. The revealed sequences were tested in vitro on human intestinal mucus-producing HT29-MTX cells. We demonstrated that β-CN(108-113) (an ACE-inhibitory peptide) and β-CN(114-119) (an opioid peptide named neocasomorphin-6) up-regulated MUC4 expression whereas levels of the secreted mucins MUC2 and MUC5AC remained unchanged. The digestion of β-CN(94-123) by intestinal enzymes showed that the peptides β-CN(94-108) and β-CN(117-123) were present throughout 1·5 to 3 h of digestion, respectively. These two peptides raised MUC5AC expression while β-CN(117-123) also induced a decrease in the level of MUC2 mRNA and protein. In addition, this inhibitory effect was reproduced in airway epithelial cells. In conclusion, β-CN(94-123) is a multifunctional molecule but only the sequence of 30 amino acids has a stimulating effect on the production of MUC2, a crucial factor of intestinal protection.

2020 ◽  
Vol 11 ◽  
Author(s):  
Mudit Agarwal ◽  
Piyush Ranjan ◽  
Upendra Baitha ◽  
Ankit Mittal

Hydroxychloroquine has gained much attention as one of the candidate drugs that can be repurposed as a prophylactic agent against SARS-CoV-2, the agent responsible for the COVID-19 pandemic. Due to high transmissibility and presence of asymptomatic carriers and presymptomatic transmission, there is need for a chemoprophylactic agent to protect the high-risk population. In this review, we dissect the currently available evidence on hydroxychloroquine prophylaxis from a clinical and pharmacological point of view. In vitro studies on Vero cells show that hydroxychloroquine effectively inhibits SARS-CoV-2 by affecting viral entry and viral transport via endolysosomes. However, this efficacy has failed to replicate in in vivo animal models as well as in most clinical observational studies and clinical trials assessing pre-exposure prophylaxis and postexposure prophylaxis in healthcare workers. An analysis of the pharmacology of HCQ in COVID-19 reveals certain possible reasons for this failure—a pharmacokinetic failure due to failure to achieve adequate drug concentration at the target site and attenuation of its inhibitory effect due to the presence of TMPRSS2 in airway epithelial cells. Currently, many clinical trials on HCQ prophylaxis in HCW are ongoing; these factors should be taken into account. Using higher doses of HCQ for prophylaxis is likely to be associated with increased safety concerns; thus, it may be worthwhile to focus on other possible interventions.


Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 509 ◽  
Author(s):  
Meenakshi Tiwary ◽  
Robert J. Rooney ◽  
Swantje Liedmann ◽  
Kim S. LeMessurier ◽  
Amali E. Samarasinghe

Eosinophils, previously considered terminally differentiated effector cells, have multifaceted functions in tissues. We previously found that allergic mice with eosinophil-rich inflammation were protected from severe influenza and discovered specialized antiviral effector functions for eosinophils including promoting cellular immunity during influenza. In this study, we hypothesized that eosinophil responses during the early phase of influenza contribute to host protection. Using in vitro and in vivo models, we found that eosinophils were rapidly and dynamically regulated upon influenza A virus (IAV) exposure to gain migratory capabilities to traffic to lymphoid organs after pulmonary infection. Eosinophils were capable of neutralizing virus upon contact and combinations of eosinophil granule proteins reduced virus infectivity through hemagglutinin inactivation. Bi-directional crosstalk between IAV-exposed epithelial cells and eosinophils occurred after IAV infection and cross-regulation promoted barrier responses to improve antiviral defenses in airway epithelial cells. Direct interactions between eosinophils and airway epithelial cells after IAV infection prevented virus-induced cytopathology in airway epithelial cells in vitro, and eosinophil recipient IAV-infected mice also maintained normal airway epithelial cell morphology. Our data suggest that eosinophils are important in the early phase of IAV infection providing immediate protection to the epithelial barrier until adaptive immune responses are deployed during influenza.


2018 ◽  
Vol 112 ◽  
pp. 163-168 ◽  
Author(s):  
Cynthia M. Schwartz ◽  
Braedyn A. Dorn ◽  
Selam Habtemariam ◽  
Cynthia L. Hill ◽  
Tendy Chiang ◽  
...  

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Rakesh K. Kumar ◽  
Jessica S. Siegle ◽  
Gerard E. Kaiko ◽  
Cristan Herbert ◽  
Joerg E. Mattes ◽  
...  

The pathogenesis of allergic asthma in childhood remains poorly understood. Environmental factors which appear to contribute to allergic sensitisation, with development of a Th2-biased immunological response in genetically predisposed individuals, include wheezing lower respiratory viral infections in early life and exposure to airborne environmental pollutants. These may activate pattern recognition receptors and/or cause oxidant injury to airway epithelial cells (AECs). In turn, this may promote Th2 polarisation via a “final common pathway” involving interaction between AEC, dendritic cells, and CD4+ T lymphocytes. Potentially important cytokines produced by AEC include thymic stromal lymphopoietin and interleukin-25. Their role is supported by in vitro studies using human AEC, as well as by experiments in animal models. To date, however, few investigations have employed models of the induction phase of childhood asthma. Further research may help to identify interventions that could reduce the risk of allergic asthma.


mBio ◽  
2013 ◽  
Vol 4 (2) ◽  
Author(s):  
Renee W. Y. Chan ◽  
Leo L. M. Poon

ABSTRACT A novel betacoronavirus, human coronavirus (HCoV-EMC), has recently been detected in humans with severe respiratory disease. Further characterization of HCoV-EMC suggests that this virus is different from severe acute respiratory syndrome coronavirus (SARS-CoV) because it is able to replicate in multiple mammalian cell lines and it does not use angiotensin-converting enzyme 2 as a receptor to achieve infection. Additional research is urgently needed to better understand the pathogenicity and tissue tropism of this virus in humans. In their recent study published in mBio, Kindler et al. shed some light on these important topics (E. Kindler, H. R. Jónsdóttir, M. Muth, O. J. Hamming, R. Hartmann, R. Rodriguez, R. Geffers, R. A. Fouchier, C. Drosten, M. A. Müller, R. Dijkman, and V. Thiel, mBio 4[1]:e00611-12, 2013). These authors report the use of differentiated pseudostratified human primary airway epithelial cells, an in vitro model with high physiological relevance to the human airway epithelium, to characterize the cellular tropism of HCoV-EMC. More importantly, the authors demonstrate the potential use of type I and type III interferons (IFNs) to control viral infection.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1281
Author(s):  
Shan Guan ◽  
Max Darmstädter ◽  
Chuanfei Xu ◽  
Joseph Rosenecker

In vitro-transcribed (IVT) mRNA has come into focus in recent years as a potential therapeutic approach for the treatment of genetic diseases. The nebulized formulations of IVT-mRNA-encoding alpha-1-antitrypsin (A1AT-mRNA) would be a highly acceptable and tolerable remedy for the protein replacement therapy for alpha-1-antitrypsin deficiency in the future. Here we show that lipoplexes containing A1AT-mRNA prepared in optimum conditions could successfully transfect human bronchial epithelial cells without significant toxicity. A reduction in transfection efficiency was observed for aerosolized lipoplexes that can be partially overcome by increasing the initial number of components. A1AT produced from cells transfected by nebulized A1AT-mRNA lipoplexes is functional and could successfully inhibit the enzyme activity of trypsin as well as elastase. Our data indicate that aerosolization of A1AT-mRNA therapy constitutes a potentially powerful means to transfect airway epithelial cells with the purpose of producing functional A1AT, while bringing along the unique advantages of IVT-mRNA.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ivy Aneas ◽  
Donna C. Decker ◽  
Chanie L. Howard ◽  
Débora R. Sobreira ◽  
Noboru J. Sakabe ◽  
...  

AbstractGenome-wide association studies (GWAS) have implicated the IL33 locus in asthma, but the underlying mechanisms remain unclear. Here, we identify a 5 kb region within the GWAS-defined segment that acts as an enhancer-blocking element in vivo and in vitro. Chromatin conformation capture showed that this 5 kb region loops to the IL33 promoter, potentially regulating its expression. We show that the asthma-associated single nucleotide polymorphism (SNP) rs1888909, located within the 5 kb region, is associated with IL33 gene expression in human airway epithelial cells and IL-33 protein expression in human plasma, potentially through differential binding of OCT-1 (POU2F1) to the asthma-risk allele. Our data demonstrate that asthma-associated variants at the IL33 locus mediate allele-specific regulatory activity and IL33 expression, providing a mechanism through which a regulatory SNP contributes to genetic risk of asthma.


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